ACQ fluorescent probe composition, cmc measurement method, stain cleaning concentration determination method, detergent delivery control method, and detergent delivery control system

Abstract

The present invention provides an ACQ fluorescent probe composition, which is characterized in that the ACQ fluorescent probe composition is a probe solution for directly determining the cmc concentration of a surfactant, the ACQ fluorescent probe composition comprises a probe molecule and an auxiliary agent, the probe molecule is a fluorescent molecule having the property of aggregation-caused luminescence quenching (ACQ), the auxiliary agent comprises more than one non-volatile organic solvent, and the auxiliary agent is a non-volatile organic solvent. The boiling point of the organic solvent is 100 DEG C or more, and the HSP distance Ra, which is the distance between the Hansen solubility parameters of the probe molecule and the organic solvent, is 17 (MPa) 1 / 2 or less. Also provided are a cmc measurement method, a stain cleaning concentration determination method, a detergent delivery control method, and a detergent delivery control system using the ACQ fluorescent probe composition.

Description

Technical Field

[0001] The present invention relates to an ACQ fluorescent probe composition, a cmc measuring method using the ACQ fluorescent probe composition, a stain cleaning concentration determination method, and a detergent dosing control method and system. Background Art

[0002] Detergents are usually composed of surfactants, builders and additives. Current automatic washing equipment mainly relies on the weight of the fabric load to add detergent, but the amount of detergent added by different washing machine brands varies significantly, and the universality and flexibility for different detergents and washing scenarios are poor.

[0003] The inventors have found through research that when the concentration of the surfactant in the washing water reaches the critical micelle concentration (cmc), the washing effect reaches the best cost-effective balance point. Therefore, they hope to monitor whether the concentration of the surfactant in the washing water reaches cmc as a basis for automatically adding detergent.

[0004] In addition, different detergent concentrations are required to clean clothes with different stains, and the concentrations may be greater than or equal to the critical micelle concentration cmc mentioned above. Therefore, different threshold concentrations can be determined for the three types of stains, namely oil stains, color stains and invisible stains. When the detergent concentration in the washing water is detected to have reached or exceeded the threshold concentration, it can be expected that the stains can be washed clean. Therefore, it is also hoped that the concentration of the surfactant in the washing water can be monitored to determine whether it has reached the threshold concentration as a basis for automatically adding detergent.

[0005] That is, the judgment basis for automatic detergent dispensing control can include the following two methods: using cmc as the judgment basis for the highest cost-effectiveness point, at which the cleaning efficiency is the highest; using the stain cleaning threshold concentration as the judgment basis for the degree of stain cleaning, at which the cleaning effect is the best. Usually, the stain cleaning threshold concentration ≥ cmc.

[0006] Conventional methods for detecting the cmc of surfactants include surface tension method, conductivity method and fluorescent probe method, etc., but the surface tension method requires a series of complex operations; the conductivity method cannot detect nonionic surfactants and surfactants with low conductivity; the fluorescent probe method has the problem that the sensitivity and accuracy of the probe are not high. For example, pyrene is usually used as a probe in the fluorescent probe method, and the cmc is determined by measuring the fluorescence peak intensity and ratio of the first and third emission peaks (373nm and 384nm) of pyrene. However, when the pyrene probe is used for online testing of cmc, there may be a peak position drift that causes the selected 373nm and 384nm to be not at the peak inflection point, thereby the problem of insufficient detection sensitivity, and it is necessary to find a more suitable probe molecule for fluorescent properties. In addition, the current fluorescence spectrophotometer also has the problem that the instrument equipment is difficult to miniaturize and the cost is high.

[0007] Fluorescent probe molecules are roughly divided into AIE molecules that adopt the aggregation-induced emission (AIE) strategy and ACQ molecules that adopt the aggregation-induced luminescence quenching (ACQ) strategy. We have previously successfully developed an AIE fluorescent probe composition comprising AIE molecules and auxiliary agents (patent document 1). However, compared with AIE molecules, the types and sources of ACQ molecules are more extensive. Most ACQ molecules already have efficient preparation methods and commercially available products. At the same time, compared with AIE molecules, ACQ molecules have lower probe costs and higher application cost performance while ensuring similar detection accuracy. Therefore, it is expected to develop a low-cost and easy-to-use ACQ fluorescent probe composition that can be used to monitor various scenarios such as the cmc of washing water, and has huge application prospects.

[0008] The current problem is that most of the ACQ probe molecules used to measure cmc are poorly water-soluble substances. In order to dissolve these hydrophobic substances, they are usually dissolved in organic solvents, such as tetrahydrofuran, ethanol, etc., and it is generally believed in the art that the presence of these organic solvents will cause deviations in the measurement results of cmc. Therefore, in order to avoid such problems, it is necessary to control the amount of organic solvent to a very small amount (non-patent document 1), or evaporate the volatile organic solvent before measurement or wait for it to evaporate naturally and remove it (non-patent documents 2, 3). Since these organic solvents are easy to volatilize, therefore, in actual application environments, ACQ probe solutions are not easy to store and keep for a long time, or need to be processed in advance before use, resulting in cumbersome operation of the cmc measurement process, reduced accuracy of measurement sampling, and lack of ease of use.

[0009] Prior art literature

[0010] Patent Literature

[0011] Patent document 1: CN116554861A

[0012] Non-patent literature

[0013] Non-patent document 1: "Role of Curcumin on The Determination of The CriticalMicellar Concentration by Absorbance, Fluorescence and Fluorescence AnisotropyTechniques, J Photochem. Photobiol., B, 2012, 115(3), 9-15

[0014] Non-patent literature 2: Determination of CTAB critical micelle concentration by pyrene fluorescence probe spectroscopy, Petrochemical Technology and Application, 2007, 25(1), 48-50

[0015] Non-patent document 3: Fluorescence Emission of Pyrene in Surfactant Solution, Advance in Colloid and Interface Science, 215 (2015), 1-12 Summary of the invention

[0016] Problems to be solved by the invention

[0017] The present invention is made in view of the above situation, and its purpose is to provide an ACQ fluorescent probe composition that is inexpensive and easy to use, which can be stored for a long time in the form of a stable solution and can be directly used to measure the cmc concentration of a surfactant solution. The present invention also provides a cmc measurement method for a surfactant solution based on the ACQ fluorescent probe composition, a stain cleaning concentration determination method, and a detergent dosing control method.

[0018] Methods used to solve problems

[0019] The inventors have conducted in-depth research on the above-mentioned problems and found that by adopting a specific combination of ACQ probe molecules and auxiliary agents, not only can the ACQ molecules be well dissolved in the auxiliary agent to form a stable probe solution that can be stored for a long time and directly used to measure the cmc of the surfactant solution; but also, the influence of the presence of the auxiliary agent on the cmc measurement result is controlled within an allowable range, and accurate measurement results can be obtained, thereby well solving the above-mentioned problems.

[0020] The present invention provides an ACQ fluorescent probe composition, which is characterized by being a probe solution for directly measuring the cmc concentration of a surfactant, comprising a probe molecule and an auxiliary agent, wherein the probe molecule is a fluorescent molecule having an aggregation-induced luminescence quenching (ACQ) property, and the auxiliary agent comprises one or more non-volatile organic solvents, wherein the boiling point of the organic solvent is above 100° C., and the distance between the probe molecule and the organic solvent, i.e., the HSP distance Ra, is within 17 (MPa). 1 / 2 the following.

[0021] Preferably, the Hansen solubility parameter (HSP) of the probe molecule is 15 (MPa) 1 / 2 ~35(MPa) 1 / 2 .

[0022] Preferably, the solubility of the probe molecule in the auxiliary agent is classified as soluble or above.

[0023] Preferably, the difference Δδ between the Hansen solubility parameters of the auxiliary agent and the probe molecule is -3 (MPa) 1 / 2 ~+12(MPa) 1 / 2 .

[0024] Preferably, the viscosity of the auxiliary agent is less than 30 mPa·s.

[0025] Preferably, the additive is soluble in water and has a density of 0.9 g / cm 3 ~1.2g / cm 3 .

[0026] Preferably, the flash point of the auxiliary agent is above 60°C.

[0027] Preferably, the probe molecule is an ACQ molecule whose luminescence strategy is based on changes in fluorescence intensity or characteristic wavelength, including ACQ molecules with blue-shift characteristics of characteristic wavelengths, ACQ molecules with red-shift characteristics of characteristic wavelengths, and ACQ molecules with unchanged characteristic wavelengths.

[0028] Preferably, the probe molecule is one or more ACQ molecules selected from curcumin (CUR), Nile red (NR), coumarin (C480), rhodamine B (RhB), N-phenyl-1-naphthylamine (NPN) and pyrene (PYR).

[0029] Preferably, the auxiliary agent contains one or more organic solvents selected from n-butanol, ethylene glycol, N-methylpyrrolidone (NMP), N-ethylpyrrolidone (NEP), dimethylformamide (DMF), diethylene glycol monoethyl ether (DGME), ethyl glycolate, polyethylene glycol 200 (PEG200), 1,3-butanediol and 1,5-pentanediol.

[0030] Preferably, the probe molecule is at least one ACQ molecule selected from curcumin (CUR), Nile red (NR) and coumarin (C480), and the auxiliary agent contains at least one organic solvent selected from N-methylpyrrolidone (NMP), N-ethylpyrrolidone (NEP), polyethylene glycol 200 (PEG200) and diethylene glycol monoethyl ether (DGME).

[0031] The present invention also provides a method for measuring the cmc of a surfactant solution, which is characterized by comprising the following steps in sequence:

[0032] Preparation steps: Prepare a series of surfactant solutions at different concentrations.

[0033] Probe adding step: adding a certain amount of probe solution to the surfactant solution,

[0034] Detection steps: Use the detection mechanism to detect the fluorescence response value of each surfactant solution, and

[0035] Determining step: drawing a fluorescence response value-concentration curve according to the result obtained in the detection step, wherein the fluorescence response value-concentration curve has at least a first platform area and a rising area, and determining the concentration corresponding to the inflection point where the fluorescence response value changes from the first platform area to the rising area as the cmc of the surfactant solution,

[0036] Wherein, the probe solution is the ACQ fluorescent probe composition of the present invention.

[0037] Preferably, in the determination step, the concentration corresponding to the intersection of the fitting straight line of the first platform area and the fitting straight line of the rising area in the fluorescence response value-concentration curve diagram is determined as the cmc of the surfactant solution.

[0038] Preferably, relative to 10 ml of the surfactant solution, the amount of solvent added to the probe solution does not exceed 400 μl, and the probe working concentration of the probe molecule does not exceed 10 ug / ml.

[0039] Preferably, the surfactant comprises at least one of anionic surfactants, nonionic surfactants and amphoteric surfactants.

[0040] Preferably, the surfactant solution further comprises a fluorescent whitening agent.

[0041] The present invention also provides a method for determining the stain cleaning concentration, which is characterized by comprising the following steps:

[0042] Liquid preparation step: adding a first predetermined amount of detergent into a washing device containing a predetermined amount of water and clothes, stirring and mixing to obtain washing water,

[0043] Sampling step: sampling from the washing water and adding a small amount of probe solution to obtain the washing water to be tested.

[0044] Detection step: using a detection mechanism to detect the fluorescence response value S of the washing water to be tested,

[0045] Determination step: judging whether the detergent concentration of the washing water to be tested is a stain cleaning concentration according to whether the detected fluorescence response value S reaches or exceeds a preset cleaning response threshold value S0; if it does not reach the preset cleaning response threshold value S0, the determination result is "no"; if it reaches or exceeds the preset cleaning response threshold value S0, the determination result is "yes", and

[0046] A control step: based on the determination result of the determination step, controlling the subsequent addition of the detergent in the liquid preparation step, wherein if the determination result is "no", returning to the liquid preparation step to continue adding a second predetermined amount of detergent, and then performing subsequent sampling steps, detection steps and determination steps; if the determination result is "yes", stopping adding the detergent, outputting the determination result,

[0047] Wherein, the probe solution is the ACQ fluorescent probe composition of the present invention.

[0048] Preferably, the cleaning response threshold S0 is a fluorescence response value corresponding to the critical micelle concentration cmc of the washing water, or a fluorescence response value corresponding to the stain cleaning threshold concentration Ct.

[0049] The stain removal threshold concentration Ct is the minimum concentration required to clean clothes with different stains, and is determined by the following formula 3:

[0050] Ct=cmc×(1+a) (Formula 3)

[0051] In Formula 3, cmc is the critical micelle concentration of the washing water, and a is the cleaning coefficient, which ranges from 0≤a≤10. Depending on the type and degree of dirtiness of the stains, a may take different values.

[0052] Preferably, the cleaning response threshold S0 is determined by the following formula 4 or formula 5:

[0053] S0=β×S max (Formula 4)

[0054] S0=S blank +β×(S max -S blank ) (Formula 5)

[0055] In the formula, S max is the maximum fluorescence intensity or the maximum voltage response value of the washing water, or the second platform value in the fluorescence response value-concentration curve of the washing water; S blank is the background fluorescence intensity or minimum voltage response value of the washing water, or the first platform value in the fluorescence response value-concentration curve of the washing water; β is the threshold percentage, the unit is 100%, and the range is 0<β<1. Corresponding to different types and degrees of dirtiness of stains, β can take different values.

[0056] The present invention also provides a detergent dispensing control method, which is characterized by comprising the following steps:

[0057] Liquid preparation step: in the washing device, a first predetermined amount of the detergent is added into the inner barrel according to the weight of the laundry and the amount of water inlet, and mixed with the water in the inner barrel to obtain washing water or detergent solution;

[0058] Sampling step: collecting a predetermined amount of the washing water or detergent solution from the inner barrel as a sample;

[0059] Liquid collection step: Take out a small amount of probe solution and add it to the sample.

[0060] Mixing step: mixing the sample and the probe solution to obtain a test solution;

[0061] Detection step: detecting the fluorescence response value of the test liquid and outputting a detection signal S;

[0062] Determination step: receiving the detection signal S, and determining whether the detergent concentration of the test liquid reaches the critical micelle concentration cmc or the preset cleaning threshold concentration Ct according to whether the detection signal S reaches or exceeds the preset response threshold S0, wherein the cleaning threshold concentration Ct is greater than or equal to the critical micelle concentration cmc; and

[0063] Controlling step: Based on the judgment result of the judging step, controlling the subsequent addition of the detergent, wherein if the judgment result is that the critical micelle concentration or the preset cleaning threshold concentration has not been reached, returning to the liquid preparation step to continue adding a second predetermined amount of the detergent into the inner barrel; if the judgment result is that the critical micelle concentration or the preset cleaning threshold concentration has been reached, stopping adding the detergent,

[0064] Wherein, the probe solution is the ACQ fluorescent probe composition of the present invention.

[0065] Preferably, the control step also includes a number limiting step: presetting a number threshold representing the maximum number of times the detergent is added. If, after the detergent has been added more than once, although the judgment result of the judgment step is still that the critical micelle concentration or the preset cleaning threshold concentration has not been reached, the number of times the detergent has been added has reached the number threshold, then stop adding the detergent in the liquid preparation step.

[0066] The present invention also provides a detergent dispensing control system, which is used to automatically control the amount of detergent dispensed in a washing device, wherein the washing device comprises: an inner barrel for placing laundry and water to be washed; a storage device for storing detergent; and a dispensing device for dispensing a first predetermined amount of the detergent into the inner barrel, mixing and stirring with the water in the inner barrel to obtain washing water or a detergent solution, characterized in that:

[0067] The detergent delivery control system comprises:

[0068] A liquid storage device, used for storing a probe solution;

[0069] a sampling device for collecting a predetermined amount of the washing water or detergent solution from the inner tub as a sample;

[0070] A liquid taking device, used for taking out a small amount of probe solution from the liquid storage device and adding it to the sample;

[0071] Mixing device: used for mixing the sample and the probe solution to obtain a test solution;

[0072] A detection device, used to detect the fluorescence response value of the test liquid and output a detection signal S;

[0073] A judging device: used for receiving the detection signal S, and judging whether the detergent concentration of the test liquid reaches the critical micelle concentration cmc or the preset cleaning threshold concentration Ct according to whether the detection signal S reaches or exceeds the preset response threshold S0, wherein the cleaning threshold concentration Ct is greater than or equal to the critical micelle concentration cmc;

[0074] a CMC determination device, for, under the condition that there is no laundry in the inner barrel, using the dispensing device to dispense a predetermined amount of the detergent into the inner barrel in batches, and using the liquid storage device, the sampling device, the liquid taking device, the mixing device and the detection device to repeatedly perform multiple groups of measurements, and determining the critical micelle concentration of the detergent solution according to a plurality of detection data corresponding to different detergent concentrations output by the detection device; and

[0075] a control device, for controlling the subsequent delivery of the detergent by the delivery device of the washing device based on the determination result of the determination device,

[0076] Wherein, if the judgment result of the judgment device is that the critical micelle concentration cmc or the preset cleaning threshold concentration Ct has not been reached, the control device controls the dispensing device to continue to dispense the second predetermined amount of the detergent into the inner barrel of the washing device; if the judgment result of the judgment device is that the critical micelle concentration cmc or the preset cleaning threshold concentration Ct has been reached or exceeded, the control device controls the dispensing device to stop dispensing the detergent;

[0077] Wherein, the probe solution is the ACQ fluorescent probe composition of the present invention.

[0078] Preferably, the cleaning response threshold S0 is a fluorescence response value corresponding to the critical micelle concentration cmc of the detergent solution, or a fluorescence response value corresponding to the stain cleaning threshold concentration Ct.

[0079] The critical micelle concentration cmc is a pre-determined critical micelle concentration of a detergent solution, or a critical micelle concentration of a detergent solution or washing water determined online by the cmc determination device.

[0080] The cleaning threshold concentration Ct is calculated using the following formula 3:

[0081] Ct=cmc×(1+a) (Formula 3)

[0082] Where a is the cleaning coefficient, ranging from 0≤a≤10. Depending on the type and degree of dirtiness of the stains, a can take different values.

[0083] Alternatively, the cleaning response threshold S0 is determined by the following formula 4 or formula 5:

[0084] S0=β×S max (Formula 4)

[0085] S0=S blank +β×(S max -S blank ) (Formula 5)

[0086] In the formula, S max is the maximum fluorescence intensity or the maximum voltage response value of the washing water, or the second platform value in the fluorescence response value-concentration curve of the washing water; S blank is the background fluorescence intensity or minimum voltage response value of the washing water, or the first platform value in the fluorescence response value-concentration curve of the washing water; β is the threshold percentage, the unit is 100%, and the range is 0<β<1. Corresponding to different types and degrees of dirtiness of stains, β can take different values.

[0087] Preferably, a number threshold indicating the maximum number of times the detergent is dispensed is also set in the control device. After the dispensing device has dispensed the detergent more than once, if the judgment result of the judgment device is still that the critical micelle concentration or the preset cleaning threshold concentration has not been reached, but the number of times the detergent has been dispensed has reached the number threshold, then the control device controls the dispensing device to stop dispensing the detergent.

[0088] Effects of the Invention

[0089] The ACQ fluorescent probe composition of the present invention adopts a specific combination of ACQ probe molecules and auxiliary agents, and the ACQ molecules can be dissolved in the auxiliary agents to form a stable probe solution, which can be stored for a long time and has good operability during measurement; and the cmc can be accurately detected within a suitable concentration range, thereby providing a cheap and easy-to-use ACQ fluorescent probe composition, which can be expected to be used in a wide range of fields including the washing industry, the detergent industry and the washing machine industry.

[0090] By using the above-mentioned ACQ fluorescent probe composition, a more convenient and accurate cmc measurement method, a stain cleaning concentration determination method for online judging whether clothes with different stains can be washed, and a detergent dispensing control method and a detergent dispensing control system for automatically controlling the amount of detergent in a washing device based on cost-effectiveness or cleaning effect can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0091] Figure 1 The fluorescence spectrum of the ACQ fluorescent probe composition (CUR-DGME) in Example 1 of the present invention measured in different concentrations of Supreme Biotech (Bright White) detergent solution (abbreviated as ZZLB) using a fluorescence spectrophotometer.

[0092] Figure 2 It is a fluorescence response value-detergent concentration curve graph showing the ACQ fluorescent probe composition (CUR-DGME) in Example 1 of the present invention, which selects the peak height data of the fluorescence intensity at the maximum emission wavelength Em=495nm as the fluorescence response value, and uses the fitting straight line intersection method to determine the cmc value or cmc range.

[0093] Figure 3 The ACQ fluorescent probe composition (NR-NMP) in Example 2 of the present invention is in different concentrations of Supreme Biotechnology (Bright White) washing water, and the voltage value obtained by using a fluorescent photodetector (CD detector) is used as the fluorescence response value to draw a fluorescence response value-detergent concentration curve, and the inflection point method is used to determine the cmc value or cmc range.

[0094] Figure 43 is a graph showing the fluorescence response value-detergent concentration curve obtained when the cmc of Supreme Biotech (Bright White) detergent solution (abbreviated as ZZLB) was measured using various ACQ fluorescent probe compositions in Example 3 of the present invention, (A) CUR probe composition, the auxiliary agents are BUT, EG, NMP, and PEG200 (labeled as PEG in the figure); (B) NR probe composition, the auxiliary agents are BUT, NMP and PEG200.

[0095] Figure 5 It is a graph showing the cmc of detergent solutions of various brands measured by the surface tension method in Example 4 of the present invention.

[0096] Figure 6 2 is a graph showing the fluorescence response value-detergent concentration curve when the two ACQ fluorescent probe compositions of the present invention are used to measure the cmc of detergent solutions of various brands in Example 4 of the present invention, (A) CUR probe composition; (B) NR probe composition.

[0097] Figure 7 2 is a graph showing the fluorescence response value-detergent concentration curve when two ACQ fluorescent probe compositions are used to test the cmc of detergent solutions or washing water in different scenarios in Example 5 of the present invention, (A) CUR probe composition; (B) NR probe composition.

[0098] Figure 8 2 is a graph showing the fluorescence response value-detergent concentration curve when the cmc of other types of products containing surfactant ingredients (softener, oxygen bleach, disinfectant) are tested using two ACQ fluorescent probe compositions in Example 6 of the present invention, (A) CUR probe composition; (B) NR probe composition. DETAILED DESCRIPTION

[0099] Hereinafter, specific embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments at all and can be implemented with appropriate modifications within the scope of the purpose of the present invention.

[0100] In the present specification, a numerical range expressed using "to" means a range including the numerical values ​​described before and after "to" as the minimum value and the maximum value, respectively. Unless otherwise specified, the maximum value and the minimum value indicating each preferred range can be combined with each other.

[0101] In this specification, "surfactant solution" refers to an aqueous solution containing a surfactant. When the surfactant is used to wash clothes or articles (referred to as clothing or laundry), the surfactant is referred to as a "detergent", and the aqueous solution of the surfactant is referred to as a "detergent solution" or "washing water". Specifically, an aqueous solution prepared by directly preparing and diluting a detergent with water is referred to as a "detergent solution", including an aqueous solution obtained by adding detergent and water to an inner drum of an industrial washing machine or a domestic washing machine but without adding clothes or fabric loads; on the other hand, a detergent solution obtained by putting clothes or fabrics in an industrial washing machine or a domestic washing machine, adding detergent and water, and mixing the detergent and water through the inner drum is referred to as "washing water". In addition, regarding the concentration of the surfactant, when there are multiple surfactant components in the surfactant solution, unless otherwise specified, it refers to the total concentration of the multiple surfactant components present in the surfactant solution.

[0102] In this specification, the “fluorescence response value” refers to the FL fluorescence intensity (au) when measured using a fluorescence spectrophotometer, and refers to the response voltage value (V) when measured using a fluorescence photodetector (abbreviated as CD detector).

[0103] In addition, in this specification, the unit of Hansen solubility parameter HSP value (δd, δp, δh) and HSP distance Ra is (MPa). 1 / 2 However, for the sake of simplicity, the units of Ra value and HSP value are sometimes omitted and only numerical values ​​are expressed.

[0104] (ACQ fluorescent probe composition)

[0105] The ACQ fluorescent probe composition of the present invention is characterized in that: it is a probe solution for directly measuring the cmc concentration of a surfactant, comprising a probe molecule and an auxiliary agent, wherein the probe molecule is a fluorescent molecule having an aggregation-induced luminescence quenching (ACQ) property, and the auxiliary agent comprises one or more non-volatile organic solvents, wherein the boiling point of the organic solvent is above 100°C; and the distance Ra between the Hansen solubility parameter of the probe molecule and the organic solvent is within 17 (MPa). 1 / 2 the following.

[0106] In the present invention, "direct determination" means that the ACQ fluorescent probe composition of the present invention can be directly added to the test solution in the state of probe solution without pretreatment (such as waiting for the organic solvent to evaporate after adding the test solution) for subsequent cmc determination.

[0107] In the present invention, "non-volatility" refers to the property of an organic solvent that its volume remains unchanged after long-term storage at room temperature and pressure. Generally, the higher the boiling point of an organic solvent, the lower its volatility. Therefore, in the present invention, the boiling point of the organic solvent contained in the auxiliary agent is specified to be above 100°C, so that it has non-volatility. When the organic solvent is non-volatile, it can be considered that the probe solution formed by dissolving the probe of the present invention in the auxiliary agent is a stable solution and can be stored for a long time.

[0108] In the present invention, the Hansen solubility parameter (HSP) is used to measure the molecular polarity and intermolecular forces of the ACQ probe molecule. In the following description, the Hansen solubility parameter is sometimes appropriately expressed as "HSP". In order to form a stable probe solution in an aqueous system of a surfactant solution and to show obvious aggregation-induced luminescence quenching (ACQ) phenomenon at a suitable cmc concentration, the Hansen solubility parameter δ of the ACQ probe molecule of the present invention is preferably set to 15 (MPa) 1 / 2 ~35(MPa) 1 / 2 , more preferably 20 (MPa) 1 / 2 ~25(MPa) 1 / 2 In the present specification, the unit of the Hansen solubility parameter may be omitted and expressed, that is, the Hansen solubility parameter δ is preferably 15 to 35, and more preferably 20 to 25.

[0109] Furthermore, the distance Ra of the Hansen solubility parameter (HSP) can be used to predict the solubility of the ACQ probe molecule in an organic solvent. Generally, when the absolute value of the HSP distance Ra between the ACQ probe molecule and the organic solvent is less than 17, it can be considered that the ACQ probe molecule can be fully dissolved in the organic solvent to form a relatively stable probe solution.

[0110] In the auxiliary agent of the present invention, the organic solvent that meets the above requirements can be used only one or in combination of multiple. In addition, without affecting the solubility of the probe or the accuracy of the cmc measurement result, in addition to the above-mentioned non-volatile organic solvent as an essential component, the auxiliary agent can also contain a small amount of volatile organic solvent or inorganic solvent (such as water) as an optional component. That is to say, in the present invention, the auxiliary agent can be only one organic solvent, a mixed solvent of multiple organic solvents, or a mixed solvent of an organic solvent and an inorganic solvent.

[0111] There is no particular limitation on the content of the non-volatile organic solvent contained in the auxiliary agent. As an essential component, its content exceeds 0%, and can be 10% by volume or more, preferably 30% by volume or more, more preferably 50% by volume or more, further preferably 70% by volume or more, further preferably 90% by volume or more, and most preferably 100% by volume.

[0112] In order to form a stable and clear probe solution with sufficient probe stock solution concentration, the ACQ probe molecule of the present invention must have good solubility in the organic solvent used as an auxiliary agent.

[0113] When the ACQ probe molecule is soluble in an auxiliary agent, the cmc can sometimes be determined even with a low solubility, so the conventional quantitative description of solubility may not be able to accurately characterize it, and considering the applicability to different probe molecules, in the present invention, the concept of solubility grading is used to qualitatively classify the solubility of the ACQ probe molecules.

[0114] According to the reference standard of solubility classification recorded in Table 1 below, the solubility classification of the ACQ probe molecule of the present invention in the auxiliary agent is "soluble" or above, preferably "relatively soluble" or above, and more preferably "soluble". That is, the solubility of the ACQ probe molecule in the auxiliary agent is ≥ 0.1 mg / ml (≥ 0.01%), preferably ≥ 1 mg / ml (≥ 0.1%), and more preferably ≥ 10 mg / ml (≥ 1%).

[0115] Taking CUR (curcumin) molecule as an example, if its solubility in a specific solvent at room temperature is ≥0.1 mg / ml (i.e. ≥0.01%), it can be judged that its solubility classification is above "soluble" in the specific solvent, and the CUR molecule can be used as a probe to form the ACQ fluorescent probe composition of the present invention with the specific solvent. In fact, in the present invention, when CUR is formulated into a probe solution with a concentration of 1.0 mg / ml, it can exhibit suitable fluorescence properties and perform cmc measurement.

[0116] Table 1

[0117]

[0118] In the fluorescent probe composition of the present invention, since the ACQ probe molecules are dissolved in the auxiliary agent, and the auxiliary agent contains a non-volatile organic solvent with a boiling point of more than 100°C, a stable and homogeneous probe solution can be formed, which is convenient for long-term storage and preservation, and the volume will not decrease or the concentration will not change even after long-term storage. In addition, the fluorescent probe composition can be transferred and taken out before use, and can be directly used to determine the cmc concentration of the surfactant without the volatilization of the solvent, which shortens the operation time. In addition, if the ACQ molecules are not dissolved in the organic solvent and added directly, the amount of probe added will be inaccurate and the mixing will be uneven, affecting the accuracy of the cmc measurement results. Since the fluorescent probe composition of the present invention exists in the form of a solution, a sampling mechanism (such as a peristaltic pump and matching pipelines) can be used for accurate weighing, transfer and sample addition, which is easy to operate.

[0119] As practical uses of the ACQ fluorescent probe composition of the present invention, it can be listed that the ACQ fluorescent probe composition is used as a probe solution to perform CMC measurement of a surfactant solution, or to determine whether stains on clothes with different stains can be washed, thereby providing a suitable judgment basis for the detergent dosage control method of the washing machine.

[0120] Hereinafter, various components contained in the ACQ fluorescent probe composition of the present invention will be described in detail.

[0121] [ACQ molecule]

[0122] The probe molecule of the present invention is a fluorescent molecule with ACQ property.

[0123] Aggregation-Caused Quenching (ACQ) is a phenomenon that ACQ fluorescent molecules have, that is, the fluorescent molecules emit light in a dilute solution state, and once they aggregate or become solid, their fluorescence intensity is significantly weakened or even disappears. Common ACQ molecules include curcumin, fluorescein, rhodamine, Nile red, pyrene, perylene, etc. These molecules usually have a planar conjugated system and are relatively rigid. In good solvents and low-concentration solutions, fluorescent molecules exist as independent molecules and can emit strong fluorescence after being excited by specific light; in poor solvents or when the concentration increases to a certain level and aggregates, the intermolecular π-π force increases, and most of the excitation energy is converted into non-radiative transitions (such as molecular thermal motion, etc.) and released, causing the fluorescence to weaken or disappear.

[0124] ACQ molecules in different aggregation or dispersion states in solutions and micelles exhibit completely different fluorescence properties, including fluorescence emission intensity (none / weak / strong) and characteristic wavelength (spectral blue shift / unchanged / red shift). Based on these characteristics, it can be used as a probe to determine the cmc of surfactant solutions.

[0125] In the present invention, hydrophobic ACQ molecules can be used for the determination of cmc, and these ACQ molecules are dissolved in a suitable organic solvent as probes to form a probe solution, i.e., an ACQ fluorescent probe composition. When such a probe solution is added to water or an aqueous solution of a low concentration of a surfactant, the ACQ molecules exist in an aggregated form due to their hydrophobicity, and at this time, there is no fluorescence or low fluorescence, but when the surfactant reaches the cmc concentration and forms micelles, the hydrophobic core of the micelles can serve as a good solvent for the ACQ fluorescent molecules and promote their dissolution, and when the ACQ molecules are dissolved in the micelles in the form of single molecules, they will emit strong characteristic fluorescence, thereby showing obvious ACQ characteristics within a suitable concentration range.

[0126] In addition, some hydrophilic or partially hydrophilic ACQ molecules can also be used for the determination of cmc. For example, Rhodamine B is a hydrophilic ACQ molecule that can be completely dissolved in water to form a homogeneous and stable solution. In an aqueous solution, a low concentration of Rhodamine B is in a dispersed state in the aqueous solution and can emit strong fluorescence, while when the concentration is too high, it aggregates without fluorescence, which is consistent with the ACQ characteristics of dissolving and dispersing fluorescence in a dilute concentration and good solvent and quenching in an aggregated state. The inventor speculates that the mechanism is: the hydrophilic-hydrophobic amphiphilic structure of Rhodamine B enables it to be inserted into the micelle fence layer of the surfactant and participate in the formation of micelles, wherein the hydrophilic end is located in the hydrophilic surface layer of the micelle, and the hydrophobic end stays in the fence layer, and the fluorescence intensity is enhanced or the fluorescence wavelength is shifted due to the increase in local concentration, thereby showing different fluorescence characteristics in different systems with / without micelles. However, referring to its structural characteristics and pH test results, the accuracy of the measurement results of Rhodamine B as a probe may be greatly affected by the pH value of the solution.

[0127] As described above, the luminescence mechanism of the ACQ probe molecules that can be used in the present invention can be based not only on the change in fluorescence intensity caused by solubilization of the hydrophobic core, but also on the red-shift / blue-shift of the characteristic emission wavelength caused by the amphiphilic structure of the molecule entering the fence layer or the interior of the micelle. That is, the luminescence strategy of the ACQ probe molecules of the present invention is based on but not limited to the change in fluorescence intensity or the change in characteristic wavelength, wherein the change in fluorescence intensity can be a change from none to one or from weak to strong, and the change in characteristic wavelength includes a change in wavelength red-shift (Red-Shift) or wavelength blue-shift (Blue-Shift).

[0128] That is, the ACQ probe molecules of the present invention include ACQ molecules having a blue-shifted characteristic at a characteristic wavelength, ACQ molecules having a red-shifted characteristic at a characteristic wavelength, and ACQ molecules having a constant characteristic at a characteristic wavelength. Specific examples include pyrene, Nile red, curcumin, coumarin, 8-anilino-1-naphthalenesulfonate sodium, N-phenyl-1-naphthylamine, rhodamine B, dansyl chloride, 6-propionyl-2-(dimethylamino)naphthalene, neutral red, fluorescein, anthracene, lycopene, etc., preferably Nile red, curcumin, coumarin, N-phenyl-1-naphthylamine, rhodamine B and pyrene, etc., and more preferably ACQ molecules having a constant characteristic wavelength or having a blue-shifted characteristic, such as curcumin, Nile red, coumarin, etc.

[0129] The inventors first preliminarily screened several commonly used fluorescent probe molecules according to the requirements of easy availability and low toxicity of fluorescent reagents, including the following substances: PYR (pyrene): it is a molecule with fluorescent properties and is often used in the study of biological markers and fluorescent probes; NR (Nile Red): it is a common lipophilic fluorescent dye, which is often used for staining lipid substances such as lipids; CUR (Curcumin): it is a multi-purpose natural fluorescent probe and drug molecule; C480 (Coumarin): it is a common (heavy) metal detection fluorescent probe; ANS (sodium 8-anilino-1-naphthalenesulfonate): it is a fluorescent probe widely used in the study of protein structure and conformational changes; NPN (N-phenyl-1-naphthylamine): it is a commonly used fluorescent dye with a wide range of applications, including biomedicine, material science and chemical analysis; RhB (Rhodamine B): it is a cell fluorescent stain commonly used in laboratories.

[0130] The chemical structures of these fluorescent molecules are shown below:

[0131]

[0132]

[0133] In order to determine whether these fluorescent probe molecules can form a stable probe solution, the inventors dissolved these probe molecules in N-methylpyrrolidone (NMP). The results showed that they could form clear solutions and emit fluorescence of various colors in the solution state.

[0134] Using the above-prepared probe solution, detergent solutions formulated at a series of concentrations (including the directly prepared Supreme Clean solution and the Supreme Bright Wash water containing a fluorescent brightener) were tested. Specifically, according to the measurement results of the fluorescence spectrophotometer, an appropriate wavelength was selected, and a fluorescence response value-concentration curve graph with the detergent concentration on the abscissa and the fluorescence intensity on the ordinate was plotted. The change interval where the curve transitions from the plateau region to the rising region was visually determined, corresponding to the range of values for the cmc measurement. The results are shown in Table 2 below.

[0135] Meanings of the abbreviations in Table 2: PYR: pyrene; ANS: 8-anilino-1-naphthalenesulfonic acid; NPN: N-phenyl-1-naphthylamine; C480: coumarin 480 (density 1.3 g / cm 3 ); CUR: curcumin; NR: nile red. " / " indicates not measured. In addition, the meanings of the comprehensive evaluation column in the table are as follows: ×: not measurable; △: available, but with large errors or weak anti-interference ability; ○: preferred result; ◎: more preferred result.

[0136] In addition, the spectral parameters of various probes, the values of the solubility parameter δ, the changes in characteristic wavelengths, and the cmc control results measured by the surface tension method are also shown in Table 2.

[0137] Table 2

[0138]

[0139] * The solubility parameter δ values of PYR, CUR, and RhB are reported values in the literature. The solubility parameter δ values of the remaining probe molecules are HSP values calculated based on the functional group contribution method. There is no numerical reference for the sulfonic acid functional group in ANS, and it is calculated based on the phosphoric acid functional group.

[0140] As shown in Table 2, the characteristic wavelength of the fluorescent probe molecule may change before and after the cmc of the surfactant. △λ = λ (surfactant concentration ≥ cmc) - λ (surfactant concentration < cmc). When △λ > 0, it is a red shift (i.e., the wavelength becomes larger); when △λ < 0, it is a blue shift (i.e., the wavelength becomes smaller); when △λ = 0, the wavelength remains unchanged.

[0141] The results in Table 2 show that in the system of probe composition with NMP as the auxiliary agent, the fluorescence response value of the water-soluble ANS probe is basically linear with the detergent concentration, with no obvious inflection point, so it is difficult to measure cmc; PYR and NPN can be used as probes to measure cmc in the directly prepared Supreme Clean Solution, and the deviation of the measurement results is small, but the measurement results of PYR in the actual Supreme Bright Whitening washing water are affected by various factors and have a large deviation. NPN is greatly affected by the fluorescent whitening agent in the measurement of Supreme Bright Whitening washing water, resulting in the inability to measure cmc. The comprehensive evaluation results show that the four fluorescent molecules C480, CUR, NR, and RhB are suitable for measuring the cmc concentration of surfactant solutions or actual washing water in the system with NMP as the auxiliary agent, and are preferred ACQ molecules.

[0142] It can also be seen from Table 2 that the deviations of the determination results of RhB and C480 are slightly larger. The more preferred ACQ molecules in the present invention are curcumin CUR and Nile red NR. The cmc value ranges measured by the two for the directly prepared supreme clean solution (excluding fluorescent whitening agents) can verify each other, and are consistent with the results measured by the surface tension method (0.066g / L), with high accuracy. Moreover, in the actual use of the supreme bright white washing water containing fluorescent whitening agents, the cmc value ranges measured by the two are also consistent with the results measured by the surface tension method (0.3g / L), and are not interfered by the fluorescent whitening agents (CBS or FB-33) contained therein. The inventors speculate that this is because the Ex / Em of fluorescent whitening agent 33# (FB-33) is 370 / 430nm, and the Ex / Em of sodium distyryl biphenyl disulfonate (CBS) is 340 / 425nm; and the emission peak of NR is at 638nm, which is not within the emission peak range of the fluorescent whitening agent, so NR is not affected by it; although the emission wavelength of CUR falls within the fluorescent emission peak range of the fluorescent whitening agent, the response of the fluorescent whitening agent at its excitation wavelength of 430nm is not obvious, that is, the fluorescent whitening agent has no fluorescent emission at this excitation wavelength, so the interference of the fluorescent whitening agent can also be avoided.

[0143] In the present invention, the Hansen solubility parameter (HSP) δ is used to measure the molecular polarity and intermolecular forces of the ACQ probe molecule. Referring to the data in Table 2, it can be seen that the solubility parameter δ of the ACQ probe molecule that can form a stable probe solution is roughly in the range of 15 to 35. Therefore, the Hansen solubility parameter δ of the ACQ probe molecule is preferably 15 to 35. In addition, from the perspective of the accuracy of the cmc measurement, the solubility parameter of the ACQ probe molecule is more preferably in the range of 20 to 25.

[0144] The above screening results are only an example of the ACQ fluorescent probe composition of the present invention. When different organic solvents are used as auxiliary agents, different ACQ fluorescent probe compositions may exhibit different fluorescence properties and ACQ characteristics. Therefore, the ACQ fluorescent molecules used in the present invention are not limited to the above-mentioned RhB, C480, CUR and NR, and the auxiliary agent is not limited to NMP. A specific combination of suitable ACQ fluorescent molecules and auxiliary agents can be screened out according to specific application scenarios and needs.

[0145] [Additives]

[0146] The auxiliary agent in the ACQ fluorescent probe composition of the present invention comprises one or more non-volatile organic solvents. The type of the organic solvent mainly depends on its own volatility, as well as the solubility and fluorescence properties of the ACQ molecule in the organic solvent.

[0147] In the present invention, when the auxiliary agent contains only one organic solvent, the properties of the auxiliary agent (viscosity, density, flash point, etc.) refer to the properties of the organic solvent; when the auxiliary agent is a mixed solvent of multiple organic solvents or a mixed solvent of an organic solvent and an inorganic solvent, the properties of the auxiliary agent refer to the properties of the mixed solvent.

[0148] In the prior art, in order to use ACQ molecules as probes to measure cmc, ACQ molecules are usually pre-dissolved in volatile organic solvents, such as methanol, ethanol, benzene, tetrahydrofuran, dioxane, etc., and then the organic solvents are removed before measurement. However, these organic solvents are highly volatile colorless liquids with low boiling points and flash points. If the probe solution of the present invention is prepared, the mother solution is not easy to store for a long time after preparation, and the solution volume and probe concentration are prone to change.

[0149] The inventors used curcumin CUR as a specific probe molecule, and through research and screening of the physical properties of a series of organic solvents, found some specific organic solvents that can be used as adjuvants for the above-mentioned ACQ molecules. These organic solvents have sufficient solubility for ACQ molecules, are not easily volatile, and can make curcumin CUR exhibit obvious ACQ characteristics within a suitable concentration range of a specific surfactant solution.

[0150] Various parameters such as volatility, water solubility, density, viscosity and probe solubility of a series of organic solvents investigated by the inventors are shown in Table 3.

[0151] Table 3. Properties of each solvent

[0152]

[0153] *1The ACQ probe molecule is CUR, and its solubility is as described above, where >1% is easily soluble, 0.1-1% is relatively soluble, 0.01-0.1% is soluble, and <0.01% is poorly soluble / insoluble.

[0154] *2 The solubility of solvents in water is graded with reference to the solvent data in Pub Chem, where >10% is readily soluble, 1-10% is soluble, 0.01-1% is slightly soluble, and <0.01% is poorly soluble / insoluble.

[0155] In order to form a stable probe solution that is convenient for long-term storage, the auxiliary agent in the ACQ fluorescent probe composition of the present invention must contain one or more non-volatile organic solvents.

[0156] In the present invention, the boiling point value is used to evaluate the volatility of the organic solvent. Generally speaking, the lower the boiling point of the organic solvent, the greater its volatility. As can be seen from Table 3, the volatile organic solvents (acetone, etc.) commonly used in the art have low boiling points and are too volatile, and are not suitable for use as auxiliary agents for the stable probe solution of the present invention.

[0157] As a suitable auxiliary agent, the boiling point of the nonvolatile organic solvent of the present invention is specified to be 100° C. or higher, preferably 120° C. or higher, and more preferably 150° C. or higher.

[0158] In addition, in order to form a uniform, clear solution with sufficient probe concentration, the ACQ probe molecule of the present invention must have good solubility in the organic solvent used as an auxiliary agent, and the solubility grade of the probe is preferably at least soluble, that is, the solubility of the probe molecule in the organic solvent is preferably above 0.1 mg / ml (0.01%).

[0159] When screening suitable organic solvents for selected probe molecules, it is difficult to conduct solubility tests on each of a large number of solvents. If the solubility of the solvent relative to the probe can be evaluated and predicted in advance, the time and cost required for screening auxiliary agents can be greatly reduced.

[0160] In the present invention, in order to establish the intrinsic relationship between the microstructure and macroscopic solubility of the probe molecule, the Hansen Solubility Parameter theory (HSP theory) is used to evaluate and predict the solubility of ACQ molecules in organic solvents.

[0161] There are many ways to calculate solubility parameters. In the HSP theory, the surface energy of solutes and solvents is classified by three energy terms. These three energy terms are dispersion δd, polarity δp, and hydrogen bond δh, and the unit is MPa. 1 / 2Based on the HSP theory, if the HSP value of the solute is (δd1, δp1, δh1) and the HSP value of the solvent is (δd2, δp2, δh2), then the distance Ra of the Hansen solubility parameters between the solute and the solvent (abbreviated as HSP distance Ra) can be expressed by the following formula 1.

[0162] Ra 2 =4(δd1-δd2) 2 +(δp1-δp2) 2 +(δh1-δh2) 2 (Formula 1)

[0163] The smaller the HSP distance Ra is, the easier it is for the solute to dissolve in the solvent. In the probe-organic solvent system, the organic solvent is the dispersion medium, and the probe molecule as the solute is the dispersed phase. Generally speaking, a dispersed state can be obtained when Ra≤20, a medium dispersed state can be obtained when Ra≤15, a high dispersed state can be obtained when Ra≤10, and an ultra-high dispersed state can be obtained when Ra≤5. By comparing the Ra values ​​between the solute and different solvents, a solvent with similar interaction force with the solute can be found to obtain a higher solubility.

[0164] The inventors took the probe molecule curcumin (CUR) as an example of solute and investigated the literature values ​​or calculated values ​​of the solubility parameters of various organic solvents or mixed solvents of organic solvents and inorganic solvents, as well as the measured results of solubility fractionation. The results are shown in Table 4-1 below.

[0165] Table 4-1 Solubility parameters of curcumin (CUR) and various solvents

[0166]

[0167] *: Indicates that the listed δ values ​​are calculated values, where the δ value of a single solvent is calculated based on the functional group contribution method, and the δ value of a mixed solvent is calculated based on the δ value of a single solvent and the solvent ratio contribution method.

[0168] It can be seen from Table 4-1 that, except for a few non-polar organic solvents (such as cyclohexane and toluene), the HSP distance Ra value has a roughly corresponding relationship with the measured solubility classification. Among them, the vast majority of organic solvents or mixed solvents with HSP distance Ra values ​​below 17 have good solubility for the ACQ probe molecule (CUR), and their solubility classification is soluble or above; when the Ra value is below 15, preferably below 12, the solubility of the ACQ probe molecule in the solvent predicted by the HSP distance Ra value is more consistent with the results of the measured solubility classification.

[0169] Therefore, in the present invention, in order to obtain good probe solubility, the HSP distance Ra value between the ACQ probe molecule and the organic solvent or mixed solvent as an auxiliary agent is set to 17 or less, preferably 15 or less, and more preferably 12 or less.

[0170] However, predicting the solubility by the HSP distance Ra value sometimes produces certain errors. For example, the HSP distance Ra value (16.858) between acetonitrile and the probe molecule is much larger than the HSP distance Ra value (3.753) between n-octanol and the probe molecule. However, from the measured results, the solubility of acetonitrile to the probe molecule is significantly better than that of n-octanol to the probe molecule. The reason is still unclear, and it may be due to the influence of intermolecular forces (such as hydrogen bonds), polarity or molecular conformation on solubility. For this reason, we further introduce the difference △δ of the Hansen solubility parameter δ to correct the prediction results.

[0171] According to the solubility parameter theory proposed by Hildebrand, the total δ value of the solubility parameter (abbreviated as δ) is the vector sum of the three components of dispersion δd, polarity δp, and hydrogen bond δh (see formula 2 below). When the difference between the total δ of the solute and the solution, that is, the δ difference (△δ), is less than a constant value, the solution is relatively stable, which is the so-called compatibility theory.

[0172] δ 2 =δd 2 +δp 2 +δh 2 (Formula 2)

[0173] It can be seen from Table 4-1 that the total δ value of the CUR molecule as the ACQ probe molecule is 22.579, while the total δ values ​​of most organic solvents or mixed solvents that have good solubility for the CUR molecule (solubility classification is soluble or above) are in the range of 19 to 34.

[0174] Therefore, in the present invention, from the perspective of compatibility between the solute and the solvent, the δ difference between the total δ of the organic solvent or mixed solvent as the auxiliary agent and the total δ of the ACQ probe molecule (i.e., △δ = total δ of the auxiliary agent - total δ of the ACQ probe molecule) is preferably in the range of -3 to +12, more preferably in the range of -2.5 to +10, further preferably in the range of -2 to +4, and further preferably in the range of -2.0 to +2.5. Furthermore, from the perspective of making the formed probe solution more stable, the absolute value of the δ difference is preferably less than 2, and more preferably less than 1.

[0175] As can be seen from Table 4-1, firstly, from the requirement that the organic solvent is non-volatile, acetone, acetonitrile, and ethanol (see Table 3) need to be excluded. Secondly, organic solvents or mixed solvents that simultaneously meet the requirements that the HSP distance Ra of the organic solvent is less than 17 and the δ difference is -3 to +12 include: dibutyl phthalate, n-octanol, polyethylene glycol 200 (PEG200), diethylene glycol ethyl ether (DGME), ethylene glycol monophenyl ether, N-ethyl pyrrolidone (NEP), N-methyl pyrrolidone (NMP), n-butanol, ethyl glycolate, dimethylformamide (DMF), dimethyl sulfoxide, 1,5-pentanediol, 1.3-butanediol (1,3-BDO), ethylene glycol, and mixed solvents of specific proportions of these organic solvents (such as DGME, 1,3-BDO, NMP) and water, etc. These solvents have good solubility and compatibility for the ACQ probe molecules of the present invention and can be used as the auxiliary agent of the present invention.

[0176] Furthermore, as the preferred auxiliary agent of the present invention, the solvents that simultaneously meet the requirements of the HSP distance Ra of the organic solvent being less than 15, the δ difference being -2.5 to +10, and the non-volatility include: dibutyl phthalate, n-octanol, polyethylene glycol 200 (PEG200), diethylene glycol ethyl ether (DGME), ethylene glycol monophenyl ether, N-ethyl pyrrolidone (NEP), N-methyl pyrrolidone (NMP), n-butanol, ethyl glycolate, dimethylformamide (DMF), dimethyl sulfoxide, 1,5-pentanediol, 1,3-butanediol (1,3-BDO), and the mixtures of these organic solvents and water. Mixed solvents with specific ratios, such as a mixed solvent of DGME and water (9:1), a mixed solvent of DGME and water (7:3), a mixed solvent of 1,3-BDO and water (8:2), etc.; as more preferred auxiliary agents of the present invention, solvents that simultaneously satisfy the HSP distance Ra of the organic solvent being less than 12 and the δ difference being in the range of -2.0 to +2.5 include: diethylene glycol ethyl ether (DGME), ethylene glycol monophenyl ether, N-ethylpyrrolidone (NEP), N-methylpyrrolidone (NMP), n-butanol, a mixed solvent of DGME and water (9:1), and dimethylformamide (DMF).

[0177] The range of organic solvents selected by the above method is basically consistent with the range of organic solvents subsequently screened by the inventors through a large number of experiments. Therefore, the present invention can predict and screen a suitable combination of ACQ probe molecules and auxiliary agents by combining the boiling point of the organic solvent and the solubility parameter δ of the probe molecule and the organic solvent.

[0178] That is to say, when determining the combination of the probe and the auxiliary agent in the ACQ fluorescent probe composition of the present invention, the volatility of the auxiliary agent itself is first considered. With reference to the boiling point value of the solvent, a large number of organic solvents can be selected as alternative auxiliary agents. Then, by pre-checking or calculating the values ​​of the solubility parameters of the selected probe molecule and the alternative organic solvent, the solubility and compatibility of the probe molecule in various auxiliary agents can be better predicted, thereby greatly improving the screening efficiency of the auxiliary agent and saving costs, which has important guiding significance in the preparation of the ACQ fluorescent probe composition of the present invention.

[0179] Generally speaking, the HSP values ​​(δd, δp, δh) of most small molecules can be found in the literature, while polymers usually need to be calculated. The values ​​of δd, δp, and δh of different substances can be queried through the Hansen Solubility Parameters manual and the appendix of Edproperties of polymer, or calculated based on the functional group contribution method, but this calculation method does not take into account the intermolecular effect, so the δh value may be too low.

[0180] When preparing the ACQ fluorescent probe composition of the present invention, for the organic solvent in the auxiliary agent, in addition to requiring non-volatility and good solubility in the probe, other properties of the auxiliary agent (such as viscosity, water solubility, density, flash point, etc.) need to be considered.

[0181] From the perspective of easy and uniform dispersion of the prepared probe solution, convenient sampling and accurate weighing, the viscosity of the organic solvent used as an auxiliary agent is preferably 30 mPa·s or less, more preferably 25 mPa·s or less, and further preferably 10 mPa·s or less.

[0182] For organic solvents with high viscosity, the viscosity can also be reduced by combining multiple solvents to form a mixed solvent. For example, the viscosity of 1,3-butanediol (1,3-BDO) is 130 mPa·s. By adding a certain proportion of low-viscosity solvents such as NMP, DGME or water to it to make a mixed solvent, its viscosity can be significantly reduced.

[0183] In order to form a stable solution system to be tested, the organic solvent is preferably miscible with water. In the present invention, "miscible with water" means that the organic solvent has a certain solubility in water, specifically, it can be slightly soluble, soluble or easily soluble in water (see Table 3).

[0184] In addition, in order to uniformly disperse the probe solution in the surfactant solution when measuring cmc, the density of the organic solvent in the auxiliary agent is preferably 0.9 to 1.2 g / cm 3In this way, the probe solution can be easily evenly diffused in water; if the density difference between the organic solvent and water is large, uneven diffusion is likely to occur. Since the probe solution is generally added from above the liquid to be tested, the density of the organic solvent can be slightly greater than the density of water, preferably controlled at 1.2 g / cm 3 If the density is less than 0.9g / cm 3 , it is easy to float above the aqueous solution, which is not conducive to the diffusion of probe molecules in the aqueous solution.

[0185] The density of the mixed solvent can be adjusted by combining multiple solvents. For example, the density of n-butanol is only 0.811 g / cm 3 , can be mixed with solvents with higher density such as ethylene glycol or NMP to obtain a mixed solvent with suitable density.

[0186] In addition, from the perspective of safety, the auxiliary agent of the present invention is preferably a low-toxic, slightly toxic or non-toxic organic solvent with a flash point of 60° C. or higher, preferably 70° C. or higher, and more preferably 75° C. or higher.

[0187] Similarly, a combination of multiple solvents can also be used to adjust the flash point of the mixed solvent. For example, n-butanol has a better solubility (more soluble) for the probe (CUR), but its flash point is relatively low, only 37°C, while ethylene glycol has a slightly worse solubility for the probe (CUR), but its flash point is 110°C. Therefore, by mixing a small amount of n-butanol (e.g., 995 ethylene glycol-5 n-butanol (v / v)) into ethylene glycol, a good balance can be achieved in terms of solubility and flash point properties.

[0188] Taking into account the various property parameters of the organic solvent, it can be known that the auxiliary agent of the present invention is preferably selected from one or more of n-butanol, ethylene glycol, NMP, NEP, DMF, DGME, ethyl glycolate, polyethylene glycol 200, 1.3-butanediol and 1,5-pentanediol, more preferably selected from one or more of n-butanol, ethylene glycol, NMP, NEP, DGME, polyethylene glycol 200, more preferably NMP, NEP, DGME, polyethylene glycol 200.

[0189] In addition, when the type of ACQ molecule changes, the preferred range of the corresponding auxiliary agent may also change accordingly, as mentioned above, which mainly depends on the matching degree of the solubility parameters of the two.

[0190] For example, when pyrene or rhodamine B is used as the solute, the solubility parameters in Table 4-2 and Table 4-3 below can be used to evaluate and predict its solubility in various solvents.

[0191] Table 4-2 Solubility parameters of pyrene in various solvents

[0192]

[0193] Table 4-3 Solubility parameters of Rhodamine B in various solvents

[0194]

[0195] In Table 4-3, the HSP distance Ra between Rhodamine B and water is 23.968, but it is "soluble" in water. The inventors speculate that the reason may be that Rhodamine B itself is an ionic form of a quaternary ammonium salt, and the tertiary amine groups it contains can form hydrogen bonds after protonation in an aqueous solution, that is, there is a strong intermolecular interaction between Rhodamine B and water, but this strong interaction cannot be taken into account when calculating using HSP parameters, so the calculated results are not completely consistent with the actual test results.

[0196] When determining the specific combination of fluorescent molecules and auxiliary agents in the ACQ fluorescent probe composition of the present invention, unlike the AIE fluorescent probe composition we studied before, which focuses on the hydrophilic-hydrophobic amphiphilic molecular structure of the auxiliary agent, the present invention pays more attention to the differences in solubility, dispersibility, molecular polarity and other properties between the auxiliary agent and the ACQ molecule. This may be because most AIE molecules are non-polar macromolecular structures, and the auxiliary agent has a hydrophilic-hydrophobic amphiphilic structure, which is adsorbed on the surface of the AIE molecule through the hydrophobic part to form a hydrophilic layer, which is conducive to its stable dispersion in the aqueous system. Dispersed, therefore, in a low concentration surfactant solution, the AIE molecules exist in a dispersed state and do not emit light. When the concentration exceeds the cmc and micelles are formed, the auxiliary agent follows the AIE molecules into the fence layer of the micelles and aggregates to emit light; in the fluorescent probe composition of the present invention, the auxiliary agent has a high solubility in water, and there is a competitive relationship between the dissolution of the auxiliary agent and the ACQ molecules in the hydrophilic-hydrophobic system. When the ACQ fluorescent probe composition is added to the surfactant solution or washing water, the diffusion rate of the auxiliary agent is significantly faster than that of the ACQ probe molecules. The auxiliary agent is preferentially dissolved in water, while the probe tends to aggregate in water due to its hydrophobicity. Since the auxiliary agent molecules can only affect the solubility and stability of the ACQ probe molecules in water to a certain extent, in a low concentration surfactant solution, the ACQ probe molecules exist in an aggregated state and do not emit light. When the concentration of the surfactant exceeds the cmc and micelles are formed, the auxiliary agent cannot follow the ACQ molecules into the micelles, and the ACQ molecules enter the interior of the micelles in the form of monomers and emit light.

[0197] [Other ingredients]

[0198] The ACQ fluorescent probe composition of the present invention may include, in addition to the ACQ molecules and auxiliary agents as probes, other components such as stabilizers, preservatives and other additives without affecting the ACQ effect.

[0199] When other components are contained, the total content of other components is preferably less than 5% by mass, more preferably less than 1% by mass, based on the total amount of the ACQ probe composition.

[0200] [ACQ fluorescent probe composition]

[0201] The ACQ fluorescent probe composition of the present invention comprises ACQ molecules as probes and auxiliary agents, wherein the auxiliary agents comprise one or more non-volatile organic solvents.

[0202] The fluorescence emission spectrum of ACQ molecules is one of its inherent characteristics, which is related to the fluorescent groups possessed by the molecules, but the properties of its fluorescence emission (including excitation / emission wavelength, fluorescence intensity, etc.) will change to a certain extent depending on the environment the molecules are in. Therefore, for the specific combination of ACQ molecules and additives, it is necessary to further investigate its fluorescence performance and measurement feasibility in the actual measurement environment.

[0203] The inventors used CUR and NR as specific probe compounds, and based on the screening results of the above method, studied the solubility and fluorescence properties of these two probe molecules in various solvents, and investigated the feasibility of using the ACQ fluorescent probe composition containing the probe and the auxiliary agent as a probe solution to actually determine the cmc of the surfactant solution. The results are shown in Table 5.

[0204] Table 5

[0205]

[0206] *NR is poorly soluble in EG, and a large amount of NR cannot be dissolved, resulting in extremely weak fluorescence intensity after the probe is added to the test solution when NR-EG is used as a probe composition for measurement.

[0207] In Table 5, "UV irradiation results" refers to the fluorescence emission observed when the target probe molecule (such as 1 mg / ml CUR or 1 mM NR) is dissolved in the corresponding solvent and the clarified mother liquor or the supernatant of the mother liquor is irradiated under UV light. At this time, no surfactant is added. Therefore, this result can reflect the following situations from a macroscopic perspective: 1) the solubility of the probe, 2) the homogeneity / dispersity of the probe, 3) whether there is an interaction between the probe and the solvent, and 4) the change in the peak wavelength of the fluorescence emission of the probe.

[0208] Generally speaking, only when the probe molecules have a certain solubility in the additive, good homogeneity / dispersion, and no interaction or only weak interaction with the solvent, can they emit strong fluorescence, and the color change of the fluorescence can reflect the shift of the wavelength of the maximum emission intensity of the corresponding probe.

[0209] Therefore, the “UV irradiation results” in Table 5 help illustrate the dispersibility of the probe in the solvent on a macroscopic level. For example, the probe molecules CUR and NR are strongly fluorescent in a good solvent, but non-fluorescent / weakly fluorescent in a poor solvent. At the same time, it also reflects the interaction between the solvent and the probe. For example, the benzene ring structure of ethylene glycol monophenyl ether may cause the probe molecules CUR and NR to exhibit similar aggregation quenching results, resulting in a significant reduction in fluorescence intensity.

[0210] In addition, the results of the "CMC determination" column in Table 5 refer to the feasibility of using the composition (probe solution) containing the probe molecule and the solvent for the actual measurement of CMC. Specifically, by adding the corresponding probe-solvent composition to surfactant solutions of different concentrations, the fluorescence of the homogeneously dispersed mixed solution of the probe-solvent-surfactant aqueous solution is measured to determine whether there is a fluorescence difference, so as to judge whether the CMC measurement can be achieved.

[0211] From the results in Table 5, it can be seen that when n-butanol, n-octanol, dibutyl phthalate, NMP, polyethylene glycol 200, DGME, ethyl glycolate, 1,3-butanediol, 1,5-pentanediol, etc. are used as solvents, CUR and NR can emit strong or weak fluorescence in the solvents, indicating that the probe molecules have certain solubility and dispersibility in the above solvents. When ethylene glycol is used as a solvent, CUR can be partially dissolved but the fluorescence intensity is weak, and the solubility or dispersibility of NR is poor, showing that it is difficult to dissolve and almost no fluorescence is produced by the naked eye.

[0212] In addition, although ethylene glycol monophenyl ether meets the requirements of low volatility of organic solvents and good probe solubility, the probe molecules only emit very weak fluorescence after being dissolved in ethylene glycol monophenyl ether. This may be because the benzene ring structure of the solvent molecules themselves produces an interaction force with the probe molecules, resulting in a weakened ability of the probe molecules to convert excitation light into fluorescence, so only very weak fluorescence is produced in this solvent.

[0213] Then, the same detergent (Supreme Biotechnology laundry detergent) was tested for cmc determination using various single solvents or mixed solvents in Table 5. The results show that the probe composition prepared by the three solvents of n-octanol, dibutyl phthalate and ethylene glycol monophenyl ether all had oil-water stratification of washing water solution and probe solution during the test, and the probe is more inclined to be dissolved in the organic solvent layer rather than the aqueous phase. In the case of using ethylene glycol monophenyl ether as an auxiliary agent, since ethylene glycol monophenyl ether is partially soluble in water, although stratification occurs, the cmc determination of detergent can still be achieved, and n-octanol and dibutyl phthalate are not miscible with water (see Table 3), therefore, the prepared probe solution has obvious oil-water stratification after adding surfactant solution, the density of n-octanol is relatively small, so the probe composition is in the upper layer, the density of dibutyl phthalate is relatively large, so the probe composition is in the lower layer, and the homogeneous dispersed solution cannot be obtained due to oil-water stratification, and there is no obvious fluorescence difference between the aqueous phase and the organic phase of surfactant solution of different concentrations, so cmc determination cannot be performed. This indicates that the water solubility of the auxiliary agent will also significantly affect the measurement results of the probe composition.

[0214] In addition, it can be seen from the measured results in Table 5 that when CUR and NR are used as probes and n-butanol, ethylene glycol, NMP, polyethylene glycol 200, DGME, ethyl glycolate, 1,3-butanediol, and 1,5-pentanediol are used as auxiliary agents, detectable fluorescence signal changes are produced when the probe solution is added to the aqueous solution of the surfactant, that is, the above-mentioned organic solvents can be used alone as auxiliary agents to more accurately monitor cmc.

[0215] In addition to the non-volatility of the organic solvent, the solubility of the probe, the water solubility, and the ability of the fluorescence characteristics to monitor CMC, other physical and chemical properties of the probe solution also need to be considered comprehensively, such as viscosity, density, flash point, safety, etc.

[0216] For example, although ethylene glycol, 1,3-butanediol, and 1,5-pentanediol meet the characteristics of low volatility and good water solubility, their high viscosity and low fluidity are not conducive to the dissolution, addition, and diffusion of the probe; the density of n-butanol is relatively small, and when the probe-butanol composition is added to the washing water solution, it is not easy to diffuse or diffuses slowly, which will cause uneven distribution of the probe in the solution; although ethyl glycolate meets the requirements of low volatility and probe solubility of organic solvents, and the probe solution emits strong fluorescence, its flash point is relatively low (62°C), and there are many things to pay attention to in the storage and safety of the probe composition.

[0217] Taking into account the physicochemical properties of each solvent and multiple parameters such as probe solubility, it can be seen that NMP, NEP, polyethylene glycol 200 (PEG200), and DGME are more preferred solvents screened, which can be used to directly dissolve the probe molecules and accurately monitor cmc.

[0218] In addition, when Nile Red (NR) was used as the ACQ molecule, the present inventors obtained similar screening results for the preferred adjuvant types.

[0219] Specifically, the most preferred combinations of probe + auxiliary agent in the ACQ fluorescent probe composition of the present invention include: CUR+NMP, CUR+DGME, CUR+NEP, CUR+PEG200, NR+NMP, NR+DGME, NR+NEP, NR+PEG200.

[0220] On the other hand, for single solvents such as n-butanol, ethylene glycol, ethyl glycolate, 1,3-butanediol, and 1,5-pentanediol that have some insufficient characteristics, the problem can be solved by mixing with solvents with different characteristics. For example, organic solvents such as ethylene glycol, butanediol, and pentanediol with high viscosity can be mixed with solvents such as n-butanol or DGME with good probe solubility and low viscosity in a certain proportion; organic solvents such as butanol with low density can be mixed with solvents with high density such as ethylene glycol or NMP to obtain a mixed solvent with appropriate density, so as to accelerate the diffusion rate of the probe in the washing aqueous solution, etc.

[0221] Similarly, the above-mentioned preferred solvents can also be mixed with other different types of solvents in different proportions to improve the application potential of the solvent in the probe composition, including but not limited to various physicochemical properties, safety, stability, cost, etc.

[0222] That is to say, according to the above research contents of the present invention, based on the various characteristics of the probe molecules and the organic solvents themselves, a specific combination of preferred probe molecules and auxiliary agents can be obtained directly or through appropriate adjustments.

[0223] In addition, the inventors found that the amount of probe solution, mainly the amount of organic solvent added therein, in the test solution has a certain influence on the measurement result of cmc. From the perspective of reducing the amount of organic solvent used in the probe solution and suppressing the influence on the measurement result of cmc, it is preferred to reduce the amount of organic solvent added in the surfactant solution. On the other hand, in order to ensure good fluorescence sensitivity and detection convenience, the probe solution needs to have a certain amount of addition to ensure that there is enough probe working concentration in the surfactant solution.

[0224] As shown in Table 6, the inventors investigated the effect of different solvent addition amounts of the probe solution (CUR-NMP) on the cmc test results. The test solution was Supreme Biotech (Bright White) detergent solution (ZZLB), and the detector used a customized photodetector (CD detector).

[0225] In addition, since a single organic solvent composition system of CUR-NMP is used, the amount of solvent added in Table 6 can be regarded as equivalent to the amount of probe solution added. The cmc value is determined by the fitting straight line intersection method, that is, according to the measurement results of the fluorescence spectrophotometer, a suitable wavelength in the corresponding fluorescence emission peak range is selected, and a fluorescence response value-concentration curve is drawn with the abscissa as the detergent concentration and the ordinate as the fluorescence intensity. The platform area and the rising area of ​​the curve are respectively subjected to linear regression fitting to find the intersection of the two fitting straight lines. The surfactant concentration on the abscissa corresponding to the intersection is the cmc concentration (measured value).

[0226] Table 6: Effect of solvent addition on cmc test results

[0227]

[0228] *1 The conversion method is: cmc conversion value = cmc measured value / (1 + solvent addition volume / sample volume).

[0229] *2 The cmc value was obtained by fluorescence spectrophotometry. At this time, the amount of NMP added was 40ul and the probe working concentration was 4ug / ml.

[0230] The cmc conversion value in Table 6 is the actual cmc concentration calculated after taking into account the dilution effect of the solvent on the surfactant. Specifically, cmc conversion concentration = cmc measured concentration / (1+solvent addition volume / sample volume), wherein the solvent addition volume is equivalent to the volume of the added probe solution, and the sample volume is the volume of the surfactant solution to be tested.

[0231] Since the probe solution is formed by dissolving the probe molecules in a solvent as an auxiliary agent, the amount of solvent added can be roughly regarded as the amount of probe solution added. When the amount of probe solution added is small, the cmc conversion value in the table is the same as the actual cmc measurement value. However, when the amount of probe solution added is too large, the solvent therein will produce a significant dilution of the surfactant concentration in the original test solution. Therefore, it is necessary to convert the original data as the measurement result. For example, when the amount of probe solution added is 5000ul, the cmc conversion value is 3.341=5.012 / (1+5ml / 10ml). In other words, the cmc conversion concentration has taken into account the change in solution volume and the dilution of surfactant concentration caused by the addition of the probe solution. When the amount of probe solution added is small, its dilution effect can be basically ignored.

[0232] As shown in Table 6, when using a probe solution in which the probe-adjuvant is CUR-NMP, in a 10 ml surfactant solution, the amount of solvent added in the solution to be tested is preferably no more than 1000 ul (i.e. no more than 10%), more preferably no more than 400 ul (i.e. no more than 4%), in which case the range of the cmc measured values ​​in the table is relatively stable and close to the cmc measured value (0.100 g / L) obtained using a fluorescence spectrophotometer and the cmc value (0.067 g / L) obtained by the surface tension method. When using other organic solvents, the difference in the amount of solvent added will also lead to similar results.

[0233] Therefore, in order to reduce the influence of the organic solvent in the auxiliary agent on the cmc determination result, the present invention suppresses the addition amount of the probe solution (also referred to as the probe mother solution) in the liquid to be measured to be relatively low, and its preferred range can be set with reference to the preferred range of the solvent addition amount, that is, relative to 10ml of the surfactant solution, the upper limit of the addition amount of the probe mother solution is preferably less than 1000μl, preferably less than 400μl. The lower limit of the addition amount of the probe mother solution is determined according to the sensitivity of the probe and the concentration of the probe in the probe mother solution, for example, more than 1μl, preferably more than 10μl, more preferably more than 20μl, and when the probe concentration is high, the lower limit of the addition amount of the probe mother solution can be appropriately reduced. When a mixed solvent is used, the addition amount of the probe mother solution can be converted according to the proportion of the mixed solvent and is applicable to and meets the preferred range of the organic solvent, that is, the solvent addition amount = the organic solvent ratio in the probe mother solution * the probe mother solution addition amount.

[0234] At this time, the cmc measurement results obtained by using a customized miniaturized photodetector (CD detector) in Table 6 are in the range of 0.084 g / L to 0.107 g / L, which is close to the measurement value (0.100 g / L) obtained by using a fluorescence spectrophotometer in the embodiment described later. Here, the customized miniaturized detector is a fluorescence response value detector at a specific single wavelength, and the fluorescence photometer can scan the full wavelength range of the fluorescence spectrum. Both are fluorescence detection instruments. The former is small in size, simple to operate, and has a fast detection rate, while the latter has more spectral information and higher accuracy. Both can adjust the spectral parameters according to the corresponding fluorescent probe and be used in various tests.

[0235] It can also be seen from Table 6 that the cmc test value measured by the fluorescence spectroscopy using a CD detector or a fluorescence spectrophotometer is slightly higher than the measured value (0.067g / L) of the surface tension method. The inventor speculates that the reason is that when the surfactant is saturated with adsorption on the gas-liquid surface, aggregates will begin to form in the solution. The cmc measured by the surface tension method is the concentration corresponding to the initial formation of aggregates; while the fluorescence spectroscopy method measures the concentration corresponding to the formation of a large number of aggregates in the solution and the presence of fluorescent molecules in the form of single molecules in the micelles. When micelles are just beginning to form, because the number of probe molecules may be greater than the number of micelles, there may be more than one probe molecule in each micelle, so the cmc result measured by the fluorescence spectroscopy method will be slightly greater than the cmc result of the surface tension method.

[0236] When the amount of NMP added is higher than the above range (1000ul), the cmc measurement result is significantly higher. The inventors speculate that the mechanism is as follows: NMP is a short-chain hydrophilic molecule. During the micelle formation process, the hydrophilicity of NMP will affect the hydrophobic force between the surfactant molecules, thereby affecting the micelle formation; when the NMP concentration is low, it has little effect on the cmc value measurement result. As the NMP concentration increases and exceeds a certain value, the degree to which the hydrophobic force is reduced increases significantly, thereby increasing the cmc value.

[0237] Based on the above speculation, the inventors also used the surface tension method to observe the changes in cmc values ​​of different addition amounts of NMP solvent (without probe) used in the CUR-NMP probe solution. The results are shown in Table 7. When the NMP addition amount is less than 10%, the measured cmc value is affected to a certain extent, but the impact is small; when it is less than 4%, the measured cmc value is basically unaffected. This result is basically consistent with the measurement results of the fluorescence spectroscopy method and is consistent with the inference.

[0238] Table 7: Effect of solvent addition amount on cmc results in surface tension method

[0239]

[0240] In addition, the inventors have also found that the working concentration of the probe in the test solution also has a certain influence on the measurement result of cmc. In this specification, the mother solution concentration of the probe refers to the concentration of the probe in the probe solution, and the working concentration of the probe refers to the concentration of the probe after the probe mother solution containing the probe is added to the surfactant aqueous solution or the washing water.

[0241] The inventors took the CUR-DGME probe composition as an example and conducted an experiment on the effect of the probe working concentration on the cmc measurement results. The results are shown in Table 8.

[0242] Table 8: Effect of CUR probe working concentration

[0243]

[0244] *1 It is the cmc value measured by fluorescence spectrophotometer. At this time, the amount of DGME added is 40ul and the probe working concentration is 4ug / ml.

[0245] As shown in Table 8, the probe working concentration is closely related to the results of the measured cmc concentration. When the probe working concentration in the test solution is lower than 10ug / ml, the difference between the cmc measurement value and the value measured by the surface tension method is small; and as the probe working concentration continues to increase, when the CUR working concentration exceeds 20ug / ml, the cmc measurement value results have a large deviation. The reason may be that when the probe concentration is too high, the fluorescence quenching caused by probe aggregation occurs at the inflection point corresponding to the just-formed micelle in the original curve. In addition, the second platform area after the rising area cannot be observed within the original concentration range, resulting in a significantly larger cmc measurement result.

[0246] The inventors speculate that the mechanism is as follows: CUR is a hydrophobic ACQ molecule, and it can only emit fluorescence when it is dissolved in a good solvent; when the CUR working concentration is low, CUR enters the micelle in a single molecule state and dissolves to emit fluorescence, and as the CUR working concentration increases, the proportion of CUR single molecules entering the micelle is low, while the proportion of CUR aggregate molecules entering the micelle is high, resulting in the fluorescence at the cmc value concentration being unclear. Only when the number of micelle molecules further increases, more CUR molecules can be detected after entering the micelle in a single molecule form. Therefore, too high a working concentration of CUR will lead to an increase in the measured cmc value.

[0247] Based on the comparative measurement results of the surface tension method and the fluorescence spectroscopy method, it can be known that for the detergent solution or washing water as the target test liquid, the working concentration of the probe used can be selected to be 0.04ug / ml or more, but not more than 20ug / ml, preferably not more than 10ug / ml. Therefore, the preferred range of the probe working concentration is 0.04-10ug / ml, more preferably 0.4-6ug / ml, and particularly preferably 0.8-4ug / ml.

[0248] The ACQ fluorescent probe composition of the present invention can be stored for a long time as a stable probe solution. After adding the sample to be tested, the cmc can be accurately measured without volatilizing the solvent, reducing the step of waiting for the organic solvent to evaporate, greatly improving the ease of use in actual scenarios, and can meet the actual needs of ACQ fluorescent probes in application fields such as cmc determination of surfactant solutions.

[0249] (Method for measuring cmc of surfactant solution)

[0250] The ACQ fluorescent probe composition of the present invention can be directly used in the form of a stable solution to measure the cmc concentration of a surfactant solution.

[0251] The method for measuring the cmc of a surfactant solution of the present invention comprises the following steps:

[0252] Preparation steps: Prepare a series of surfactant solutions at different concentrations.

[0253] Probe adding step: adding a certain amount of probe solution to the surfactant solution,

[0254] Detection steps: Use the detection mechanism to detect the fluorescence response value of each surfactant solution, and

[0255] Determining step: drawing a fluorescence response value-concentration curve according to the result obtained in the detection step, wherein the fluorescence response value-concentration curve has at least a first platform area and a rising area, and determining the concentration corresponding to the inflection point where the fluorescence response value changes from the first platform area to the rising area as the cmc of the surfactant solution,

[0256] Characterized in that the probe solution is the ACQ fluorescent probe composition of the present invention.

[0257] In the fluorescence response value-concentration curve obtained by the determination step, in which the abscissa is the concentration and the ordinate is the fluorescence intensity or voltage value, the detergent solution added with the ACQ fluorescent probe composition of the present invention usually does not fluoresce or the fluorescence intensity is very weak within a lower concentration range, and is maintained in a stable platform area (also called the first platform area), indicating that the ACQ probe molecules are in a state of aggregation with each other in the aqueous system, and therefore do not emit light or emit low fluorescence; as the detergent concentration increases to a specific value (cmc), the fluorescence intensity begins to increase significantly, indicating that at this time, the micelles of the detergent begin to form, and the ACQ probe molecules are transferred from the aqueous solution to the hydrophobic core of the micelles. Due to the good solvent environment, the probe molecules can exist in a single form, thereby emitting fluorescence. As the number of micelles increases, the fluorescence intensity of the probe also increases continuously, and the fluorescence curve rises rapidly; when all the fluorescent probe molecules exist in the form of single molecules in the micelles or surfactant aggregates, the fluorescence intensity tends to be stable again (second platform area).

[0258] In the fluorescence response value-concentration curve, the second platform area after the rising area is not necessarily present, and it is related to the relative relationship between the number of fluorescent probe molecules and the number of micelles, but the concentration corresponding to the inflection point between the platform area (first platform area) before the rising area and the rising area must be the concentration (i.e., cmc) at which micelles just begin to form. Therefore, when the inflection point of the change from the platform area to the rising area of ​​the above-mentioned fluorescence response value (such as fluorescence intensity or voltage value) can be detected by the detector and transmitted to the decision mechanism, the concentration corresponding to the inflection point can be determined by the decision mechanism as the cmc measurement value.

[0259] The inflection point of the change in the fluorescence response value can be determined by the fitting straight line intersection method and the inflection point judgment method. The fitting straight line intersection method is to find the intersection of the fitting straight line in the platform area and the fitting straight line in the rising area in the obtained fluorescence response value-concentration curve, and set the concentration of the detergent solution corresponding to the intersection as cmc (see Figure 2 ); The inflection point judgment method is to compare the change trend of the fluorescence intensity at the two data points before and after in the obtained fluorescence response value-concentration curve, and directly determine the inflection point according to the phenomenon that the change of the fluorescence intensity at the latter data point is significantly greater than that at the previous data point, and the concentration of the detergent solution corresponding to the inflection point is set as cmc (see Figure 3 ).

[0260] It is relatively simple to determine cmc by the inflection point judgment method, but the accuracy of cmc value determination is related to the setting interval of the measured concentration. When the concentration interval is too large (fewer data points for measuring the concentration), the accuracy decreases and the error is large; while the fitting straight line intersection method combines multiple sets of data to draw a fitting straight line and find the intersection point, and the stability and accuracy of cmc determination are higher. Therefore, it is preferred to use the fitting straight line intersection method to determine cmc.

[0261] The surfactant solution of the present invention comprises at least one of anionic surfactants, nonionic surfactants, cationic surfactants and amphoteric surfactants. More preferably, the surfactant comprises at least anionic surfactants and / or nonionic surfactants.

[0262] Examples of the anionic surfactant include surfactants such as alkyl carboxylate type, alkyl sulfate type, alkyl sulfonate type, alkyl ether sulfate ester salt, and phosphate type.

[0263] Examples of the nonionic surfactant include alkyl glucoside, alkyl alcohol ether glucoside, polyoxyethylene alkyl ether, polyoxyethylene polyoxypropylene alkyl ether, alkyl amine oxide, alkyl amide propyl amine oxide, and fatty acid alkanolamide.

[0264] The above-mentioned surfactants may be used alone or in combination of two or more. In addition, the surfactant solution may further contain a fluorescent whitening agent or the like.

[0265] In addition, the detection mechanism used in the present invention includes an existing fluorescence spectrophotometer and a fluorescence photodetector (abbreviated as CD detector) customized for the spectral characteristics of a specific ACQ molecule. The excitation wavelength of the fluorescence spectrophotometer can be set to any wavelength within the fluorescence excitation peak wavelength range corresponding to the probe molecule, and the emission wavelength can be selected to be any wavelength within the fluorescence emission peak wavelength range. Based on the fluorescence intensity or the voltage response value curve of the fluorescence, the cmc of the detergent can be determined.

[0266] The difference between the customized fluorescence photoelectric detector and the existing fluorescence spectrophotometer lies in the cost, accuracy, size, speed and modularity. The fluorescence spectrophotometer has high accuracy and can distinguish red / blue shift, but the cost is high, the instrument is relatively large, and the applicability is poor; while the customized detector can only detect the target wavelength and cannot distinguish red / blue shift, but it is small in size, has a fast detection rate, is modular, and has strong applicability.

[0267] In this specification, the “fluorescence response value” in the fluorescence response value-concentration curve refers to the fluorescence intensity when the measurement is performed using a fluorescence spectrophotometer, and refers to the voltage value when the measurement is performed using a CD detector.

[0268] The fluorescence photodetector used in the present invention includes any one of the following:

[0269] 1) Including excitation filter (430nm), dichroic mirror, emission filter (495nm), light source: peak wavelength 430nm, band 420-440nm, working current: 0.02A, working voltage: 5V, the detector acceptable wavelength range includes at least 480-510nm;

[0270] 2) Including excitation filter (550nm), dichroic mirror, emission filter (638nm), light source: peak wavelength 550nm, band 540-560nm, working current: 0.02A, working voltage: 5V, the detector acceptable wavelength range includes at least 620-650nm.

[0271] The above-mentioned fluorescence photodetector is customized for the fluorescence spectrum characteristics of the ACQ probe molecule of the present invention. Specifically, corresponding to the two ACQ molecules of CUR and NR, the test results show that both CD detectors have good responsiveness and sensitivity.

[0272] In addition, in the present invention, the steps of preparing the probe composition, the detergent solution to be tested, the preparation of washing water, adding the probe, fluorescence detection, and judging the cmc value can all be achieved based on high-precision metering equipment (sensors, peristaltic pumps, solenoid valves) and automated control.

[0273] For example: the probe composition mother liquor can be pre-configured by an electronic balance and a volumetric flask, or after the probe is quantitatively weighed using a pressure sensor, the solvent can be pumped in by a peristaltic pump to prepare a probe composition mother liquor of 0.001mg / ml-100mg / ml; different concentrations of detergent solutions / washing water to be tested can be prepared by pumping in different amounts of detergent and water using a peristaltic pump; corresponding doses of the detergent solution / washing water to be tested and the probe composition mother liquor can be respectively transferred using a peristaltic pump for mixing, and the amount of organic solvent added to the washing water to be tested is controlled not to exceed 10%, and the working concentration of the probe is controlled not to exceed 20uM; a photoelectric sensor can be used to detect changes in the fluorescence response value, and the measurement can be automatically judged and controlled based on the response value result, and finally the cmc value measurement result of the detergent can be output.

[0274] In addition, for the qualitative judgment of cmc, convenience can be improved. For example, when the cmc determination method of the present invention is used to qualitatively determine whether the detergent in the liquid to be tested has reached the cmc value, the threshold corresponding to the cmc value (threshold concentration ≥ cmc value concentration) can be set based on the measured data. When the measurement result is lower than the threshold, it is determined that the cmc value has not been reached. When the measurement result is greater than or equal to the threshold, it is determined that the cmc value has been reached or exceeded. When used in the washing industry, the setting of the threshold can be set according to the purpose of washing, the required detergent concentration, and the specific washing scene.

[0275] (Stain cleaning concentration determination method)

[0276] In the laundry industry, the standard for setting the amount of detergent is not only related to the cost-effectiveness of the detergent, i.e., the cleaning efficiency, but also to the degree of stain removal, i.e., the cleaning effect. According to a large number of studies conducted by the inventors, different concentrations of detergent are required to remove different stains. In this specification, the minimum concentration required to remove clothes with different stains is referred to as the "stain removal threshold concentration C". t ” (sometimes referred to as “cleaning threshold concentration C t " or "threshold concentration C t ”), and the fluorescence response value corresponding to the threshold concentration is called the “stain cleaning response threshold S0” (sometimes referred to as “cleaning response threshold S0” or “response threshold S0”). Usually, the stain cleaning threshold concentration C t ≥Critical micelle concentration (cmc) of wash water.

[0277] Stains are generally divided into three categories according to the washing principles: oil stains, color stains, and invisible stains; oil stains include but are not limited to collar stains, food oil stains, cosmetic oil stains and other stains with animal and plant fats or mineral oils as the main components; color stains include but are not limited to blood stains, fruit stains, aging yellowing stains, pigment stains, dye stains and other colored stains; invisible stains include milk stains, saliva stains, rice porridge stains and other stains that are not easily visible to the naked eye, usually protein stains and starch stains.

[0278] In the present invention, different stain cleaning threshold concentrations C can be set for the three types of stains, namely, oil stains, color stains and invisible stains. t In the case of actual machine washing, when it is detected that the concentration of detergent put into the washing water has reached or exceeded the above-mentioned stain cleaning threshold concentration, it is considered that the washing water at this concentration can clean the stained clothes, and the detergent concentration at this time can be determined as the "stain cleaning concentration".

[0279] Therefore, in the stain cleaning concentration determination method of the present invention, whether the detected concentration of the washing water reaches or exceeds the preset cleaning threshold concentration corresponding to different stains can be used to determine whether the washing water at the concentration can clean the clothes. The preset cleaning threshold concentration is ≥ cmc.

[0280] The stain cleaning concentration determination method of the present invention comprises the following steps:

[0281] Liquid preparation step: adding a first predetermined amount of detergent into a washing device containing a predetermined amount of water and clothes, stirring and mixing to obtain washing water,

[0282] Sampling step: sampling from the washing water and adding a small amount of probe solution to obtain the washing water to be tested.

[0283] Detection step: using a detection mechanism to detect the fluorescence response value S of the washing water to be tested,

[0284] Determination step: judging whether the detergent concentration of the washing water to be tested is a stain cleaning concentration according to whether the detected fluorescence response value S reaches or exceeds a preset cleaning response threshold value S0; if it does not reach the preset cleaning response threshold value S0, the determination result is "no"; if it reaches or exceeds the preset cleaning response threshold value S0, the determination result is "yes", and

[0285] Control step: Based on the determination result of the determination step, control the number of times the detergent is added in the liquid preparation step; if the determination result is "no", continue to add a second predetermined amount of detergent in the liquid preparation step, and then perform subsequent sampling steps, detection steps and determination steps; if the determination result is "yes", stop adding the detergent, output the determination result, or start the washing device to continue washing.

[0286] Wherein, the probe solution may adopt the ACQ fluorescent probe composition of the present invention.

[0287] The preset washing response threshold S0 in the above determination step may be a fluorescence response value corresponding to the cmc of the washing water, or may be a washing threshold concentration C of the washing water. t The corresponding fluorescence response value.

[0288] The cmc of washing water can be measured in advance by the cmc measurement method of the present invention, or in the stain cleaning concentration determination method of the present invention, the liquid preparation step to the measurement step can be repeated multiple times, and a fluorescence response value-concentration curve can be drawn based on the results obtained in the detection step, and the concentration corresponding to the inflection point where the fluorescence response value changes is determined as the cmc.

[0289] The stain cleaning threshold concentration Ct can be determined by the actual machine washing effect, that is, by using a series of detergent concentrations of washing water to actually machine wash the stained clothes, the lowest concentration that is confirmed to have a good cleaning effect is determined as the stain cleaning threshold concentration. In addition, after measuring the cmc of the detergent solution, the stain cleaning threshold concentration Ct can be set to a fixed value greater than or equal to the cmc concentration.

[0290] In the present invention, a fluorescence response value-concentration curve is drawn according to the detection results in the detection step, and the curve generally includes two platform areas and a rising area between the two. Taking into account the washing effect and the cost performance of the detergent, the stain cleaning threshold concentration Ct is preferably set within the range of the rising area in the curve, that is, it is preferred to select any value between the two platform areas and the inflection point of the rising area to set the cleaning threshold concentration Ct as needed.

[0291] The setting of the stain cleaning threshold concentration Ct can be considered in terms of washing purpose, load / stain (clothing load, stain type, stain amount, etc.), scene (household washing machine, industrial washing equipment, etc.) and the like according to the requirements of different scenes. When applied to the detergent delivery control method of washing equipment, the amount of detergent required during the washing process is related to the load of the washed fabric and the type and degree of dirt; when the load in the washing equipment is large, the stains are many and complex, a higher threshold value can be considered (for example, the fluorescence response threshold value of the fluorescent photodetector can be set to 0.22, corresponding to a detergent cleaning threshold concentration of about 0.45 g / L) to improve the cleaning rate of the clothes; when the load in the washing equipment is small, the stains are few and simple, a conventional threshold value can be considered (the fluorescence response threshold value of the fluorescent photodetector can be set to 0.15, corresponding to a cleaning threshold concentration of about 0.35 g / L), so that the amount of detergent can be saved while ensuring the washing effect, so as to obtain the highest cost-effectiveness of detergent addition.

[0292] Considering that the cmc values ​​of various detergents in different scenarios may vary and are not a constant value, the stain cleaning threshold concentration Ct can be determined based on cmc and the cleaning coefficient a (a unitless coefficient), that is, the stain cleaning threshold concentration Ct is determined by the following formula 3:

[0293] Ct=cmc×(1+a) (Formula 3)

[0294] In Formula 3, cmc is the measured cmc of washing water, and a is the cleaning coefficient, ranging from 0≤a≤10, preferably 0.1≤a≤5, and more preferably 0.15≤a≤3.5. a may take different values ​​corresponding to different types and degrees of dirtiness of stains.

[0295] In addition, the preset cleaning response threshold S0 in the above determination step may also be based on the maximum response value of the fluorescence intensity (S max ) or fluorescence increment (S max -S blank ), wherein the detergent concentration corresponding to the response value of the set percentage or increment percentage is still greater than or equal to the cmc concentration. In this specification, the percentage of the maximum response value of the fluorescence intensity or the percentage of the fluorescence increment is called the threshold percentage β, and the unit is 100%.

[0296] For example: in industrial and household scenarios, the relationship between the cleaning rate of common oil stains, color stains, invisible stains, etc., the amount of detergent used, and the detection value (voltage value) of the customized fluorescent photoelectric detector is measured, and the threshold percentage (β) can be arbitrarily set within the range of 0<β<1 (i.e., the range of 0 to 100%, but excluding the endpoint value). Considering that industrial washing scenarios involve more pretreatment processes such as pre-coating and color stain soaking before washing, β can be set lower, for example, 0.35, that is, the cleaning response threshold S0 can be set to 0.35×S max In the household washing scenario, there is usually no pretreatment or the treatment method is relatively simple, and the mechanical force of the household washing machine is smaller than that of the industrial washing machine. That is, the household scenario requires a higher detergent concentration than the industrial scenario to achieve a similar washing effect. β can be set higher, for example, 0.55, that is, the washing response threshold S0 can be set to 0.55×S max Alternatively, the increment of the cleaning response threshold S0 can be set to 0.2×(S max -S blank ), the threshold in the home scenario is 0.4×(S max -S blank ).

[0297] That is, the wash response threshold S0 is determined by the following formula 4 or formula 5:

[0298] S0=β×Smax (Formula 4)

[0299] S0=S blank +β×(S max -S blank ) (Formula 5)

[0300] In the formula, S max is the maximum fluorescence intensity or maximum voltage response value of the washing water, or the second platform value in the fluorescence response value-concentration curve diagram, S blank is the background fluorescence intensity of washing water or the minimum voltage response value, or the first platform value in the fluorescence response value-concentration curve diagram, β is the threshold percentage, the unit is 100%, and the range is 0<β<1. Corresponding to different types and degrees of dirtiness of stains and different washing application scenarios, β can take different values, preferably 0.1≤β≤0.9, and more preferably 0.2≤β≤0.8.

[0301] In the stain cleaning concentration determination method of the present invention, regarding the amount of detergent added, the above-mentioned "first predetermined amount" and "second predetermined amount" can be set as needed. In addition, regarding the amount of water, the amount of clothes, the sampling amount of washing water and the amount of probe solution added, there are no special regulations and they can be appropriately set according to the needs of the actual use scenario and the preferred range of the probe working concentration.

[0302] The ACQ fluorescent probe composition of the present invention is particularly suitable for determining whether the clothes are clean by comparing the real-time concentration of the detergent with the stain cleaning threshold concentration. The reason is that: by comparing the difference between the fluorescence response value-concentration curve of the ACQ probe and the AIE probe, it can be seen that in the curve obtained by using the ACQ fluorescent probe composition, the first inflection point from the platform area to the rising area is cmc. After exceeding cmc, its fluorescence response gradually increases until the second platform area, which is very suitable for monitoring concentrations greater than cmc (see Figure 2 ); In contrast, in the fluorescence response value-concentration curve obtained using the AIE fluorescent probe composition (e.g., HPS), only the highest point of the curve corresponds to cmc, and the ordinate value (fluorescence intensity or voltage) below the highest point may correspond to two concentration values ​​on the abscissa, so it is impossible to accurately monitor concentrations greater than cmc. In addition, in the curve obtained using the ACQ fluorescent probe composition, there is a relatively gentle change interval between the platform areas, which is convenient for adjusting the set value of the stain cleaning threshold concentration.

[0303] Since the curve obtained by the ACQ probe molecule is more suitable for determining the stain cleaning concentration and adjusting the stain cleaning threshold concentration, the ACQ fluorescent probe composition of the present invention is more advantageous than the AIE fluorescent probe composition in controlling the automatic addition of detergent by setting and adjusting the stain cleaning threshold concentration.

[0304] (Detergent dispensing control method)

[0305] One practical application field of the ACQ fluorescent probe composition of the present invention is the control of the dosage of detergent in automatic washing equipment.

[0306] In the detergent dosing control of automatic washing equipment, the amount of detergent added during the washing process is related to the amount of water, the load of the washed fabric, and the type and degree of dirt. The present invention can add detergent in a multiple quantitative dosing manner, and automatically determine the required dosing amount by measuring whether the surfactant concentration of the washing water solution is above the cmc, or whether it is above the cleaning threshold concentration. The present invention can provide a detergent dosing control method, characterized in that it includes:

[0307] Liquid preparation step: in the washing device, a first predetermined amount of the detergent is added into the inner barrel according to the weight of the laundry and the amount of water inlet, and mixed with the water in the inner barrel to obtain washing water or detergent solution;

[0308] Sampling step: collecting a predetermined amount of the washing water or detergent solution from the inner barrel as a sample;

[0309] Liquid collection step: Take out a small amount of probe solution and add it to the sample.

[0310] Mixing step: mixing the sample and the probe solution to obtain a test solution;

[0311] Detection step: detecting the fluorescence response value of the test liquid and outputting a detection signal S;

[0312] Determination step: receiving the detection signal S, and determining whether the detergent concentration of the test liquid reaches the critical micelle concentration or the preset cleaning threshold concentration according to whether the detection signal S reaches or exceeds the preset response threshold S0, wherein the cleaning threshold concentration is greater than or equal to the critical micelle concentration; and

[0313] Control step: Based on the judgment result of the judgment step, control the subsequent addition of the detergent, wherein if the judgment result is that the critical micelle concentration or the preset cleaning threshold concentration has not been reached, continue to add the second predetermined amount of the detergent into the inner barrel in the liquid preparation step; if the judgment result is that the critical micelle concentration or the preset cleaning threshold concentration has been reached, stop adding the detergent.

[0314] Wherein, the probe solution may adopt the ACQ fluorescent probe composition of the present invention.

[0315] In order to realize the judgment of detergent dosage control, it is necessary to output the fluorescence intensity F of the washing water detected by the fluorescence detector in the detection step as a detection signal S, and the detection signal S is a voltage signal corresponding to the fluorescence intensity F of the washing water at a specific wavelength. The detection signal S is output to the judgment step and control step described later.

[0316] A series of test solutions with increasing concentrations of detergents can be prepared in advance in multiple sample pools or a single sample pool, or washing water can be directly sampled from the inner barrel of the washing equipment into the sample pool in real time when the equipment is running and washing is in progress. Through the cmc determination method of the surfactant solution of the present invention, the detection signal corresponding to the inflection point where the platform area of ​​the detected curve changes into the rising area is set as the response threshold S0 corresponding to the critical micelle concentration cmc, or a specific stain cleaning threshold concentration Ct is selected in the platform area of ​​the curve according to the situation, and the detection signal corresponding to the stain cleaning threshold concentration Ct is set to the response threshold S0 (sometimes also called St) corresponding to the cleaning threshold concentration Ct, wherein the stain cleaning threshold concentration Ct is greater than or equal to the critical micelle concentration cmc.

[0317] Then, in the above judgment step, if the detection signal S is equal to or higher than the preset response threshold S0, the judgment result is yes (the detergent concentration C has reached the cmc or the washing threshold concentration Ct), and the further addition of detergent is stopped at this time; if the detection signal S is lower than the preset response threshold S0, the judgment result is no (the detergent concentration C has not yet reached the cmc or the washing threshold concentration Ct), then return to the liquid preparation step and continue to add detergent.

[0318] The cmc concentration of washing water actually used in washing equipment is affected by many factors (such as fabric type, quantity, amount of dirt, water temperature, etc.). From the analysis of Gibbs free energy data, surfactants are preferentially adsorbed at the gas-liquid, liquid-liquid and solid-liquid interfaces (fabric, dirt), and then form aggregates (such as micelles) in the solution. The surfactants in the washing water of actual machine washing will preferentially adsorb to the gas-liquid, solid-liquid and liquid-liquid interfaces before forming micelles in the washing water, which consumes part of the surfactant, resulting in the cmc of the washing water being greater than the cmc of the detergent solution. This is understandable. It is based on this principle of action that we use online monitoring to determine whether the detergent concentration in the washing water reaches the cmc or is above the cleaning threshold concentration as the basis for automatic detergent addition.

[0319] In the washing water of actual machine washing, the detection signal S corresponding to the inflection point value when the platform area of ​​the detected curve changes to the rising area can also be set as the critical micelle concentration value S0, and the detection signal S corresponding to the judgment that the stain can be washed can be set as the washing response threshold St. The surfactant concentration (washing threshold concentration Ct) corresponding to the washing response threshold St is usually greater than the critical micelle concentration cmc.

[0320] During actual machine washing, the washing response threshold St can be preset. First, a certain amount of detergent is added, and the fluorescence response value of the washing water is monitored to see whether it reaches the washing response threshold St. If not, continue to add detergent and continue to monitor whether the fluorescence response value of the washing water reaches the washing response threshold St. If it has reached or exceeded the washing response threshold St, stop adding detergent.

[0321] In addition, a maximum number of additions may be set during actual machine washing to avoid excessive addition of detergent due to a detector failure.

[0322] Therefore, it is preferred that the control step also includes a number limiting step: a number threshold representing the maximum number of times the detergent is added is pre-set, and if after the detergent has been added more than once, although the judgment result is still that the critical micelle concentration or the preset cleaning threshold concentration has not been reached, the number of times the detergent has been added has reached the number threshold, then stop adding the detergent in the liquid preparation step.

[0323] Specifically, the detergent dosage control of the present invention can be carried out in the following two methods.

[0324] (Method 1) Determine whether the washing water concentration is above the cmc by online monitoring

[0325] In industrial washing machines, when the concentration of Supreme Biotech laundry detergent reaches cmc, the overall detergency reaches or approaches the platform position of detergency. As shown in Table 9, the cmc concentration of Supreme washing water in actual machine washing reaches at least 0.3 (± 0.01) g / L, which is significantly higher than the cmc of the directly prepared detergent solution. Therefore, in actual machine washing, the detergent is temporarily added in multiple times and equal amounts, and it is preferred that the concentration of the corresponding washing water at the second to last addition is consistent with the cmc.

[0326] Table 9. cmc of Supreme Laundry Detergent and Supreme Washing Water Solution

[0327] Supreme Solution Type Test Method Test Results Direct solution preparation Surface tension method 0.067g / L Fluorescence detection 0.100g / L Actual machine washing water Surface tension method 0.3g / L Fluorescence detection 0.3g / L

[0328] (Method 2) Determine whether the concentration of washing water is above the stain cleaning threshold concentration by online monitoring

[0329] The decision logic is to determine whether the measured concentration of the washing water is greater than the stain cleaning threshold concentration. If it is greater than or equal to the threshold concentration, it means that the cleaning point has been reached.

[0330] A 5kg simple stained fabric load is added to the industrial washing machine. At this time, the fluorescence response threshold corresponding to the reference stain cleaning threshold concentration Ct can be 0.15. In the actual washing scenario shown in Table 10, the preferred detergent application is 1 time. At this time, the stain is cleaned and the amount of detergent and water used are both small. At the end of the application, the fluorescence response value is 0.161V, and the detergent concentration is 0.41g / L, which is 37% higher than the cmc measured value of 0.3g / L during actual machine washing (i.e., the cleaning coefficient a=0.37) (see Table 10).

[0331] Table 10. Example of loading under 5 kg load in industrial washing machine

[0332]

[0333] (Detergent dispensing control system)

[0334] The present invention also provides a detergent dispensing control system, which is used to automatically control the amount of detergent dispensed in a washing device, wherein the washing device comprises: an inner barrel for placing laundry and water to be washed; a storage device for storing detergent; and a dispensing device for dispensing a first predetermined amount of the detergent into the inner barrel, mixing and stirring with the water in the inner barrel to obtain washing water or a detergent solution, characterized in that:

[0335] The detergent delivery control system comprises:

[0336] A liquid storage device, used for storing a probe solution;

[0337] a sampling device for collecting a predetermined amount of the washing water or detergent solution from the inner tub as a sample;

[0338] A liquid taking device, used for taking out a small amount of probe solution from the liquid storage device and adding it to the sample;

[0339] Mixing device: used for mixing the sample and the probe solution to obtain a test solution;

[0340] A detection device, used to detect the fluorescence response value of the test liquid and output a detection signal S;

[0341] A judging device: used for receiving the detection signal S, and judging whether the detergent concentration of the test liquid reaches the critical micelle concentration cmc or the preset cleaning threshold concentration Ct according to whether the detection signal S reaches or exceeds the preset response threshold S0, wherein the cleaning threshold concentration Ct is greater than or equal to the critical micelle concentration cmc;

[0342] a CMC determination device, for, under the condition that there is no laundry in the inner barrel, using the dispensing device to dispense a predetermined amount of the detergent into the inner barrel in batches, and using the liquid storage device, the sampling device, the liquid taking device, the mixing device and the detection device to repeatedly perform multiple groups of measurements, and determining the critical micelle concentration of the detergent solution according to a plurality of detection data corresponding to different detergent concentrations output by the detection device; and

[0343] a control device, for controlling the subsequent delivery of the detergent by the delivery device of the washing device based on the determination result of the determination device,

[0344] Wherein, if the judgment result of the judgment device is that the critical micelle concentration cmc or the preset cleaning threshold concentration Ct has not been reached, the control device controls the dispensing device to continue to dispense the second predetermined amount of the detergent into the inner barrel of the washing device; if the judgment result of the judgment device is that the critical micelle concentration cmc or the preset cleaning threshold concentration Ct has been reached or exceeded, the control device controls the dispensing device to stop dispensing the detergent;

[0345] Wherein, the probe solution may adopt the ACQ fluorescent probe composition of the present invention.

[0346] In one embodiment of the detergent dispensing control system of the present invention, the control device may control the subsequent dispensing of the detergent by the dispensing device of the washing machine based on the determination result of the determination device.

[0347] The cleaning response threshold S0 is a fluorescence response value corresponding to the critical micelle concentration cmc of the detergent solution, or a fluorescence response value corresponding to the stain cleaning threshold concentration Ct.

[0348] The critical micelle concentration cmc is the critical micelle concentration of the detergent solution measured in advance, or the critical micelle concentration of the detergent solution or the washing water determined by online measurement by the cmc determination device, and the cleaning threshold concentration Ct is calculated using the following formula 3:

[0349] Ct=cmc×(1+a) (Formula 3)

[0350] Where a is the cleaning coefficient, ranging from 0≤a≤10. Depending on the type and degree of dirtiness of stains, a can take different values.

[0351] Alternatively, the washing response threshold S0 is determined by the following formula 4 or the following formula 5:

[0352] S0=β×S max (Formula 4)

[0353] S0=S blank +β×(Smax -S blank ) (Formula 5)

[0354] In the formula, S max is the maximum fluorescence intensity or the maximum voltage response value of the washing water, or the second platform value in the fluorescence response value-concentration curve of the washing water; S blank is the background fluorescence intensity or minimum voltage response value of the washing water, or the first platform value in the fluorescence response value-concentration curve of the washing water; β is the threshold percentage, the unit is 100%, and the range is 0<β<1. Corresponding to different types and degrees of dirtiness of stains, β can take different values.

[0355] Preferably, a number threshold indicating the maximum number of times the detergent is dispensed is also set in the control device. If, after the dispensing device has dispensed the detergent more than once, although the judgment result is that the critical micelle concentration or the preset cleaning threshold concentration has not been reached, the number of times the detergent has been dispensed has reached the preset number threshold, the control device controls the dispensing device to stop dispensing the detergent.

[0356] Example

[0357] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples unless it departs from the gist of the present invention.

[0358] (Example 1)

[0359] The CUR-DGME probe combination was used to detect the cmc value of Supreme Biotech (Bright White) detergent solution.

[0360] <1> Preparation of CUR-DGME fluorescent probe composition:

[0361] Accurately weigh the CUR probe into a clean beaker, add DGME and transfer the solution to a volumetric flask to make up to volume, so that the final CUR-DGME probe composition stock solution concentration is 1 mg / ml.

[0362] <2> Preparation of the detergent solution to be tested:

[0363] Use the weighing method or gradient dilution method to prepare Supreme Biotech (Bright Whitening) detergent (production batch number AHA20260206, referred to as ZZLB) into a series of detergent solutions at concentrations including 0.02g / L, 0.05g / L, 0.1g / L, 0.2g / L, 0.5g / L, 1g / L, 2g / L, 10g / L, and 20g / L.

[0364] <3> Addition and treatment of probe composition:

[0365] Use a pipette to accurately transfer 40 uL of the CUR-DGME probe composition into 10 mL of the detergent solution to be tested, so that the working concentration of the probe in the detergent solution to be tested is 4 ug / mL (ignoring slight volume changes).

[0366] <4> Fluorescence intensity detection:

[0367] The spectral parameters of the fluorescence spectrophotometer were set as follows: excitation wavelength Ex = 430 nm, slit width 5 nm, scanning speed 1200 nm / min, emission wavelength scanning range 440-700 nm, and 2 mL of the mixed detergent solution containing the probe was accurately transferred to the fluorescence cuvette. The fluorescence emission of solutions with different detergent concentrations was measured using a fluorescence spectrophotometer. The scanning results are shown in Figure 2. Figure 1 shown.

[0368] <5> Determination of cmc value:

[0369] Reference Figure 1 The results shown in FIG. 1 are as follows. The peak height data at the maximum emission wavelength Em = 495 nm is selected as the fluorescence response value of the target detergent solution to be tested. The fluorescence response value is used to plot the value relative to the detergent concentration. The results are as follows Figure 2 Based on Figure 2 The fluorescence response value (fluorescence intensity)-detergent concentration curve is obtained, and the fitting straight line of the platform area and the fitting straight line of the rising area are obtained respectively. The concentration coordinate corresponding to the intersection of the fitting straight line and the fitting straight line is the cmc value of the detergent.

[0370] from Figure 2 It can be seen that the cmc of the directly prepared Supreme Biotechnology (Bright Whitening) detergent solution is about 0.1g / L.

[0371] (Example 2)

[0372] The NR-NMP composition was used to detect the cmc value of Supreme Biotechnology (Bright White) washing water.

[0373] <1> Preparation of NR-NMP fluorescent probe composition:

[0374] Accurately weigh the NR probe into a clean beaker, add NMP to dissolve it directly, and transfer the solution to a volumetric flask to make up the volume, so that the final concentration of the mother solution of the NR-NMP probe composition is 1 mM.

[0375] <2> Preparation of washing water to be tested:

[0376] The preparation parameters of Supreme Biotechnology (Bright Whitening) washing water are: Supreme Biotechnology (Bright Whitening) detergent (production batch number is AHA20260206) + 12 kinds of dirty cloth (carbon black, clay, egg white, whole egg, blood stains, sebum, vegetable oil, lipstick, butter, rice starch, etc.) + 2.5kg clothing load, the water quality is 250ppm hard water, the washing equipment is a drum washing machine, and the pre-water volume is 13L.

[0377] Using the same dirty cloth, clothing load, water quality and the same washing equipment, by adding different amounts of Supreme Biotech (Bright White) detergent, wash water containing different detergent concentrations was prepared. The converted concentrations include 0.025g / L, 0.075g / L, 0.15g / L, 0.3g / L, 0.6g / L, 0.9g / L, 1.2g / L, 1.5g / L, 1.8g / L, and 2.4g / L.

[0378] <3> Addition and treatment of probe composition:

[0379] Use a pipette to accurately transfer 20uL of NR-NMP probe stock solution to 10mL of the washing water to be tested, so that the working concentration of the probe in the washing water to be tested is 2uM (without considering slight volume changes).

[0380] <4> Fluorescence intensity detection:

[0381] 10 ml of the washing water to be tested containing the probe was transferred to a glass sample bottle, and the fluorescence response value (voltage value) of the washing water under different detergent concentrations was measured using a customized fluorescence photodetector (including excitation filter (550 nm), dichroic mirror, emission filter (638 nm), light source: peak wavelength 550 nm, band 540-560 nm, working current: 0.02 A, working voltage: 5 V).

[0382] <5> Determination of cmc value:

[0383] Based on the results from the custom-made fluorescence photodetector, the fluorescence response was plotted against the wash water concentration. Figure 3 As shown, based on Figure 3 The fluorescence response value (voltage value)-detergent concentration curve can directly determine the cmc value corresponding to the detergent at the inflection point of the curve.

[0384] from Figure 3 It can be seen that the cmc value of Supreme Biotechnology (Bright White) washing water is about 0.3g / L.

[0385] (Example 3)

[0386] Referring to Example 1 or Example 2, a detergent solution of Supreme Biotech (Bright Whitening) to be tested was prepared, and the types of probes and adjuvants in the fluorescent probe composition were adjusted, wherein the probes were CUR and NR, and the adjuvants included BUT, EG, NMP and PEG200, and the detection was performed using a customized CD detector. The obtained fluorescence response value (voltage value)-detergent concentration curve is shown in the figure. Figure 4 Among them, due to the weak detection signal of NR-EG, Figure 4 The results are not shown in (B).

[0387] from Figure 4 It can be seen that by using various combinations of probes and auxiliary agents in the fluorescent probe composition of the present invention, the cmc value of the detergent solution can be determined based on the change curve of the characteristic emission peak in the obtained fluorescence response value (voltage value)-detergent concentration curve and using the fitting straight line intersection method or the inflection point judgment method. Among them, when NMP and PEG200 are used as auxiliary agents, the obtained curve graph has better consistency, indicating that the influence on the cmc determination result is smaller, and it is a more preferred auxiliary agent of the present invention.

[0388] (Example 4)

[0389] The detergent to be tested was adjusted to detergent solutions of other commercially available brands, including GB, LYL, AM, CN, WLS, LBJH, SGY, TZ, etc. The meanings of the abbreviations of each detergent are shown in Table 11.

[0390] The measurement was performed in the same manner as in Example 1 or Example 2 except that the type of detergent was changed to the detergent shown in Table 11. The measurement results are shown in Table 11 below.

[0391] Table 11

[0392]

[0393] Figure 5 It is a graph showing the CMC of the above-mentioned detergent solutions of various brands measured by the surface tension method.

[0394] Figure 6 The graph shows the fluorescence response value-detergent concentration curve when the cmc of the above-mentioned detergent solutions of various brands are measured using two ACQ fluorescent probe compositions respectively using a fluorescence spectrophotometer, (A) CUR probe composition; (B) NR probe composition.

[0395] From Table 11 and Figure 5 , Figure 6It can be seen that the probe composition of the present invention can be used to measure the cmc of various commercially available detergents by fluorescence spectroscopy, and the measurement results are basically consistent with the cmc results measured by conventional surface tension method, the error is within the allowable range, and does not affect actual use.

[0396] (Example 5)

[0397] The detergent solution to be tested was adjusted to a directly prepared detergent solution and washing water used in different machine washing scenarios (industrial machine washing or household washing machine washing), wherein some detergents contained fluorescent whitening agents. The two ACQ fluorescent probe compositions of the present invention, namely (A) CUR probe composition and (B) NR probe composition, were used to perform cmc measurement in the same manner as in Example 1 or Example 2. The obtained fluorescence response value-detergent concentration curve is shown in the figure. Figure 7 .

[0398] Depend on Figure 7 It can be seen that the probe composition of the present invention can be used to determine the cmc of detergent solutions or washing water in various usage scenarios by fluorescence spectroscopy, and the measurement results are basically consistent. The cmc concentration of actual machine washing washing water is greater than the cmc concentration of directly prepared detergent solutions, and the fluorescent whitening agent has little effect on the results and does not affect actual use.

[0399] (Example 6)

[0400] The detergent solution to be tested was adjusted to other commercially available products containing surfactant components, such as softener, oxygen bleach, disinfectant, etc., and the measurement was carried out in the same manner as in Example 1 or Example 2. The results showed that the cmc value of the detergent could be measured.

[0401] Figure 8 The graphs are fluorescence response values-detergent concentration curves obtained by using the fluorescent probe composition of the present invention to test the cmc of other types of products containing surfactant ingredients (softener, oxygen bleach, disinfectant), (A) CUR probe composition; (B) NR probe composition.

[0402] from Figure 8 It can be seen from the results that for other types of products with added surfactants, the fluorescent probe method using the fluorescent probe composition of the present invention can still measure the fluorescence intensity response value, and the cmc value obtained by the measurement has a strong correlation with the amount of surfactant added in the product, indicating that the fluorescent probe composition of the present invention has strong applicability.

[0403] In addition, from Figure 8 It can be seen that when the concentration of the softener is very high, the increase in the softener concentration will significantly reduce the clarity of the solution, which in turn leads to a decrease in the light transmittance of the solution. Therefore, the curve shows a downward trend after reaching the highest point.

[0404] (Example 7)

[0405] With reference to Examples 1 and 3, a Supreme Biotech (Bright Whitening) detergent solution was prepared, and a CUR probe composition (probe mother solution) with a probe concentration of 0.001 mg / ml was used, and the amount of the probe mother solution added was adjusted to 400 ul, or a NR probe composition with a probe concentration of 100 mg / ml was used, and the amount of the probe mother solution added was adjusted to 1 ul, so that the amount of organic solvent (auxiliary agent) added to the washing water to be tested and the probe working concentration both met the preferred range of the present invention (i.e., the solvent addition amount does not exceed 4%, and the probe working concentration does not exceed 10 ug / ml), and the CD detector was used for measurement in the above two cases respectively.

[0406] The results of the determination are shown in Table 12. The cmc results measured in the two cases are 0.061 g / l and 0.171 g / l, respectively. Both can achieve the determination of the cmc of Supreme Biotech (Bright White) detergent, and the measured values ​​are compared with the results (Reference Example 1 and Reference Example 2) under the conditions of the same probe working concentration in Table 8, and the errors are all within the allowable range. It can be seen that when the amount of probe solution added and the working concentration of the probe are within the range required by the present invention, the cmc value of the detergent can be determined, and its accuracy meets the requirements at the practical level.

[0407] Table 12

[0408]

[0409] (Example 8)

[0410] In order to achieve the miniaturization of washing equipment or detergent dosing control system, we customized the following fluorescence photodetector with the following specifications: 1) Including excitation filter (430nm), dichroic mirror, emission filter (495nm), light source: peak wavelength 430nm, band 420~440nm, working current: 0.02A, working voltage: 5V, the detector's acceptable wavelength range includes at least 480-510nm; 2) Including excitation filter (550nm), dichroic mirror, emission filter (638nm), light source: peak wavelength 550nm, band 540~560nm, working current: 0.02A, working voltage: 5V, the detector's acceptable wavelength range includes at least 620-650nm.

[0411] The CMC of the aqueous solution of Supreme Biotechnology (Bright White) laundry detergent was measured by using a fluorescence spectrophotometer and the above-mentioned customized fluorescence photodetector, respectively, with reference to Example 1 or Example 2. The results are shown in Table 13 below.

[0412] Table 13 Comparison of customized fluorescence photoelectric detection and fluorescence spectrum detection data

[0413]

[0414] *Since NR has poor solubility in ethylene glycol (poorly soluble), after adding it to the detergent solution to be tested, no effective fluorescence signal was detected using the customized fluorescence photodetector, so no results were obtained.

[0415] It can be seen from Table 13 that the test results of the customized fluorescence photodetector of the present invention are repeatable and highly accurate, and can be applied to miniaturized washing equipment.

[0416] Industrial Applicability

[0417] By adopting the ACQ fluorescent probe composition of the present invention, it can be stored for a long time in the form of a stable probe solution, and can be directly used for CMC determination of surfactant solutions and determination of stain cleaning concentration, especially in the control of detergent dosage in industrial water washing equipment, household washing machines, and household washer-dryers.

Claims

1. An ACQ fluorescent probe composition, characterized in that: It is a probe solution for directly determining the cmc concentration of surfactants, containing probe molecules and additives. The probe molecule is a fluorescent molecule with aggregation-induced luminescence quenching (ACQ) properties. The auxiliary agent comprises one or more non-volatile organic solvents, wherein the boiling point of the organic solvent is above 100° C. The distance between the probe molecule and the organic solvent, i.e., the HSP distance Ra, is 17 (MPa). 1 / 2 the following.

2. The ACQ fluorescent probe composition according to claim 1, wherein The Hansen solubility parameter (HSP) of the probe molecule is 15 (MPa) 1 / 2 ~35(MPa) 1 / 2 .

3. The ACQ fluorescent probe composition according to claim 1, wherein The solubility of the probe molecule in the auxiliary agent is classified as soluble or above.

4. The ACQ fluorescent probe composition according to any one of claims 1 to 3, wherein The difference Δδ between the Hansen solubility parameter of the auxiliary agent and the probe molecule is -3 (MPa) 1 / 2 ~+12(MPa) 1 / 2 .

5. The ACQ fluorescent probe composition according to any one of claims 1 to 3, wherein The viscosity of the auxiliary agent is less than 30 mPa·s.

6. The ACQ fluorescent probe composition according to any one of claims 1 to 3, wherein The additive is soluble in water and has a density of 0.9 g / cm 3 ~1.2g / cm 3 .

7. The ACQ fluorescent probe composition according to any one of claims 1 to 3, wherein The flash point of the auxiliary agent is above 60°C.

8. The ACQ fluorescent probe composition according to any one of claims 1 to 3, wherein The probe molecule is an ACQ molecule whose luminescence strategy is based on changes in fluorescence intensity or characteristic wavelength. It includes ACQ molecules with blue-shifted characteristic wavelength, ACQ molecules with red-shifted characteristic wavelength, and ACQ molecules with unchanged characteristic wavelength.

9. The ACQ fluorescent probe composition according to any one of claims 1 to 3, wherein The probe molecule is one or more ACQ molecules selected from the group consisting of curcumin (CUR), Nile red (NR), coumarin (C480), rhodamine B (RhB), N-phenyl-1-naphthylamine (NPN) and pyrene (PYR), The auxiliary agent contains one or more organic solvents selected from n-butanol, ethylene glycol, N-methylpyrrolidone (NMP), N-ethylpyrrolidone (NEP), dimethylformamide (DMF), diethylene glycol monoethyl ether (DGME), ethyl glycolate, polyethylene glycol 200 (PEG200), 1,3-butanediol and 1,5-pentanediol.

10. The ACQ fluorescent probe composition according to any one of claims 1 to 3, wherein The probe molecule is at least one ACQ molecule selected from curcumin (CUR), Nile red (NR) and coumarin (C480), The auxiliary agent comprises at least one organic solvent selected from the group consisting of N-methylpyrrolidone (NMP), N-ethylpyrrolidone (NEP), polyethylene glycol 200 (PEG200) and diethylene glycol monoethyl ether (DGME).

11. A method for measuring the cmc of a surfactant solution, characterized in that: The steps are as follows: Preparation steps: Prepare a series of surfactant solutions at different concentrations. Probe adding step: adding a certain amount of probe solution to the surfactant solution, Detection steps: Use the detection mechanism to detect the fluorescence response value of each surfactant solution, and Determining step: drawing a fluorescence response value-concentration curve according to the result obtained in the detection step, wherein the fluorescence response value-concentration curve has at least a first platform area and a rising area, and determining the concentration corresponding to the inflection point where the fluorescence response value changes from the first platform area to the rising area as the cmc of the surfactant solution, Wherein, the probe solution is the ACQ fluorescent probe composition according to any one of claims 1 to 10.

12. The cmc measurement method according to claim 11, wherein In the determination step, the concentration corresponding to the intersection of the fitting straight line of the first platform area and the fitting straight line of the rising area in the fluorescence response value-concentration curve diagram is determined as the cmc of the surfactant solution.

13. The cmc measurement method according to claim 11 or 12, wherein: Relative to 10 ml of the surfactant solution, the amount of solvent added to the probe solution does not exceed 400 μl, and the probe working concentration of the probe molecule does not exceed 10 ug / ml.

14. The cmc measurement method according to claim 11 or 12, wherein: The surfactant includes at least one of anionic surfactants, nonionic surfactants and amphoteric surfactants.

15. The cmc measurement method according to claim 11 or 12, wherein: The surfactant solution also contains a fluorescent whitening agent.

16. A method for determining stain cleaning concentration, characterized in that: The steps include: Liquid preparation step: adding a first predetermined amount of detergent into a washing device containing a predetermined amount of water and clothes, stirring and mixing to obtain washing water, Sampling step: sampling from the washing water and adding a small amount of probe solution to obtain the washing water to be tested. Detection step: using a detection mechanism to detect the fluorescence response value S of the washing water to be tested, Determination step: judging whether the detergent concentration of the washing water to be tested is a stain cleaning concentration according to whether the detected fluorescence response value S reaches or exceeds a preset cleaning response threshold value S0; if it does not reach the preset cleaning response threshold value S0, the determination result is "no", and if it reaches or exceeds the preset cleaning response threshold value S0, the determination result is "yes", and A control step: based on the determination result of the determination step, controlling the subsequent addition of the detergent in the liquid preparation step, wherein if the determination result is "no", returning to the liquid preparation step to continue adding a second predetermined amount of detergent, and then performing subsequent sampling steps, detection steps and determination steps; if the determination result is "yes", stopping adding the detergent, outputting the determination result, Wherein, the probe solution is the ACQ fluorescent probe composition according to any one of claims 1 to 10.

17. The stain cleaning concentration determination method according to claim 16, wherein: The cleaning response threshold S0 is a fluorescence response value corresponding to the critical micelle concentration cmc of the washing water, or a fluorescence response value corresponding to the stain cleaning threshold concentration Ct. The stain removal threshold concentration Ct is the minimum concentration required to clean clothes with different stains, and is determined by the following formula 3: Ct= cmc×(1+ a) (Formula 3) In Formula 3, cmc is the critical micelle concentration of the washing water, and a is the cleaning coefficient, which ranges from 0≤a≤10. Depending on the type and degree of dirtiness of the stains, a may take different values.

18. The stain cleaning concentration determination method according to claim 16, wherein: The cleaning response threshold S0 is determined by the following formula 4 or formula 5: S0= β×S max (Formula 4) S0 = S blank + β×(S max - S blank ) (Equation 5) In the formula, S max is the maximum fluorescence intensity or the maximum voltage response value of the washing water, or the second platform value in the fluorescence response value-concentration curve of the washing water; S blank is the background fluorescence intensity or minimum voltage response value of the washing water, or the first platform value in the fluorescence response value-concentration curve of the washing water; β is the threshold percentage, the unit is 100%, and the range is 0<β<1. Corresponding to different types and degrees of dirtiness of stains, β can take different values.

19. A method for controlling the amount of detergent added, characterized in that: The following steps are included: Liquid preparation step: in the washing device, a first predetermined amount of the detergent is added into the inner barrel according to the weight of the laundry and the amount of water inlet, and mixed with the water in the inner barrel to obtain washing water or detergent solution; Sampling step: collecting a predetermined amount of the washing water or detergent solution from the inner barrel as a sample; Liquid collection step: Take out a small amount of probe solution and add it to the sample. Mixing step: mixing the sample and the probe solution to obtain a test solution; Detection step: detecting the fluorescence response value of the test liquid and outputting a detection signal S; Determination step: receiving the detection signal S, and determining whether the detergent concentration of the test liquid reaches the critical micelle concentration cmc or the preset cleaning threshold concentration Ct according to whether the detection signal S reaches or exceeds the preset response threshold S0, wherein the cleaning threshold concentration Ct is greater than or equal to the critical micelle concentration cmc; and Controlling step: Based on the judgment result of the judging step, controlling the subsequent addition of the detergent, wherein if the judgment result is that the critical micelle concentration or the preset cleaning threshold concentration has not been reached, returning to the liquid preparation step to continue adding a second predetermined amount of the detergent into the inner barrel; if the judgment result is that the critical micelle concentration or the preset cleaning threshold concentration has been reached, stopping adding the detergent, Wherein, the probe solution is the ACQ fluorescent probe composition according to any one of claims 1 to 10.

20. The detergent dispensing control method according to claim 19, wherein: The control step also includes a number limiting step: presetting a number threshold representing the maximum number of times the detergent is added. If, after the detergent has been added more than once, although the judgment result of the judgment step is still that the critical micelle concentration or the preset cleaning threshold concentration has not been reached, the number of times the detergent has been added has reached the number threshold, then stop adding the detergent in the liquid preparation step.

21. A detergent dispensing control system, which is used to automatically control the amount of detergent dispensed in a washing device, the washing device comprising: An inner tub for placing laundry and water to be washed; A storage device for storing detergent; and a dispensing device for dispensing a first predetermined amount of the detergent into the inner barrel, mixing and stirring with the water in the inner barrel to obtain washing water or a detergent solution, characterized in that: The detergent delivery control system comprises: A liquid storage device, used for storing a probe solution; a sampling device for collecting a predetermined amount of the washing water or detergent solution from the inner tub as a sample; A liquid taking device, used for taking out a small amount of probe solution from the liquid storage device and adding it to the sample; Mixing device: used for mixing the sample and the probe solution to obtain a test solution; A detection device, used to detect the fluorescence response value of the test liquid and output a detection signal S; A judging device: used for receiving the detection signal S, and judging whether the detergent concentration of the test liquid reaches the critical micelle concentration cmc or the preset cleaning threshold concentration Ct according to whether the detection signal S reaches or exceeds the preset response threshold S0, wherein the cleaning threshold concentration Ct is greater than or equal to the critical micelle concentration cmc; a CMC determination device, for, under the condition that there is no laundry in the inner barrel, using the dispensing device to dispense a predetermined amount of the detergent into the inner barrel in batches, and using the liquid storage device, the sampling device, the liquid taking device, the mixing device and the detection device to repeatedly perform multiple groups of measurements, and determining the critical micelle concentration of the detergent solution according to a plurality of detection data corresponding to different detergent concentrations output by the detection device; and a control device, for controlling the subsequent delivery of the detergent by the delivery device of the washing device based on the determination result of the determination device, Wherein, if the judgment result of the judgment device is that the critical micelle concentration cmc or the preset cleaning threshold concentration Ct has not been reached, the control device controls the dispensing device to continue to dispense the second predetermined amount of the detergent into the inner barrel of the washing device; if the judgment result of the judgment device is that the critical micelle concentration cmc or the preset cleaning threshold concentration Ct has been reached or exceeded, the control device controls the dispensing device to stop dispensing the detergent; Wherein, the probe solution is the ACQ fluorescent probe composition according to any one of claims 1 to 10.

22. The detergent dispensing control system according to claim 21, wherein: The cleaning response threshold S0 is a fluorescence response value corresponding to the critical micelle concentration cmc of the detergent solution, or a fluorescence response value corresponding to the stain cleaning threshold concentration Ct. The critical micelle concentration cmc is a pre-determined critical micelle concentration of a detergent solution, or a critical micelle concentration of a detergent solution or washing water determined online by the cmc determination device. The cleaning threshold concentration Ct is calculated using the following formula 3: Ct= cmc×(1+ a) (Formula 3) Where a is the cleaning coefficient, ranging from 0≤a≤10. Depending on the type and degree of dirtiness of the stains, a can take different values. Alternatively, the cleaning response threshold S0 is determined by the following formula 4 or formula 5: S0= β×S max (Formula 4) S0 = S blank + β×(S max - S blank ) (Equation 5) In the formula, S max is the maximum fluorescence intensity or the maximum voltage response value of the washing water, or the second platform value in the fluorescence response value-concentration curve of the washing water; S blank is the background fluorescence intensity or minimum voltage response value of the washing water, or the first platform value in the fluorescence response value-concentration curve of the washing water; β is the threshold percentage, the unit is 100%, and the range is 0<β<1. Corresponding to different types and degrees of dirtiness of stains, β can take different values.

23. The detergent dispensing control system according to claim 21 or 22, wherein: The control device also sets a number threshold indicating the maximum number of times the detergent is dispensed. After the dispensing device has dispensed the detergent more than once, if the judgment result of the judgment device is still that the critical micelle concentration or the preset cleaning threshold concentration has not been reached, but the number of times the detergent has been dispensed has reached the number threshold, the control device controls the dispensing device to stop dispensing the detergent.

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