AIE fluorescent probe composition, method and device for measuring cmc of surfactant solution, method and device for determining cmc

Abstract

The present invention provides an AIE fluorescent probe composition for measuring the critical micelle concentration cmc of a surfactant solution, comprising a probe compound and an auxiliary, wherein the probe compound is a hydrophobic AIE molecule, and the auxiliary is at least one organic solvent represented by the following general formula (1), (R n -X (1), where R is a substituted or unsubstituted linear or branched alkyl group having 3 to 10 carbon atoms, n is an integer of 1 or 2, and when n is 2, the two Rs may be the same or different, and X is any polar group selected from the group consisting of a hydroxyl group, an amino group, a cyano group, a halogen group, an amide group, a carbonyl group, an aldehyde group, an ester group, and an ether group. The present invention further provides a method and device for measuring the cmc of a surfactant solution using the above-mentioned AIE fluorescent probe composition, and a method and device for determining the cmc by the AIE fluorescent probe.

Description

[Technical field]

[0001] The present invention relates to an AIE fluorescent probe composition, a method and device for measuring the cmc of a surfactant solution using the AIE fluorescent probe composition, and a method and device for determining the cmc using an AIE fluorescent probe. [Background technology]

[0002] Critical Micelle Concentration (CMC) is an important dividing line for the solution properties of surfactants. Many of the physicochemical properties of surfactant solutions, such as surface tension, light scattering, molar conductivity, density, osmotic pressure, and solubilization action, all change significantly before and after the CMC.

[0003] Conventional methods for detecting cmc include surface tension method, electrical conductivity method, and fluorescence spectroscopy (PL), but these methods have limitations in practical application, such as the need for a series of complicated operations when measuring cmc using the surface tension method, the electrical conductivity method cannot detect nonionic surfactants and surfactants with low electrical conductivity, and the fluorescence spectroscopy method has low sensitivity and relies on high-precision testing equipment.

[0004] In recent years, it has been discovered that some organic molecules do not emit light in solution, but their emission intensity is greatly enhanced in an aggregated state or in a solid thin film. Since the nature of this enhanced emission is due to molecular aggregation, this phenomenon is defined as "aggregation-induced emission" (AIE).

[0005] The AIE fluorescent probe prepared using the organic molecules exhibiting the above-mentioned AIE phenomenon can measure the CMC of surfactant solutions simply, quickly and efficiently without using precision instruments due to its aggregation-induced emission properties, and therefore can be effectively applied in various fields, such as in the cleaning industry to monitor the content of surfactants in cleaning aqueous solutions, and has practical guiding significance.

[0006] Prototype AIE molecules include, for example, common tetraphenylethylene (TPE), hexaphenylsilole (i.e., hexaphenylsilacyclopentadiene, HPS), and distyrylanthracene (DSA), and have advantages such as high quantum yield and high chemical and photostability in the solid state, but the hydrophobicity of unsubstituted prototype AIE molecules limits their application to aqueous systems such as surfactant solutions. Non-Patent Document 1 reports that hydrophobic AIE molecules are first dissolved in a volatile organic solvent such as n-hexane, then added to a surfactant solution and mixed by ultrasonic waves, and the AIE properties are exhibited after the easily soluble organic solvent is completely evaporated. However, this method includes steps such as ultrasonic mixing and evaporation of the organic solvent, making it less convenient to use in practical application environments.

[0007] In order to solve the problem of hydrophobicity of AIE fluorescent probes, the current research ideas mainly focus on introducing charged functional groups, such as ammonium groups and sulfonic acid groups, into the hydrophobic AIE molecular structure to improve its hydrophilicity. For example, in Patent Document 1, a series of hydrophilic AIE fluorescent probes are produced using a benzoquinoline structural unit as the base and a sulfonic acid group as the main water-soluble group, and the critical micelle concentration of the surfactant solution can be obtained by observing the occurrence of a sudden change from no fluorescence to the strongest fluorescence under an ultraviolet lamp with a wavelength of 365 nm. Patent Document 2 reports the synthesis of amphiphilic molecules obtained by introducing hydrophilic units into the hydrophobic skeleton of HPS molecules or TPE molecules, and their application in the biological field. However, in these methods, the synthesis technology for obtaining hydrophilic AIE molecules by derivatizing unsubstituted hydrophobic AIE molecules is difficult, the production cost is high, and general application in the industrial field is difficult. [Prior art documents] [Non-patent literature]

[0008] [Non-Patent Document 1] "Detection of the critical micelle concentration of cationic and anionic surfactants based on aggregation-induced emission property of hexaphenylsilole derivatives" TANG Li et.al,Sci China Ser B-Chem,Jun.2009,vol.52,No.6,755-759 [Patent documents]

[0009] [Patent Document 1] CN110028446A [Patent Document 2] CN106566532A Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide an AIE fluorescent probe composition that can be used to directly measure the cmc concentration of a surfactant solution without derivatizing the hydrophobic AIE molecule, and to provide a method and device for measuring the cmc of a surfactant solution using the AIE fluorescent probe composition, as well as a method and device for determining the cmc using an AIE fluorescent probe. [Means for solving the problem]

[0011] The present inventors have intensively studied the above problems and found that some hydrophobic AIE molecules dissolve in organic solvents having specific structures to form stable solutions, and exhibit remarkable AIE characteristics within an appropriate concentration range without waiting for the organic solvent to volatilize. Therefore, by using a fluorescent probe composition containing such a hydrophobic AIE molecule and a specific organic solvent, it can be directly used to measure the cmc concentration of a surfactant solution, and the above problems are preferably solved.

[0012] The present invention provides an AIE fluorescent probe composition, which is a probe solution for measuring a critical micelle concentration (cmc) of a surfactant solution, and includes a probe compound and an auxiliary, wherein the probe compound is a hydrophobic AIE molecule, and the auxiliary is at least one organic solvent represented by the following general formula (1): (R) n -X (1) Here, R is a substituted or unsubstituted linear or branched alkyl group having 3 to 10 carbon atoms, n is an integer of 1 or 2, and when n is 2, two R may be the same or different. X is characterized in that it is any polar group selected from the group consisting of a hydroxyl group, an amino group, a cyano group, a halogen group, an amide group, a carbonyl group, an aldehyde group, an ester group, and an ether group.

[0013] The present invention further provides a method for measuring the cmc of a surfactant solution, the method for measuring the cmc of the surfactant solution comprising the steps of: a solution preparation step of preparing a series of surfactant test solutions having increasing concentrations in a plurality of sample cells; a probe adding step of adding a fixed amount of a probe solution to each of the plurality of sample cells; a detection step of detecting the fluorescence intensity of each of the measurement solutions by a detection mechanism; determining a CMC concentration of the surfactant solution based on the change tendency of the detected fluorescence intensity of each of the measured solutions; The probe solution is characterized in that it is the AIE fluorescent probe composition of the present invention.

[0014] The present invention further provides a CMC measurement device for a surfactant solution, the CMC measurement device for a surfactant solution comprising: a plurality of sample cells in which a series of solutions to be measured of surfactants having increasing concentrations are prepared; a probe container containing a probe solution containing a probe compound; a sample adding mechanism for adding a quantity of the probe solution from the probe container to the plurality of sample cells; a detection mechanism for detecting a fluorescence intensity of the measurement target solution in the plurality of sample cells; a determination mechanism for determining the CMC concentration of the surfactant solution based on the change tendency of the fluorescence intensity of each measurement solution detected by the detection mechanism; The probe solution is characterized in that it is the AIE fluorescent probe composition of the present invention.

[0015] The present invention further provides a method for determining cmc by an AIE fluorescent probe, the method for determining cmc by the AIE fluorescent probe being a method for determining whether a surfactant solution reaches a critical micelle concentration (cmc), a solution preparation step of adding an initial amount of a surfactant to water and stirring the mixture to prepare a solution to be measured; a sampling step of taking a small amount of the solution to be measured and transferring it to a sample cell; a probe addition step of adding an AIE fluorescent probe to the sample cell, subjecting the sample cell to micro-vibration, and forming a mixture; a detection step of detecting the fluorescence intensity of the mixed liquid by a fluorescence detector and outputting a detection signal S; a judgment step of judging whether the critical micelle concentration cmc is reached based on the change tendency of the detection signal S, and if the judgment result is yes, outputting the concentration of the solution to be measured as the cmc concentration and terminating all steps, and if the judgment result is no, emptying the sample cell, returning to the solution preparation step, adding a predetermined amount of surfactant to the solution to be measured, and continuing to execute the next sampling step, probe addition step, detection step and judgment step, in that order; In the determination step, if the determination result is no, but the number of times the predetermined amount of surfactant is added in the solution preparation step reaches a predetermined threshold, all steps are terminated.

[0016] The present invention further provides a cmc determination device using an AIE fluorescent probe, the cmc determination device using the AIE fluorescent probe is a determination device for determining whether a surfactant solution reaches a critical micelle concentration cmc, and includes a surfactant storage mechanism, an addition mechanism, a sampling mechanism, a sample cell, an AIE fluorescent probe storage mechanism, a sample addition mechanism, a detection mechanism, a cmc determination mechanism, and a determination mechanism, and the following operations are performed in order: The adding mechanism takes out a certain amount of surfactant from the surfactant storage mechanism, mixes and stirs the surfactant with water, and prepares a solution to be measured; The sampling mechanism takes a small amount of the solution to be measured and transfers it to the sample cell; the sample addition mechanism takes out a minute amount of probe solution from a storage mechanism of the AIE fluorescent probe, adds it to the sample cell, and performs a minute vibration to form a mixed solution; The detection mechanism detects the fluorescence intensity of the mixed liquid and transmits the obtained detection signal to the CMC determination mechanism; The CMC determination mechanism determines whether or not a critical micelle concentration CMC has been reached based on a change trend of the detection signal; If the result of the determination by the CMC determination mechanism is yes, the determination mechanism outputs the concentration of the solution to be measured as a CMC concentration, and ends all operations; If the determination result of the CMC determination mechanism is NO and the number of times that the addition mechanism is executed is lower than a predetermined threshold, the sample cell is emptied, and the addition mechanism adds a predetermined amount of surfactant to the solution to be measured, and continues to execute the next operation; If the determination result of the cmc determination mechanism is no and the number of executions of the addition mechanism reaches a predetermined threshold, all operations are terminated. Effect of the Invention

[0017] The AIE fluorescent probe composition of the present invention employs an unsubstituted hydrophobic AIE molecule, and by introducing an appropriate organic solvent as an auxiliary, it can be stably and well dispersed in an aqueous system. This solves the hydrophobic problem of the unsubstituted AIE probe molecule. After the AIE fluorescent probe composition of the present invention is added to a surfactant solution, the auxiliary (i.e., organic solvent) assists the hydrophobic AIE molecule to form a stable dispersion structure in aggregates such as micelles in the surfactant solution, and the cmc concentration of the surfactant solution can be measured without the need for a volatilization step of the auxiliary, greatly improving the convenience of use in practical application scenes. In addition, the AIE fluorescent probe composition of the present invention, as a probe solution, can accurately detect the fluorescence intensity change corresponding to the cmc concentration in an appropriate concentration range using a conventional fluorescence detector, etc., thereby providing a new solution idea and research direction for the use of AIE fluorescent molecules in a wider range of fields. [Brief description of the drawings]

[0018] [Figure 1] 1A-1B are schematic diagrams of molecular simulation results illustrating the solubilization effect of the coagents of the present invention on hydrophobic AIE molecules in surfactant mixed micelles, where (A) the coagent is butylamine and (B) the coagent is butanol. [Diagram 2] This is a graph showing the change in fluorescence intensity (voltage) depending on the concentration when the AIE fluorescent probe composition of the present invention is added directly to an aqueous solution of a high-quality cleaning agent (Example 1) and when the AIE fluorescent probe composition of the present invention is not added (Reference Example 1). [Diagram 3] 1 is a graph showing the change in surface tension of the aqueous solution of the directly prepared ultra-cleaning detergent used in Example 1 according to the concentration. [Figure 4] 11 is a graph showing the change in fluorescence intensity (voltage) according to the concentration when the AIE fluorescent probe composition of the present invention is added to an aqueous solution of a cleaning agent used in actual machine washing in Example 7. [Diagram 5] 1 is a graph showing the change in interfacial tension of aqueous solutions of the actual machine-washed ultra-cleaning detergent employed in Example 7 according to concentration. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Specific embodiments of the present invention will be described below, however, the present invention is not limited to the following embodiments and can be implemented with appropriate modifications within the scope of the object of the present invention.

[0020] In this specification, a numerical range expressed using "~" is a range that includes the numerical values ​​before and after "~" as the minimum and maximum values, respectively.

[0021] In this specification, the concentration of a surfactant (which may also refer to a cleaning agent) refers to the total amount of the various surfactant components present in a surfactant solution (which may also refer to a cleaning agent solution) when multiple surfactant components are present in the surfactant solution, unless otherwise specified.

[0022] (AIE fluorescent probe composition) The AIE fluorescent probe composition of the present invention is a probe solution for measuring the critical micelle concentration cmc of a surfactant solution, and contains a probe compound and an auxiliary, the probe compound being a hydrophobic AIE molecule, and the auxiliary being at least one organic solvent represented by the following general formula (1): (R) n -X (1) Here, R is a substituted or unsubstituted linear or branched alkyl group having 3 to 10 carbon atoms, n is an integer of 1 or 2, and when n is 2, two R may be the same or different. X is characterized in that it is any polar group selected from the group consisting of a hydroxyl group, an amino group, a cyano group, a halogen group, an amide group, a carbonyl group, an aldehyde group, an ester group, and an ether group.

[0023] Each component contained in the AIE fluorescent probe composition of the present invention will be described in detail below.

[0024] "Probe Compound" The probe compound of the present invention is a hydrophobic AIE molecule having aggregation-induced emission properties.

[0025] Aggregation-Induced Emission (AIE) is a phenomenon discovered by chance in 2001 by the team of Academician Tadashi Karamoto. Some silole molecules (HPS, e.g. 1,1,2,3,4,5-hexaphenylsilole) emit almost no light in solution, but the emission intensity increases significantly in an aggregated state or as a solid thin film. Since the increase in emission intensity is due to aggregation, this phenomenon is defined as "aggregation-induced emission."

[0026] Common AIE molecules with aggregation-induced emission properties can be broadly classified into pure hydrocarbons, heteroatom-containing, macromolecular, and metal-containing structures based on their structure. Many of these molecules have aromatic conjugated planar backbones that can form helical structures in space, and their conjugation changes under the influence of different aggregation states, thereby exhibiting AIE properties in the fluorescence spectrum. Due to the presence of aromatic backbones, these molecules often exhibit hydrophobicity that makes them insoluble in water in the unsubstituted native state.

[0027] The probe compound of the present invention is preferably a hydrophobic AIE molecule containing a compound represented by any one of the following chemical formulas 1 to 12 as a basic skeleton.

[0028] [ka]

[0029] The hydrophobic AIE molecule used in the present invention preferably includes unsubstituted AIE molecules such as tetraphenylethylene (abbreviated as TPE) represented by chemical formula 1, hexaphenylsilole (abbreviated as HPS) represented by chemical formula 7, distyrenylanthracene (abbreviated as DSA) represented by chemical formula 2, and 1,12-benzoperylene (abbreviated as BP) represented by chemical formula 10, and may be a derivative, polymer, or metal complex containing the basic skeleton structure of these AIE molecules, and exhibits hydrophobicity to aqueous solutions. In the present invention, "hydrophobic" refers to the property of being insoluble or difficult to dissolve in water.

[0030] The AIE molecules exhibit completely different fluorescence performances in different aggregation or dispersion states. In addition, different types of AIE molecules may have different emission mechanisms in different solution systems. For example, tetraphenylethylene (TPE) does not emit fluorescence when dissolved in a good solvent, but generates high fluorescence emission when in a poor solvent. In the prior art, the principle of using TPE molecules to detect the cmc of various surfactant solutions is that when the surfactant concentration is low, most of the TPE molecules aggregate in the water phase, and since water is a poor solvent for the TPE molecules, the TPE molecules aggregate and generate very strong fluorescence; when the surfactant concentration is very high, the TPE molecules are wrapped in the hydrophobic core of the micelle molecules, and at this time the TPE molecules are dispersed by each micelle molecule and dispersed in the micelle core, so the internal rotation of the TPE molecules is not restricted, and the fluorescence of the TPE molecules is greatly reduced. Considering the completely different fluorescence performances in the aggregation and dispersion states, TPE can be used to detect the cmc of surfactant solutions and track the assembly and disassembly of amphiphilic molecules.

[0031] In addition, Non-Patent Document 1 reports that the cmc of a surfactant solution is measured using hydrophobic hexaphenylsilole (HPS) molecules as a probe. In this method, HPS is dissolved in a volatile organic solvent (e.g., n-hexane) and then added to an aqueous solution of a surfactant. Due to its hydrophobicity, HPS is difficult to disperse in water, and a coating layer is formed, which requires uniform mixing by ultrasonic waves. Then, after the volatilization of cyclohexane is completed, HPS enters the micelles formed by the surfactant molecules and emits strong fluorescence. In other words, when n-hexane is used as a good solvent to dissolve the HPS probe molecules, whether the solvent volatilizes or not has a dominant effect on the fluorescence results. When the solvent is not volatilized, the HPS probe molecules are preferentially dissolved in the solvent, HPS does not emit fluorescence, and the surfactant solution does not emit light, but after the solvent begins to volatilize, HPS has different degrees of precipitation, and some of them enter the hydrophobic core of the surfactant micelles and aggregate, which can exhibit the AIE characteristics that can aggregate and emit light.

[0032] However, n-hexane itself is a highly volatile colorless liquid with a low boiling point and flash point, making it difficult to store the probe solution after preparation, and the process of measuring CMC requires a solvent evaporation step. If the AIE molecule is added directly without dissolving it in an organic solvent, the amount of AIE added may be inaccurate and the mixture may be uneven, which may affect the accuracy of the test results.

[0033] [Auxiliary Agents] Through intensive research and screening, the inventors have discovered an organic solvent having a specific structure that is difficult to volatilize and that enables the AIE probe molecule to exhibit remarkable AIE properties in an appropriate concentration range as an auxiliary agent for hydrophobic AIE molecules.

[0034] Hexaphenylsilacyclopentadiene (HPS), a typical hydrophobic AIE molecule, is highly soluble in good solvents such as acetonitrile, tetrahydrofuran, and chloroform, slightly soluble in alcohols such as methanol, but completely insoluble in water. It is generally believed that the type and polarity of the solvent have little effect on the fluorescence absorption and emission spectra of HPS.

[0035] The present inventors have investigated the solubility of HPS in a series of organic solvents and the AIE performance of its surfactant solutions (for example, aqueous solutions of the Aizome Liang Zhizon detergent), and the results are shown in Table 1.

[0036] [Table 1]

[0037] As can be seen from the results in Table 1, among various organic solvents, HPS exhibits a significant AIE phenomenon in a certain cleaning agent concentration range in solvents such as n-butanol and n-pentanol, and is slightly soluble in water, slightly soluble in HPS, and does not easily volatilize, making it suitable as an auxiliary contained in the probe composition of the present invention. In particular, n-butanol is more preferable as an auxiliary of the present invention because it can exhibit a significant AIE phenomenon within an appropriate cleaning agent concentration range (e.g., 0.1 g / L to 0.2 g / L).

[0038] As can be seen from the results of further investigation, not only organic alcohols but also organic solvents having a specific amphiphilic structure can be used as the auxiliary of the present invention.The characteristics of these organic solvents are that they have an alkyl chain of a certain length in the molecule and a polar group (functional group) at the end or middle of the alkyl chain, thereby forming an amphiphilic structure having a hydrophilic region made of the polar group and a hydrophobic region made of the alkyl chain in the molecule.

[0039] That is, the auxiliary agent contained in the AIE fluorescent probe composition of the present invention is at least one organic solvent represented by the following general formula (1): (R) n -X (1) Here, R is a substituted or unsubstituted linear or branched alkyl group having 3 to 10 carbon atoms, n is an integer of 1 or 2, and when n is 2, two R may be the same or different. X is any polar group selected from the group consisting of a hydroxyl group, an amino group, a cyano group, a halogen group, an amide group, a carbonyl group, an aldehyde group, an ester group, and an ether group.

[0040] The solubility of the hydrophobic AIE molecule of the present invention in the auxiliary is soluble or slightly soluble, and is higher than the solubility in water.In this way, when the probe composition is added to an aqueous system such as a low-concentration surfactant solution, the probe compound tends to preferentially dissolve in the auxiliary, and to be stably dispersed in the aqueous system with the assistance of the auxiliary.Therefore, the hydrophobic AIE molecule of the present invention dissolves in the auxiliary to form a stable probe solution.

[0041] From the viewpoint of long-term storage stability, these auxiliary molecules are preferably organic solvents that do not volatilize easily. In general, the more volatile an organic solvent is, the lower its boiling point is, and the higher its boiling point is, the less likely it is to volatilize. Therefore, in the present invention, the boiling point of the auxiliary is preferably higher than 70°C, more preferably 70 to 155°C, and even more preferably 75 to 150°C.

[0042] In general formula (1), n ​​is preferably 1 from the viewpoint of dispersing the probe compound more stably, that is, the hydrophilic region consisting of the polar group X is preferably located at the end of the alkyl molecular chain.

[0043] R in the general formula (1) is a substituted or unsubstituted linear or branched alkyl group having 3 to 10 carbon atoms, where the size of the number of carbon atoms of R reflects the length of the alkyl chain in the auxiliary molecule. If the alkyl chain is too short, the formed hydrophobic region may be insufficient to stabilize the AIE molecule, and the solubilizing effect of the AIE molecule entering the surfactant micelle may be insufficient, and if the number of carbon atoms is too small, the volatility of the auxiliary molecule may be too large, which is disadvantageous to the storage stability of the probe solution. On the other hand, if the alkyl chain is too long, the water solubility of the auxiliary itself decreases, which is also disadvantageous to the stabilization of the probe solution, and the effect of solubilizing the AIE molecule in the surfactant micelle may not be achieved. From the viewpoint of further enhancing the effect of solubilization in the micelle and maintaining the stability of the probe solution, R in the general formula (1) is preferably an unsubstituted linear or branched alkyl group having 3 to 6 carbon atoms, more preferably 4 to 5 carbon atoms.

[0044] Moreover, the polar group X in the general formula (1) is preferably selected from a hydroxyl group or an amino group from the viewpoints of safety, availability and water solubility of the auxiliary molecule.

[0045] The auxiliary is more preferably one or more selected from the group consisting of n-propanol, isopropanol, t-butanol, n-butanol, n-butylamine, and pentylamine. The auxiliary may be a single type or a mixture of two or more types.

[0046] Different types of auxiliary agents can be selected for different AIE molecules, and are not particularly limited. In the AIE fluorescent probe composition of the present invention, a preferred combination of a hydrophobic AIE molecule and an auxiliary agent includes a combination in which the AIE molecule is unsubstituted HPS, TPE, DSA or benzoperylene, and the auxiliary agent is an organic alcohol or organic amine having 3 to 5 carbon atoms.

[0047] The present inventors have also found that the preparation method of the probe solution also has a certain effect on the fluorescence performance of the AIE fluorescent probe composition. For example, when a mixed solvent of an organic alcohol having 3 to 5 carbon atoms and acetone is used as an auxiliary, the volatility of acetone may affect the aggregation state of the AIE molecules, so that a stable and significant AIE phenomenon may not occur. However, when the AIE probe molecule is dissolved in acetone in advance, the acetone is volatilized and dried, and then the above organic alcohol is added to obtain a solution of the AIE fluorescent probe composition, a stable and significant AIE phenomenon occurs within an appropriate concentration range. This is presumably because the AIE probe molecule is first dissolved in acetone, volatilized, and dried, and then the microaggregation state of the molecule changes.

[0048] The present inventors speculate as follows about the mechanism by which the AIE fluorescent probe composition causes the AIE phenomenon in a surfactant solution.

[0049] First, the hydrophobic AIE molecule dissolves in the organic solvent, which is the auxiliary, to form a probe solution. When the probe solution containing the probe compound and the auxiliary is added to the surfactant solution, if the concentration of the surfactant is low and does not reach the critical micelle concentration, the auxiliary has a certain amphiphilic structure, so that it adsorbs or wraps the hydrophobic AIE molecule and stably disperses in the aqueous surfactant solution; when the concentration of the surfactant increases to the critical micelle concentration cmc, a large amount of surfactant molecules begin to self-assemble to form micelles; at this time, the auxiliary molecules do not need to be volatilized excessively, and enter the internal cavity of the micelles formed by the surfactant molecules together with the hydrophobic AIE molecules, and are arranged alternately with the surfactant molecules forming the micelles to form a "palisade" structure; the AIE molecules are aggregated near the palisade layer of the micelles, and this aggregation state causes strong AIE emission.

[0050] In other words, in the AIE fluorescent probe composition of the present invention, the auxiliary not only plays the role of a solvent for the hydrophobic AIE molecule, but also has the characteristics of an amphiphilic structure of hydrophilic and hydrophobic regions, so that it can assist the hydrophobic AIE molecule to enter the barrier layer of the surfactant micelle, and has a solubilizing effect on the hydrophobic AIE molecule in the micelle, allowing it to exhibit remarkable AIE properties within an appropriate concentration range.

[0051] In order to verify the above speculated mechanism, the present inventors carried out the following molecular simulation experiment.

[0052] FIG. 1 is a schematic diagram of molecular simulation results illustrating the solubilization effect of the coagent of the present invention on hydrophobic AIE molecules in surfactant mixed micelles, where (A) the coagent is butylamine and (B) the coagent is butanol.

[0053] For the auxiliary molecules, molecular simulation experiments selected a variety of polar organic solvents such as butylamine, pentylamine, pentanol, propylamine, butanol, butylaldehyde, butyric acid, isopropanol, n-propanol, and t-butanol, and for the AIE fluorescent probe molecule, benzoperylene was selected and molecular simulation experiments were conducted on its solubilization in mixed micelles (1:1) of sodium aliphatic alcohol polyether sulfate ester (AES) and aliphatic alcohol polyoxyethylene ether (AEO).

[0054] First, a 21nm*21nm*21nm ball micelle cubic water box was constructed, and each molecule was simulated with the United-Atom force field and gromacs software under NPT controlled pressure for 50ns. As a result, it was found that stable micelles were formed in each system, but because the solubility of the auxiliary molecules in water was different, the size and shape of the micelles formed were different, and the number of auxiliary molecules solubilized in the micelles and dispersed in water was different.

[0055] As can be seen from Figure 1, when the auxiliary 1 is (A) butylamine or (B) butanol, a stable ball micelle model is obtained in both cases, and the fluorescent probe molecule benzopyrene 2 (large dark spot in Figure 1) is solubilized inside the micelle in both cases. The surfactant molecule 3 forms a micelle skeleton and covers the fluorescent probe molecule. As can be seen from this, the micelles formed when butylamine is used as the auxiliary are more regular than those formed when butanol is used.

[0056] The inventors also calculated the distance from each fluorescent probe molecule to the water molecule layer, and all of them were greater than 0.2 nm, which further explains that the fluorescent probe molecule and the water molecule are isolated and solubilized in the micelle kernel. In addition, by comparing the number of hydrogen bonds, it can be seen that butylamine, etc., has low solubility in water and is more likely to form micelles with surfactants, and can play a role in stabilizing the micelles.

[0057] As can be seen from the above molecular simulation results, each system of the AIE fluorescent probe composition of the present invention can form stable micelles, and the auxiliary molecules are involved in the formation of micelles, which are located close to the polar groups of the palisade layer of the surfactant micelles, and have a positive contribution to the formation of mixed surfactant micelles and the coating of AIE fluorescent probe molecules.

[0058] In view of the present results, the molecular model constructed is reasonable, the method is feasible, and the results are reasonable.

[0059] [Other ingredients] The AIE fluorescent probe composition of the present invention may contain other components, such as additives such as stabilizers and preservatives, in addition to the hydrophobic AIE molecule which is the probe compound and the specific organic solvent which is the auxiliary, so long as they do not affect the AIE effect.

[0060] When other components are contained, the total content of the other components is preferably lower than 5 mass % and more preferably lower than 1 mass % based on the total amount of the AIE fluorescent probe composition.

[0061] In the present invention, the content ratio of the auxiliary agent and the probe compound in the AIE fluorescent probe composition is not particularly limited as long as it can reach an appropriate AIE intensity. The content ratio of the auxiliary agent to the entire AIE fluorescent probe composition is preferably 40% by mass to 90% by mass, more preferably 50% by mass to 80% by mass, and the content ratio of the probe compound to the entire AIE fluorescent probe composition is preferably 10% by mass to 60% by mass, more preferably 20% by mass to 50% by mass. The AIE fluorescent probe composition may also contain only the auxiliary agent and the probe compound.

[0062] In the AIE fluorescent probe composition of the present invention, the concentration of the hydrophobic AIE molecule as the probe compound is preferably 500 to 2000 μmol / L, more preferably 600 to 1500 μmol / L, from the viewpoints of the solubility, storage stability and AIE emission intensity of the probe solution. After the AIE fluorescent probe composition is added to the surfactant solution to be measured, the concentration of the probe compound in the surfactant solution is preferably 1 to 1000 μmol / L, more preferably 10 to 500 μmol / L.

[0063] The probe composition of the present invention adopts a hydrophobic AIE molecule as a probe compound and an organic solvent with a specific amphiphilic structure as an auxiliary agent, thereby forming a stable probe solution. The auxiliary agent also plays the effect of solubilizing the hydrophobic AIE molecule in the mixed micelles of the surfactant, and exhibits remarkable AIE properties within an appropriate concentration range. Furthermore, the probe solution of the present invention can accurately measure the cmc after being added to the test sample without the need to volatilize the solvent, which greatly improves the convenience of use in actual scenes and meets the actual application demands in measuring the cmc concentration of the surfactant solution of the AIE fluorescent probe.

[0064] (Method of measuring CMC of surfactant solution) By using an AIE fluorescent probe composition containing a hydrophobic AIE molecule as a probe molecule and a specific organic solvent as an auxiliary, as in the present invention, the composition can be used directly to measure the cmc concentration of a surfactant solution (detergent solution) in the form of a stable probe solution.

[0065] The AIE fluorescent probe composition of the present invention contains a neutrally charged hydrophobic AIE molecule, which is less susceptible to interference from charge interactions compared to derivatized hydrophilic AIE molecules, and can therefore be applied to various types of surfactants.

[0066] The surfactant of the present invention may contain at least one of an anionic surfactant, a nonionic surfactant, a cationic surfactant, and an amphiphilic surfactant. It is more preferable that the surfactant of the present invention contains at least an anionic surfactant and / or a nonionic surfactant.

[0067] Examples of the anionic surfactant include surfactants of alkyl sulfate type, alkyl alcohol polyether sulfate type, alkyl carboxylate type, alkyl sulfonate type, and phosphate type.

[0068] Examples of nonionic surfactants include alkyl glucosides, alkyl alcohol ether glucosides, polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, polyoxyethylene fatty acid esters, and fatty acid alkanolamides.

[0069] In the surfactant solution which is the solution to be measured, the above-mentioned surfactant components may be used alone or in combination of two or more kinds.

[0070] The surfactant solution may also contain a fluorescent whitening agent.

[0071] The method for measuring the critical micelle concentration (cmc) of a surfactant solution according to the present invention is as follows: a solution preparation step of preparing a series of surfactant test solutions having increasing concentrations in a plurality of sample cells; a probe adding step of adding a fixed amount of a probe solution to each of the plurality of sample cells; a detection step of detecting the fluorescence intensity of each of the measurement solutions by a detection mechanism; determining a CMC concentration of the surfactant solution based on the change tendency of the detected fluorescence intensity of each measured solution; The probe solution is characterized in that it is the AIE fluorescent probe composition of the present invention.

[0072] When hexaphenylsilacyclopentadiene (HPS) is adopted as the probe compound, it is found that in the detection step, the fluorescence intensity of each measured solution in multiple sample cells suddenly changes from low to high, and then gradually weakens after reaching the maximum fluorescence intensity; therefore, in the determination step, the concentration of the measured solution in the sample cell corresponding to the detected maximum fluorescence intensity is determined as the cmc concentration of the surfactant solution.

[0073] Preferably, the concentration of the probe compound in the AIE fluorescent probe composition is 500 to 2000 μmol / L, and the concentration of the probe compound in the surfactant solution is 1 to 1000 μmol / L.

[0074] Preferably, the increasing concentration range of the series of surfactants is 0 to 20 g / L, and the probe solution is added in a volume ratio to the surfactant solution of 1:1000 to 100:1000.

[0075] With the above method, since there are multiple sample cells, each containing a series of increasing concentrations of surfactant, the intensity of fluorescence in each sample cell can be intuitively determined, and the sample cell with the highest fluorescence intensity can be determined with the naked eye even without a fluorescence detection device, making it easy to measure the CMC concentration of the surfactant solution.

[0076] Alternatively, instead of multiple sample cells, only one sample cell may be used. In this case, a surfactant solution with an initial concentration is prepared in the sample cell, a certain amount of fluorescent probe is added to form a mixture, and the fluorescence intensity of the mixture is detected. Then, a certain amount of surfactant is added to the sample cell a certain number of times, and the fluorescence intensity of the mixture is measured each time the surfactant is added, and the CMC concentration of the surfactant solution is determined based on the change trend of the detected fluorescence intensity. This measurement method has the advantage that the amount of reagent used is reduced and costs are saved because only one probe addition and a certain number of surfactant additions are required.

[0077] (CMC measurement device for surfactant solutions) The present invention further provides an apparatus for measuring the critical micelle concentration cmc of a surfactant solution, said apparatus comprising: a plurality of sample cells in which a series of solutions to be measured of surfactants having increasing concentrations are prepared; a probe container containing a probe solution containing a probe compound; a sample adding mechanism for adding a quantity of the probe solution from the probe container to the plurality of sample cells; a detection mechanism for detecting a fluorescence intensity of the measurement target solution in the plurality of sample cells; a determination mechanism for determining the CMC concentration of the surfactant solution based on the change tendency of the fluorescence intensity of each measurement solution detected by the detection mechanism; The probe solution is characterized in that it is the AIE fluorescent probe composition of the present invention.

[0078] The probe compound is preferably an HPS molecule. When the HPS molecule is used as a fluorescent probe, the detected fluorescence intensity changes from low to high, and the strongest fluorescence intensity occurs in the sample cell corresponding to the cmc concentration.

[0079] The detection mechanism is preferably a fluorescent sensor having an excitation wavelength range of 275 to 375 nm and a receivable wavelength range that includes at least 350 to 370 nm or 720 to 740 nm, and outputs a detection signal of fluorescence intensity by detecting a change in the peak intensity of the fluorescence emission peak in the wavelength range of 350 to 370 nm or 720 to 740 nm of the surfactant solution.

[0080] (Cmc determination method using AIE fluorescent probe) One application field of the AIE fluorescent probe composition of the present invention is as a smart marker for online determination of a smart dosing system of detergent in a cleaning machine.

[0081] Current washing equipment, such as automatic dosing washing machines, mainly doses detergent according to the weight of the fabric load, and is not smart, and is not versatile for different detergents or applicable to each washing scene, leaving room for significant improvement. The goal of the smart judgment of the washing machine automatic dosing system is not to indicate the point where the laundry is completely cleaned or basically cleaned, but to indicate the point where the dirt removal efficiency is the best or the point where the cost performance is the best.

[0082] The inventors' research has shown that after the concentration of a detergent containing a surfactant component reaches the critical micelle concentration, its cleaning effect reaches an optimal balance point of cost performance. Therefore, whether the aqueous solution of the detergent reaches the cmc concentration can be used as a basis for determining whether to smartly dispense the detergent.

[0083] Therefore, the present invention further provides a method for determining cmc by an AIE fluorescent probe, the method being for determining whether a surfactant reaches a critical micelle concentration cmc, a solution preparation step of adding an initial amount of a surfactant to water and stirring the mixture to prepare a solution to be measured; a sampling step of taking a small amount of the solution to be measured and transferring it to a sample cell; a probe addition step of adding an AIE fluorescent probe to the sample cell, subjecting the sample cell to micro-vibration, and forming a mixture; a detection step of detecting the fluorescence intensity of the mixed liquid by a fluorescence detector and outputting a detection signal S; a judgment step of judging whether the critical micelle concentration cmc is reached based on the change tendency of the detection signal S, and if the judgment result is yes, outputting the concentration of the solution to be measured as the cmc concentration and terminating all steps, and if the judgment result is no, emptying the sample cell, returning to the solution preparation step, adding a predetermined amount of surfactant to the solution to be measured, and continuing to execute the next sampling step, probe addition step, detection step and judgment step, in that order; In the determination step, if the determination result is no, but the number of times the predetermined amount of surfactant is added in the solution preparation step reaches a predetermined threshold, all steps are terminated.

[0084] The surfactant solution employed in the cmc determination method of the present invention may be an aqueous solution of a detergent prepared directly or in an actual machine washing device, which contains one or more surfactant components, including at least anionic surfactants and / or nonionic surfactants.

[0085] In the present invention, an AIE fluorescent probe having aggregation-induced emission properties is used as a marker, and therefore a normal fluorescence detector with low sensitivity is used to accurately measure the fluorescence intensity of the aqueous solution of the detergent, and the fluorescence intensity is converted into a detection signal S, thereby enabling online determination of the CMC and smart control of the amount of detergent added.

[0086] The AIE fluorescent probe used in the cmc determination method of the present invention may be a fluorescent probe aqueous solution containing a water-soluble AIE molecule, or may be an AIE fluorescent probe composition containing the hydrophobic AIE molecule of the present invention and an auxiliary. From the viewpoints of cost, applicability, and convenience, it is preferable to use the AIE fluorescent probe composition of the present invention.

[0087] The aqueous solution of detergent to which HPS molecules, an AIE fluorescent probe, was added had a green-yellow fluorescence that could be observed with the naked eye within a certain concentration range, and the fluorescence intensity first increased and then became significantly weaker. In the case of the aqueous solution of detergent prepared directly, the concentration range corresponding to the strongest fluorescence intensity roughly observed with the naked eye was around 0.1g / L to 0.2g / L, and the fluorescence intensity decreased significantly when the concentration of the detergent was >2g / L.

[0088] In order to realize automatic control of the cleaning equipment, the fluorescence intensity of the mixed liquid detected by the fluorescence detector must be output as a detection signal S, which is a voltage signal corresponding to the fluorescence intensity F at a specific wavelength, and output to a judgment mechanism or decision mechanism described below.

[0089] Regarding the threshold value S0, a series of surfactant test solutions having gradually increasing concentrations can be prepared in advance in multiple sample cells or in a single sample cell using the above-mentioned CMC measurement method for surfactant solutions, and the detection signal S corresponding to the maximum detected fluorescence intensity can be set as the threshold value S0.

[0090] Next, in a judgment step, if the detection signal S is equal to or greater than a preset threshold value S0, the judgment result is YES (the aqueous solution of the cleaning agent has reached the cmc concentration), and if the detection signal S is lower than the threshold value S0, the judgment result is NO (the aqueous solution of the cleaning agent has not reached the cmc concentration).

[0091] However, the cmc concentration of the detergent solution in the actual machine washing machine is affected by many factors (such as water temperature, fabric weight, etc.), so the preset threshold value S0 may not correspond to the actual cmc concentration, and the apparent cmc concentration of the detergent solution in the actual machine washing is usually much higher than the cmc concentration corresponding to the threshold value S0. In this case, it is preferable to add detergent little by little during the actual washing process, and use the cmc determination method of the present invention to determine the apparent cmc concentration of the detergent solution online, so as to realize smart addition of detergent according to the result.

[0092] In the judgment step that is executed two or more times, the detection signal S X , S Y It is preferable to determine whether the concentration of the surfactant reaches the critical micelle concentration cmc by observing the change in the difference between the concentrations.

[0093] More specifically, in the two adjacent detection signals, the latter detection signal S Y and the previous detection signal S X Difference S Y -S X is 0 or a negative value, the judgment result is YES (the aqueous solution of the cleaning agent has reached the cmc concentration), and the difference S Y -S X If is greater than 0, the result is no (the aqueous solution of the cleaning agent has not reached the cmc concentration).

[0094] When the above CMC judgment method is applied to the actual cleaning process of a cleaning equipment, the judgment step is mainly used to determine whether or not a cleaning agent needs to be added. After adding the cleaning agent for the first time, the cleaning equipment can start cleaning, and multiple sampling and judgment can be performed during the cleaning process, or cleaning can start after all steps are completed.

[0095] In the method for determining the cmc using the AIE fluorescent probe of the present invention, an AIE fluorescent probe having aggregation-induced emission properties is adopted, so that a normal low-sensitivity fluorescent detector can be adopted without using precision instruments, and the change in AIE fluorescence intensity can be recognized by the naked eye alone. Therefore, the cmc of the aqueous solution of detergent can be determined simply, quickly and efficiently, and can be effectively applied to the online monitoring of the content of detergent in the detergent aqueous solution in the cleaning industry, which has practical guiding significance in the smart addition of detergent.

[0096] (Cmc determination device using AIE fluorescent probe) The present invention further provides a cmc determination device using an AIE fluorescent probe, the cmc determination device being a determination device for determining whether a surfactant solution reaches a critical micelle concentration cmc, comprising a surfactant storage mechanism, an addition mechanism, a sampling mechanism, a sample cell, an AIE fluorescent probe storage mechanism, a sample addition mechanism, a detection mechanism, a cmc determination mechanism, and a determination mechanism, wherein the following operations are carried out in order: The adding mechanism takes out a certain amount of surfactant from the surfactant storage mechanism, mixes and stirs the surfactant with water, and prepares a solution to be measured; The sampling mechanism takes a small amount of the solution to be measured and transfers it to the sample cell; the sample addition mechanism takes out a minute amount of probe solution from a storage mechanism of the AIE fluorescent probe, adds it to the sample cell, and performs a minute vibration to form a mixed solution; The detection mechanism detects the fluorescence intensity of the mixed liquid and transmits the obtained detection signal to the CMC determination mechanism; The CMC determination mechanism determines whether or not a critical micelle concentration CMC has been reached based on a change trend of the detection signal; If the result of the determination by the CMC determination mechanism is yes, the determination mechanism outputs the concentration of the solution to be measured as a CMC concentration, and ends all operations; If the determination result of the CMC determination mechanism is NO and the number of times that the addition mechanism is executed is lower than a predetermined threshold, the sample cell is emptied, and the addition mechanism adds a predetermined amount of surfactant to the solution to be measured, and continues to execute the next operation; If the determination result of the cmc determination mechanism is no and the number of executions of the addition mechanism has reached a predetermined threshold, all operations are terminated.

[0097] The AIE fluorescent probe employed by the device is preferably the above-mentioned AIE fluorescent probe composition of the present invention.

[0098] When applying the above device to an actual cleaning device, it is possible to determine whether to add a surfactant (cleaning agent) based only on the determination result of the cmc determination mechanism without outputting the cmc concentration. The determination mechanism can control the cleaning device to start cleaning after the first detection operation is completed or after all operations are completed.

[0099] The detection mechanism may be a fluorescence sensor with an excitation wavelength range of 275 - 375 nm and a receivable emission wavelength range of 350 - 750 nm, and preferably a fluorescence sensor with an excitation wavelength range of 275 - 375 nm and including at least 350 - 370 nm or 720 - 740 nm in the receivable wavelength range.

[0100] The HPS molecule, which is an AIE fluorescent probe, has two fluorescence intensity emission peaks when excited by 365 nm ultraviolet light, namely a sharp and strong fluorescence peak in the range of 350 - 370 nm and a relatively weak and narrow fluorescence peak in the range of 720 - 740 nm, and does not overlap with the emission peak of the fluorescent whitening agent (such as CBS) contained in the aqueous solution of the actual cleaning agent (for example, the Supreme Clean Detergent and Supreme Bright White Detergent manufactured by Blue Moon). That is, it avoids the wavelength range of 400 - 550 nm where the emission peak of the fluorescent whitening agent CBS appears. In this way, the interference with the cmc determination result of the fluorescent whitening agent can be avoided.

[0101] By adopting the cmc determination method and device using the AIE fluorescent probe of the present invention, it can be actually applied to a cleaning device to perform online detection, online determination of cmc, and automatic addition of a cleaning agent, so it can be applied to the smart input system of the cleaning agent for the cleaning device.

Example

[0102] Hereinafter, the present invention will be further specifically described by examples, but the present invention is not limited to the following examples as long as its gist is not deviated from.

[0103] (Example 1) <Preparation of AIE Fluorescent Probe Composition> The probe compound, HPS (98% purity, molecular weight M = 538.7 ) was dissolved in n-butanol, an auxiliary, so that the concentration was 0.001 mol / L to prepare a probe solution.

[0104] <Preparation of a measurement solution containing a surfactant> As the test solution containing a surfactant, Shison Kiyosaku detergent B1-B10 (product name, manufactured by Aizetsuryo Co., Ltd.) was directly prepared into a series of aqueous solutions of detergent with concentrations of 0.02 g / L, 0.05 g / L, 0.1 g / L, 0.2 g / L, 0.5 g / L, 1 g / L, 2 g / L, 5 g / L, 10 g / L, and 20 g / L, and 150 μL of the above probe solution was added to 5 mL of the above detergent aqueous solution to prepare the test solution.The concentration of the HPS probe in the test solution was 30 μmol / L.

[0105] (Reference Example 1) A control was run by preparing a test solution containing the surfactant of Reference Example 1 in the same manner as in Example 1, except that no probe solution was added.

[0106] <Measurement of fluorescence intensity> A customized and assembled fluorescence detector (optical filters include an excitation light filter (365 nm), a dichroic mirror, and an emission light filter (729 nm); the light source has a peak wavelength of 365 nm, a wavelength range of 300-400 nm, an operating current of 0.02 A, and an operating voltage of 5 V) was used to perform fluorescence detection on the measurement solution to which the above HPS probe was added, and the fluorescence intensity was detected according to the brightness of the fluorescence emission (the emission intensity is converted into a readable display number of the effective voltage). The results of Example 1 and Reference Example 1 are shown in Figure 2.

[0107] <Determination of cmc concentration of aqueous solution of cleaning agent> FIG. 2 is a graph showing the change in fluorescence intensity depending on the concentration when the AIE fluorescent probe composition of the present invention is added to the aqueous solution of the supreme cleaning detergent prepared directly as described above (Example 1, black circle in the figure) and when the AIE fluorescent probe composition of the present invention is not added (Reference Example 1, black square in the figure).

[0108] As can be seen from FIG. 2, when no probe solution is added, the fluorescence intensity of the aqueous solution of the detergent is very low, and the intensity hardly changes with increasing concentration of the detergent (Reference Example 1).

[0109] In contrast, in the aqueous solution of the detergent to which the probe solution (HPS-n-butanol) of the present invention of Example 1 was added, a certain intensity of fluorescence was observed even when the concentration of the aqueous detergent solution was low (lower than cmc). This is presumably because, after the detergent and HPS probe molecules were added to the system, the mixture of HPS / surfactant started to aggregate due to the hydrophobic interactions between the alkyl chains of the surfactant in the detergent and the π-π interactions between the HPS molecules, which formed a regular structure or a complex structure, effectively restricting the intramolecular motion, thereby exhibiting a certain aggregation emission characteristic.

[0110] When the concentration of the detergent solution in the system reaches or exceeds the cmc (10 times lower than the cmc), the surfactant molecules self-assemble in large quantities to form micelles. The micelles at this time are often ball-shaped, and the size and shape of the micelles remain almost unchanged. Driven by hydrophilic-hydrophobic interactions, the lipophilic (hydrophobic) HPS probe molecules enter the hydrophobic core of the ball-shaped micelles with the assistance of an auxiliary (n-butanol) and aggregate, exhibiting strong AIE characteristics with strong fluorescence intensity within the concentration range of 0.1 to 2 g / L. The concentration of the solution to be measured corresponding to the peak value (maximum fluorescence intensity) of the curve in Figure 2 is 0.1 g / L, so that concentration can be directly determined as the cmc concentration of the prepared detergent solution.

[0111] When the concentration of the detergent solution in the system is too high (e.g., more than 10 times the cmc), the intensity of the fluorescence emission is significantly reduced, which is believed to be because, at an excessive surfactant concentration, ball-shaped micelles form anisotropic aggregates such as worm-shaped micelles or vesicles, HPS is distributed into micelles or aggregates of different shapes, the π-π interactions between HPS molecules are destroyed, the intramolecular motion restriction of HPS molecules is weakened, and the excited molecules consume light energy in the form of heat energy etc. through rotational vibrational forms, resulting in weaker fluorescence of HPS. It is also speculated that the fluorescence intensity observed by the naked eye may be significantly weakened due to the effect of the fluorescence anisotropy of the HPS probe in the environment of non-ball-shaped micellar aggregates.

[0112] The change in the AIE fluorescence intensity of the aqueous solution of the above-mentioned ultra-cleaning detergent can also be recognized by the naked eye alone. The concentration of the solution to be measured with the strongest fluorescence intensity as seen by the naked eye is determined as the cmc concentration, and the observation results basically coincide with the measurement results using the above-mentioned fluorescence detector.

[0113] In order to further verify the accuracy of the cmc measurement results using the AIE fluorescent probe composition of the present invention, the cmc was measured for the aqueous solution of the supreme cleaning detergent used in Example 1 using a K100C surface tensiometer, and a graph showing the change in surface tension according to concentration was obtained, as shown in Figure 3.

[0114] By fitting the change curve in Figure 3, the cmc of the directly prepared aqueous solution of the supreme cleaning detergent is estimated to be ≒ 0.09 g / L, which is close to the measurement result (0.1 g / L) using the AIE fluorescent probe method of the present invention, indicating that the cmc measurement method using the AIE fluorescent probe composition of the present invention is feasible and effective.

[0115] (Examples 2 to 6, Comparative Examples 1 to 3, Reference Example 2) Except for using Shison Brightening Detergent A0-A10 (product name, manufactured by Aizue Liang Co., Ltd.) containing the fluorescent brightener CBS instead of Shison Cleaning Detergent B1-B10 and changing the composition of the AIE fluorescent probe composition as shown in Tables 2-1 and 2-2 below, the test solutions of Examples 2 to 6 and Comparative Examples 1 to 3 were directly prepared in the same manner as in Example 1 and similar measurements were performed.

[0116] In addition, a control was performed by preparing the test solution of Reference Example 2 in the same manner as in Example 2, except that no probe solution was added. The results are shown in Tables 2-1 and 2-2. In the tables, the bold numbers in the voltage value column indicate the voltage value corresponding to the maximum fluorescence intensity (peak value).

[0117] [Table 2-1]

[0118] [Table 2-2]

[0119] As can be seen from Tables 2-1 and 2-2, in Examples 2 to 6 of the present invention, the concentration of the test solution corresponding to the maximum fluorescence intensity is 0.2 g / L in all cases, even though different types of assistants are used. Therefore, this concentration can be determined as the cmc concentration of the aqueous solution of the ultimate whitening detergent prepared directly.

[0120] Furthermore, as shown in Example 6, even when HPS was dissolved in acetone in advance and then evaporated to dryness, and n-butanol was added, a stable and significant AIE phenomenon similarly occurred within an appropriate concentration range, and the maximum fluorescence intensity was observed near the cmc concentration.

[0121] In contrast, since the number of carbon atoms in the alkyl chain in the auxiliary molecule (aminomethylacetone) used in Comparative Example 1 does not satisfy the requirement of general formula (1) of the present invention, no significant AIE phenomenon is observed within the concentration range of 0 to 20 g / L.

[0122] In Comparative Example 2, a mixed solvent of n-butanol and acetone was used, but acetone itself does not meet the requirements of the general formula (1) of the present invention, and the uncertainty of the volatility of acetone in the mixed solvent makes the change trend of the emission intensity of the measured solution unstable, making it impossible to accurately measure the CMC concentration. This result shows that if the volatile solvent in the probe solution is not completely volatilized, the measurement result will be inaccurate.

[0123] In Comparative Example 3, acetone was directly used as an auxiliary agent, and measurements were performed after acetone had completely evaporated. From the experimental results, a significant AIE phenomenon was observed after acetone had completely evaporated. However, due to the very volatile nature of acetone, a stable probe solution could not be prepared, and it was necessary to wait for the solvent to evaporate during the measurement process. Therefore, this is not suitable as a probe solution of the present invention, and is outside the scope of the present invention, making this a Comparative Example.

[0124] Example 7 <Preparation of aqueous solution of cleaning agent for actual machine cleaning> A 2.5kg weight of clothes was put into a drum washing machine, 13L of water and 1g of the Supreme Cleaning Detergent B0-B10 (trade name, manufactured by Aizue Liang Co., Ltd.) were added and stirred, and then a certain amount of detergent was added during the washing in the washing machine, and the amount of detergent added to the 13L of water was 1g, 2g, 4g, 8g, 12g, 16g, 20g, 24g, 28g, and 32g, respectively, and the corresponding concentrations of the Supreme Cleaning Detergent were 0.075g / L, 0.15g / L, 0.31g / L, 0.62g / L, 0.92g / L, 1.23g / L, 1.54g / L, 1.85g / L, 2.15g / L, and 2.46g / L, respectively. The aqueous solutions of the detergents used in the actual machine washing, containing a series of detergents with different concentrations, were used as the test solutions and were taken out of the drum washing machine in sequence.

[0125] In Example 7, the fluorescence intensity was measured in the same manner as in Example 1, except that the aqueous solution of the detergent actually used for machine washing was used instead of the directly prepared aqueous solution of the detergent used in Example 1. The results are shown in FIG. 4.

[0126] FIG. 4 is a graph showing that the fluorescence intensity changes with concentration when the AIE fluorescent probe composition (HPS-n-butanol) of the present invention is added to an aqueous solution of the most suitable detergent for machine washing.

[0127] As shown in Figure 4, similar to the change trend in Figure 2, as the concentration of the detergent in the detergent solution gradually increases, the fluorescence intensity of each detergent solution suddenly changes from low to high, and then gradually weakens after reaching the maximum fluorescence intensity. However, what is different from Figure 2 is that the concentration of the detergent solution corresponding to the peak value (maximum fluorescence intensity) appearing on the curve is 0.62 g / L.

[0128] As can be seen from this, in the usage scenario shown in Example 7, the cmc concentration of the actual machine washing detergent solution is 0.62 g / L. This cmc concentration is higher than the cmc concentration measured in the directly prepared detergent solution used in Example 1. This is because the actual machine washing detergent solution contains a large amount of clothes and adsorbs the detergent to a certain extent, which results in a high apparent cmc concentration, and this result is reasonable.

[0129] In order to further verify the accuracy of the cmc measurement results using the AIE fluorescent probe composition of the present invention, a K100C surface tensiometer was used to measure the cmc of the aqueous solution of the actual machine cleaning detergent used in Example 7, and a graph showing the change in surface tension according to concentration was obtained, as shown in Figure 5.

[0130] By fitting the change curve in FIG. 5, the cmc of the aqueous solution of the best detergent for actual machine washing is estimated to be ≒ 0.7 g / L, which is close to the measurement result (0.62 g / L) using the AIE fluorescent probe method of the present invention, indicating that the cmc measurement method using the AIE fluorescent probe composition of the present invention is feasible and effective.

[0131] As is clear from the results of Examples 1 to 7 above, the AIE fluorescent probe composition of the present invention can form a stable probe solution and is applicable to both direct preparation and aqueous solutions of detergents used in actual machine washing. It also avoids the interference of fluorescent brighteners in aqueous solutions of detergents and exhibits AIE characteristics within an appropriate CMC concentration range, so that it can be applied to actual applications such as cleaning equipment to accurately and easily measure the CMC concentration of aqueous solutions of detergents.

[0132] "Industrial Applicability" By adopting the AIE fluorescent probe composition of the present invention, it is not necessary to adopt high-precision testing equipment, and it is possible to realize online measurement and online judgment of the cmc concentration of a surfactant solution with only a simply assembled fluorescent detector in the ultraviolet-visible light range, which facilitates industrialization and plays an important role in the smart addition system of detergent in cleaning equipment.

Claims

1. 1. An aggregation-induced emission (AIE) fluorescent probe composition that is a probe solution for measuring the critical micelle concentration (cmc) of a surfactant solution, comprising: The probe compound is a hydrophobic AIE molecule, and the auxiliary is at least one organic solvent represented by the following general formula (1): the hydrophobic AIE molecule is dissolved in the auxiliary; (R) n -X (1) In the formula, R is a substituted or unsubstituted linear or branched alkyl group having 3 to 10 carbon atoms, n is an integer of 1 or 2, and when n is 2, two R may be the same or different; X is a polar group selected from the group consisting of a hydroxyl group, an amino group, a cyano group, a halogen group, an amide group, a carbonyl group, an aldehyde group, an ester group, and an ether group; 1. An AIE fluorescent probe composition comprising:

2. The boiling point of the coagent is greater than 70° C. The AIE fluorescent probe composition according to claim 1 .

3. In the general formula (1), R is an unsubstituted linear or branched alkyl group having 3 to 6 carbon atoms, and X is selected from a hydroxyl group and an amino group. The AIE fluorescent probe composition according to claim 1 .

4. The co-agent is at least one selected from the group consisting of n-propanol, isopropanol, t-butanol, n-butanol, n-butylamine, and pentylamine; The AIE fluorescent probe composition according to claim 1 .

5. the auxiliary has an amphiphilic structure and has a hydrophilic region composed of the polar group and a hydrophobic region composed of the substituted or unsubstituted linear or branched alkyl group having 3 to 10 carbon atoms in the molecule; and the probe compound has a higher solubility in the auxiliary than in water. The AIE fluorescent probe composition according to claim 1 .

6. The auxiliary is an alkyl alcohol having 3 to 6 carbon atoms, and the method for preparing the probe solution is to dissolve the probe compound in acetone in advance, then evaporate and dry the solution, and finally add the alkyl alcohol to obtain the AIE fluorescent probe composition. The AIE fluorescent probe composition according to claim 1 .

7. The probe compound is a hydrophobic AIE molecule having a compound represented by any one of the following chemical formulas 1 to 12 as a basic skeleton: The AIE fluorescent probe composition according to claim 1 . 【Chemistry 1】

8. The hydrophobic AIE molecule is unsubstituted tetraphenylethylene (TPE) represented by the chemical formula 1, unsubstituted distyrylanthracene (DSA) represented by the chemical formula 2, unsubstituted hexaphenylsilacyclopentadiene (HPS) represented by the chemical formula 7, or unsubstituted benzoperylene (BP) represented by the chemical formula 10; The AIE fluorescent probe composition according to claim 7.

9. The concentration of the probe compound in the AIE fluorescent probe composition is 500 to 2000 μmol / L, and the concentration of the probe compound in the surfactant solution is 1 to 1000 μmol / L; The AIE fluorescent probe composition according to claim 1 .

10. The content ratio of the auxiliary to the entire AIE fluorescent probe composition is 70% by mass to 99% by mass, and the content ratio of the probe compound to the entire AIE fluorescent probe composition is 1% by mass to 30% by mass. The AIE fluorescent probe composition according to claim 1 .

11. A method for determining whether a surfactant solution reaches a critical micelle concentration (cmc) using an AIE fluorescent probe, comprising: a solution preparation step of adding an initial amount of a surfactant to water and stirring the mixture to prepare a solution to be measured; a sampling step of taking a small amount of the solution to be measured and transferring it to a sample cell; a probe addition step of adding an AIE fluorescent probe to the sample cell and subjecting the sample cell to micro-vibration to form a mixture; a detection step of detecting the fluorescence intensity of the mixed solution by a fluorescence detector and outputting a detection signal S; a determining step of determining whether or not a critical micelle concentration (cmc) is reached based on a change tendency of the detection signal S, and if the determination result is yes, outputting the concentration of the solution to be measured as cmc and terminating all steps, and if the determination result is no, emptying the sample cell, returning to the solution preparation step, adding a predetermined amount of surfactant to the solution to be measured, and continuing to execute the next sampling step, probe addition step, detection step and determination step, in that order; In the determination step, if the determination result is "no" but the number of times the predetermined amount of surfactant has been added in the solution preparation step has reached a predetermined threshold, all steps are terminated; A method for determining cmc using an AIE fluorescent probe, characterized in that the AIE fluorescent probe is an AIE fluorescent probe composition according to any one of claims 1 to 10.

12. In the determination step, the detection signal S is a preset threshold value S 0 If so, the determination result is YES, and the detection signal S is equal to or greater than the threshold value S 0 If it is lower than, the result is no. The cmc determination method according to claim 11.

13. In the determination step, the detection signal S of the latter step is determined based on the detection signals obtained in two adjacent detection steps. Y and the previous detection signal S X Difference S Y -S X If the difference S is 0 or a negative value, the result of the judgment is yes, and Y -S X is greater than 0, the determination is negative; The cmc determination method according to claim 11.

14. The surfactant solution contains at least an anionic surfactant and / or a nonionic surfactant. The cmc determination method according to claim 11.

15. A determination device for determining whether a surfactant solution reaches a critical micelle concentration (cmc), the cmc determination device using an AIE fluorescent probe includes a surfactant storage mechanism, an addition mechanism, a sampling mechanism, a sample cell, an AIE fluorescent probe storage mechanism, a sample addition mechanism, a detection mechanism, a cmc determination mechanism, and a determination mechanism, the adding mechanism takes out a certain amount of surfactant from the surfactant storage mechanism, mixes and stirs the surfactant with water, and prepares a solution to be measured; The sampling mechanism extracts a small amount of the solution to be measured and transfers it to the sample cell; the sample adding mechanism takes out a minute amount of probe solution from a storage mechanism for the AIE fluorescent probe, adds it to the sample cell, and performs minute vibration to form a mixed solution; The detection mechanism detects a fluorescence intensity of the mixed liquid and transmits a detection signal obtained to the CMC determination mechanism; The cmc determination mechanism determines whether or not a critical micelle concentration (cmc) is reached based on a change trend of the detection signal, If the determination result of the cmc determination mechanism is yes, the determination mechanism outputs the concentration of the solution to be measured as cmc and ends all operations; or If the determination result of the cmc determination mechanism is no and the number of times that the dosing mechanism is executed is less than a predetermined threshold, empty the sample cell, and allow the dosing mechanism to add a predetermined amount of surfactant to the solution to be measured, and continue to execute the next operation; or If the determination result of the cmc determination mechanism is no and the number of executions of the addition mechanism reaches a predetermined threshold, all operations are terminated; 11. A cmc determination device using an AIE fluorescent probe, wherein the AIE fluorescent probe is an AIE fluorescent probe composition according to any one of claims 1 to 10.

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