Determination method for dichlorphenol in textile or leather

Abstract

The invention provides a method for determining diclofenac in textiles or leather, and provides a scheme for detecting diclofenac in textiles or leather by adopting a liquid chromatography tandem mass spectrometer to solve the problem that in the prior art, derivation is involved, and extra reagents and manpower need to be consumed. The method specifically comprises the following steps: adding a first volume of methanol solution into a to-be-detected sample, and performing ultrasonic extraction for first specified time to obtain an extracting solution; transferring the extracting solution into a small purification column, and discarding effluent; eluting and purifying the small column by adopting an eluting solvent with a second volume to obtain an eluent; nitrogen-blowing the eluent until the eluent is completely dried, adding a third volume of methanol for redissolving, and filtering to obtain a loading test solution; and detecting the content of diclophenol in the loading test solution through a liquid chromatography tandem mass spectrometer. According to the method, derivatization reaction does not need to be carried out, dichlorphenol is directly detected, the detection time is greatly shortened, operation is convenient, the detection limit reaches 0.01 mg / kg, and the detection requirement for the residual quantity of dichlorphenol in textiles or leather is met.

Description

Technical Field

[0001] The present application relates to the field of chemical detection, and in particular to a method for determining dichlorophenol in textiles or leather. Background Art

[0002] Reference Figure 2 and Figure 3 , which are the chemical formula and chromatogram of dichlorophenol respectively. Dichlorophenol is also known as bactericide algaecide NL-4, CAS: 97-23-4. It is a highly effective and broad-spectrum fungicide. It can also be used as a preservative and mildew preventer for natural adhesives and synthetic rubber latex. Due to its efficient bactericidal ability, it is widely used in agricultural planting and textile processing. Although most of the target substances will be removed during the processing of textiles and leather, they may still remain in the final product. The residual dichlorophenol is easily absorbed by the human body through the skin and is toxic to the human body. The OEKO-TEX International Environmentally Friendly Textile and Leather Association released it in 2024. In STANDARD 100, dichlorophen has been updated from the monitored pesticide list to the official pesticide list. At the same time, clear limit requirements have been made for the dichlorophen residues on textiles, requiring that the dichlorophen residues in infant textile products shall not exceed 0.5 mg / kg, and the dichlorophen residues in other types of textile materials shall not exceed 1.0 mg / kg.

[0003] The existing technology can be used to derivatize dichlorophenol and acetic anhydride to obtain phenyl acetate derivatives, and then the content of phenyl acetate is determined by gas chromatography after organic solvent extraction, and then the content of dichlorophenol is calculated. The existing method involves derivatization, which requires additional reagents and manpower. Summary of the invention

[0004] In view of the above problems, the present application is proposed to provide a method for determining dichlorophenol in a textile or leather that overcomes the above problems or at least partially solves the above problems, comprising:

[0005] A method for determining dichlorophen in textiles or leather comprises the steps of:

[0006] Adding a first volume of methanol solution to the sample to be tested, and ultrasonically extracting for a first designated time to obtain an extract;

[0007] Transferring the extract to a purification column and discarding the effluent;

[0008] eluting the purification column with a second volume of elution solvent to obtain an eluate;

[0009] The eluted liquid nitrogen was blown to dryness, and a third volume of methanol was added for redissolution, and filtered to obtain a test solution for the machine;

[0010] The content of dichlorophen in the upper machine test solution is detected by liquid chromatography tandem mass spectrometry.

[0011] Furthermore, it also includes:

[0012] Cut the sample to be tested into small pieces of 3mm×3mm;

[0013] Weigh 1 g of the sample to be tested into a test tube.

[0014] Furthermore, the first volume is 10 ml.

[0015] Furthermore, the first designated time is (30±2) min.

[0016] Further, the step of transferring the extract to a purification column and discarding the effluent comprises:

[0017] Pre-activating the purification column with methanol;

[0018] The extract was completely transferred to the purification column, and the effluent was discarded.

[0019] Furthermore, the elution solvent is acetone and n-hexane, and the volume ratio of acetone to n-hexane is 9:1.

[0020] Furthermore, the second volume is 10 ml.

[0021] Furthermore, the third volume is 1 mL.

[0022] Furthermore, the liquid chromatography parameters of the liquid chromatography tandem mass spectrometer are:

[0023] Chromatographic column: Eclipse XDB-C18, 5μm, 2.1mm×150mm; mobile phase A: 5mmol / L ammonium acetate aqueous solution; mobile phase B: acetonitrile; column temperature: 30℃; injection volume: 5μL; column flow rate: 0.40mL / min;

[0024] Liquid phase elution gradient:

[0025]

[0026] Furthermore, the tandem mass spectrometer parameters of the liquid chromatography tandem mass spectrometer are:

[0027] Mass spectrometer model ABSCIEX TripleQuad 4500 Air curtain gas 35 Collision gas 6 Ion spray voltage Negative mode: -4500 Ion source temperature 600℃ Ion source gas 1 50 Ion source gas 2 50 Ionization mode Electrospray ESI Acquisition Mode Multiple reaction monitoring mode MRM

[0028]

[0029] This application has the following advantages:

[0030] In the embodiments of the present application, relative to the prior art involving derivatization, the need to spend additional reagents and manpower, the present application provides a solution for detecting dichlorophenol in textiles or leather using a liquid chromatography tandem mass spectrometer, specifically: adding a first volume of methanol solution to the sample to be tested, ultrasonically extracting for a first specified time, and obtaining an extract; transferring the extract to a purification column, and discarding the effluent; eluting the purification column with a second volume of elution solvent to obtain an eluent; blowing the elution liquid nitrogen to dryness, and adding a third volume of methanol for redissolution, filtering to obtain a machine test solution; detecting the content of dichlorophenol in the machine test solution by a liquid chromatography tandem mass spectrometer. The present application does not require a derivatization reaction, can directly detect dichlorophenol, greatly shortens the detection time of this project, is easy to operate, and the detection limit can reach 0.01 mg / kg, which can meet the detection requirements for the residual amount of dichlorophenol in textiles or leather. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solution of the present application, the following is a brief introduction to the drawings required for use in the description of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0032] Figure 1 This is a flow chart of the steps of a method for determining dichlorophenol in textiles or leather provided in one embodiment of the present application;

[0033] Figure 2 is the chemical formula of dichlorophen;

[0034] Figure 3 This is the chromatogram of dichlorophen;

[0035] Figure 4 This is a characteristic ion mass spectrum of dichlorophen provided in an embodiment of the present application;

[0036] Figure 5 This is another characteristic ion mass spectrum of dichlorophen provided in one embodiment of the present application. DETAILED DESCRIPTION

[0037] In order to make the objects, features and advantages of the present application more obvious and understandable, the present application is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0038] The inventor found through analyzing the prior art that the existing similar dichlorophene determination method is to extract the dichlorophene in the cosmetics with acetonitrile, extract the dichlorophene in the detergent with methanol, separate it with a high performance liquid chromatograph, and perform quantitative analysis with a diode array detector. The detection limit of this method is 10 mg / kg, which cannot meet the testing requirements of textiles. Alternatively, the dichlorophene and acetic anhydride residual in the drinking water are subjected to a derivatization reaction to obtain a phenylacetate derivative, and after extraction with an organic solvent, the content of phenylacetate is determined by gas chromatography, and then the content of dichlorophene is obtained by calculation. Acetic anhydride belongs to the national precursor chemical, and is a liquid reagent with a pungent odor and corrosiveness. Its production, operation, purchase, transportation, import and export must be subject to classified management and licensing systems, so the derivatization reaction has increased manpower and reagent costs invisibly.

[0039] Reference Figure 1 , showing a method for determining dichlorophenol in textiles or leather provided in one embodiment of the present application;

[0040] The method comprises:

[0041] S110, adding a first volume of methanol solution to the sample to be tested, and ultrasonically extracting for a first specified time to obtain an extract;

[0042] S120, transferring the extract to a purification column, and discarding the effluent;

[0043] S130, eluting the purification column with a second volume of elution solvent to obtain an eluent;

[0044] S140, blowing the eluted liquid nitrogen to dryness, adding a third volume of methanol to redissolve, and filtering to obtain a test solution for the machine;

[0045] S150, detecting the content of dichlorophen in the upper machine test solution by liquid chromatography tandem mass spectrometry.

[0046] In the embodiments of the present application, in the embodiments of the present application, relative to the prior art involving derivatization, the problem of needing to spend additional reagents and manpower, the present application provides a solution for detecting dichlorophenol in textiles or leather by liquid chromatography tandem mass spectrometry, specifically: adding a first volume of methanol solution to the sample to be tested, ultrasonically extracting for a first specified time, and obtaining an extract; transferring the extract to a purification column, and discarding the effluent; eluting the purification column with a second volume of elution solvent to obtain an eluent; blowing the elution liquid nitrogen to dryness, and adding a third volume of methanol for redissolution, filtering to obtain a machine test solution; detecting the content of dichlorophenol in the machine test solution by liquid chromatography tandem mass spectrometry. The present application does not need to carry out a derivatization reaction, can directly detect dichlorophenol, greatly shortens the detection time of this project, is easy to operate, and the detection limit can reach 0.01 mg / kg, which can meet the detection requirements for the residual amount of dichlorophenol in textiles or leather.

[0047] Below, the determination method of dichlorophen in a textile or leather in this exemplary embodiment will be further described.

[0048] In one embodiment of the present application, it also includes:

[0049] Cut the sample to be tested into small pieces of 3mm×3mm;

[0050] Weigh 1 g of the sample to be tested into a test tube.

[0051] It should be noted that this step is to extract a small amount of target substance from the target object for detection. It is one of the effective ways to obtain the target object for testing and obtain various data without affecting the main properties of the target object. The amount of the extracted object must be sufficient for 3-5 tests. The sampling area selection process for the object to be tested is required to be random.

[0052] As an example, the sample to be tested is cut into small pieces of 3 mm×3 mm, mixed evenly, and set aside. 1 g of the sample to be tested (accurate to 0.1 mg) is weighed into a glass test tube.

[0053] As described in step S110, a first volume of methanol solution is added to the sample to be tested, and ultrasonic extraction is performed for a first designated time to obtain an extract.

[0054] It should be noted that this step is to pretreat the sample to be tested. Pretreatment is generally a step of removing impurities and purifying the target object before carrying out effective processes. In some special experiments, the pretreatment step also includes the purpose of changing the properties of the substance. In this embodiment, it is preferred to use ultrasound to pretreat the sample to be tested.

[0055] In this embodiment, the first volume is 10 ml; the first designated time is (30±2) min.

[0056] As an example, weigh 1g of textile or leather sample, add 10mL of methanol, and extract in an ultrasonic extractor at room temperature for (30±2)min. Methanol is used as the extraction solvent, and ultrasound is used as the extraction instrument. Dichlorophene has good solubility in methanol, ensuring that the target compound can be effectively transferred from the sample to the methanol solvent, thereby improving the efficiency and accuracy of the extraction; methanol as a solvent has good compatibility with liquid chromatography tandem mass spectrometry, improving the accuracy and reliability of the analysis.

[0057] As described in step S120, the extract is transferred to a purification column and the effluent is discarded.

[0058] In one embodiment of the present invention, the specific process of "transferring the extract to a purification column and discarding the effluent" in step S120 can be further explained in combination with the following description.

[0059] Pre-activate the cleanup cartridge with methanol as described in the following steps;

[0060] As described in the following steps, the extract is transferred entirely to the purification column and the flow-through is discarded.

[0061] In a specific implementation, the filler of the purification column is silica gel, and the specification is 500mg / 6mL. The separation principle of silica gel chromatography is to separate substances according to their different adsorption forces on silica gel. Generally, substances with larger polarity are easily adsorbed by silica gel, and substances with weaker polarity are not easily adsorbed by silica gel. The entire chromatography process is adsorption, desorption, re-adsorption, and re-desorption process, thereby realizing the separation and purification of compounds. Silica gel is called the stationary phase, which is the static phase of silica gel column chromatography separation. During the chromatography process, the compounds on the stationary phase are affected by affinity, and the compounds are adsorbed on the surface of the stationary phase, and the substances that are not adsorbed are separated and removed.

[0062] As described in step S130, the purification column is eluted with a second volume of elution solvent to obtain an eluate.

[0063] In a specific implementation, the second volume is 10 ml. The elution solvent is acetone and n-hexane, and the volume ratio of acetone to n-hexane is 9:1. Elution changes the properties of the mobile phase so that the compounds adsorbed on the stationary phase gradually dissolve into the mobile phase, thereby achieving separation and purification of the compounds. The eluate flowing out of the silica gel column is collected in a nitrogen blowpipe, and the solution can be further processed and analyzed.

[0064] As described in step S140, the eluted liquid nitrogen is blown to dryness, and a third volume of methanol is added for redissolution, and filtered to obtain a test solution for the machine.

[0065] As an example, the eluent is blown dry with nitrogen using a nitrogen blower, 1 mL of methanol is added for redissolution, filtered with a 0.22 μm filter membrane, and analyzed using a liquid chromatography tandem mass spectrometer (LC-MS / MS). Filtration can improve the purity of the test solution on the machine, avoid the influence of impurities, and improve the detection accuracy.

[0066] As described in step S150, the content of dichlorophen in the upper machine test solution is detected by liquid chromatography tandem mass spectrometry.

[0067] In this example, a Thermo Fisher U3000 / ABSCIEX high performance liquid chromatography tandem mass spectrometer was used for qualitative and quantitative analysis.

[0068] The liquid chromatography parameters of the high performance liquid chromatograph are:

[0069] Chromatographic column: Eclipse XDB-C18, 5μm, 2.1mm×150mm; mobile phase A: 5mmol / L ammonium acetate aqueous solution; mobile phase B: acetonitrile; column temperature: 30℃; injection volume: 5μL; column flow rate: 0.40mL / min.

[0070] The liquid phase elution gradient is shown in Table 1.

[0071]

[0072] Table 1 Liquid phase elution gradient The parameters of the tandem mass spectrometer of the high performance liquid chromatograph are:

[0073] Mass spectrometer model ABSCIEX TripleQuad 4500 Air curtain air 35 Collision gas 6 Ion spray voltage Negative mode: -4500 Ion source temperature 600℃ Ion source gas 1 50 Ion source gas 2 50 Ionization mode Electrospray ESI Acquisition Mode Multiple reaction monitoring mode MRM

[0074] Table 2 Mass spectrometry related parameters

[0075]

[0076] Table 3 Retention time and characteristic ions of dichlorophen

[0077] Reference Figure 4 and Figure 5 , which is the characteristic ion mass spectrum of dichlorophen.

[0078] Qualitative analysis: Samples were measured under the same experimental conditions. If the retention time of the detected chromatographic peak was consistent with that of the standard substance, and the deviation between the quantitative ion pair (269.0 / 129.0) and the qualitative ion pair (269.0 / 127.0) did not exceed 10%, the sample was judged to contain the target compound.

[0079] Quantitative analysis:

[0080] Prepare the standard solution as follows:

[0081] Prepare the standard stock solution of dichlorophene with methanol at a concentration of 1000 mg / L. Dichlorophene working solution: Dilute the standard stock solution of dichlorophene with methanol step by step to 0 mg / L, 0.020 mg / L, 0.05 mg / L, 0.10 mg / L, 0.15 mg / L, 0.20 mg / L standard working solutions, with at least 5 concentration points.

[0082] The instrument analysis was performed under the same conditions as the sample. Then the calibration curve was made with the peak area corresponding to the concentration of the standard substance test solution, the regression equation and correlation coefficient were obtained, and the external standard method was used for quantitative analysis to calculate the residual amount of dichlorophen.

[0083] The calculation formula is:

[0084]

[0085] Where, X 1 The residual amount of dichlorophenol in textile or leather samples, in mg / kg;

[0086] C is the content of dichlorophen in the test solution, in mg / L;

[0087] C 0 is the content of dichlorophen in the blank test solution, in mg / L;

[0088] V is the final methanol volume, in mL;

[0089] m is the mass of the textile or leather sample in g.

[0090] The following are embodiments of the present invention:

[0091] The textile and leather samples were spiked with dichlorophen and three different concentration levels were tested as follows:

[0092] Analysis steps:

[0093] Cut the textile or leather sample into small pieces of 3mm×3mm and mix them evenly. Weigh 1g of textile or leather sample, add 10mL of methanol, add appropriate volume of dichlorophene standard solution so that the spiked concentration of the final sample solution is 0.02mg / L, 0.1mg / L and 0.2mg / L respectively, shake well and cover tightly. Extract at room temperature in an ultrasonic extractor for (30±2)min. The silica gel purification column is pre-activated with methanol, and all the extract is transferred to the silica gel purification column, and the effluent is discarded. Elute with 10mL of elution solvent (acetone + n-hexane = 9+1) three times, and collect the eluate into a nitrogen blowpipe. Use a nitrogen blowpipe to blow until dry, add 1mL of methanol for redissolution, filter with a 0.22μm filter membrane, and analyze by liquid chromatography tandem mass spectrometry (LC-MS / MS).

[0094] Preparation of standard solution:

[0095] The dichlorophen standard stock solution was diluted graded with methanol into standard working solutions of 0 mg / L, 0.020 mg / L, 0.05 mg / L, 0.10 mg / L, 0.15 mg / L, and 0.20 mg / L, and analyzed with the above sample extraction solutions by LC-MS / MS.

[0096] Liquid chromatography parameters.

[0097] Instrument type: Thermo Fisher U3000 high performance liquid chromatograph; Chromatographic column: Eclipse XDB-C18, 5μm, 2.1mm×150mm; Mobile phase A: 5mmol / L ammonium acetate aqueous solution; Mobile phase B: acetonitrile; Column temperature: 30℃; Injection volume: 5μL; Column flow rate: 0.4mL / min. Liquid phase elution gradient is shown in Table 1.

[0098] Tandem mass spectrometer parameters.

[0099] Mass spectrometer model: ABSCIEX TripleQuad 4500; curtain gas (CUR): 35; collision gas (CAD): 6; ion spray voltage (IS) negative mode: -4500; ion source temperature (TEM): 600°C; ion source gas 1 (GS1): 50; ion source gas 2 (GS2): 50; ionization mode: electrospray ESI; acquisition mode: multiple reaction monitoring mode MRM; MRM quantitative ion pair: 269 / 129, MRM qualitative ion pair: 269 / 127.

[0100] After the above analysis experiment was completed, a peak consistent with the retention time of the characteristic ion pair of the target compound appeared in the retention time window, and the result deviation of the quantitative ion pair (269 / 129) and the qualitative ion pair (269 / 127) did not exceed 10%. The retention time of the target compound dichlorophen was 7.41min, and the retention time and qualitative ion pair concentration of all analyzed samples were within the allowable deviation range.

[0101] The standard curve linear equation, correlation coefficient (R2), test results and precision are shown in Table 4 below:

[0102]

[0103] It can be seen from Table 4 that the detection limit of this embodiment is as low as 0.01 mg / kg, and the recovery rate is 84%-92%, which is relatively high. This shows that the present invention uses methanol as the extraction solvent and ultrasound as the extraction instrument. Through specific elution steps, independent exploration and optimization of instrument parameters such as liquid chromatography-tandem mass spectrometer separation heating program and data acquisition parameters, the target compound and impurities can be effectively separated.

[0104] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present application.

[0105] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.

[0106] The above is a detailed introduction to the method for determining dichlorophenol in a textile or leather provided by the present application. Specific examples are used herein to illustrate the principle and implementation method of the present application. The description of the above embodiments is only used to help understand the method and its core idea of ​​the present application. At the same time, for those skilled in the art, according to the idea of ​​the present application, there will be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as limiting the present application.

Claims

1. A method for determining dichlorophen in textiles or leather, characterized in that, Includes steps: Adding a first volume of methanol solution to the sample to be tested, and ultrasonically extracting for a first designated time to obtain an extract; Transferring the extract to a purification column and discarding the effluent; eluting the purification column with a second volume of elution solvent to obtain an eluate; The eluted liquid nitrogen was blown to dryness, and a third volume of methanol was added for redissolution, and filtered to obtain a test solution for the machine; The content of dichlorophen in the upper machine test solution is detected by liquid chromatography tandem mass spectrometry.

2. The detection method according to claim 1, characterized in that: Also includes: Cut the sample to be tested into small pieces of 3mm×3mm; Weigh 1 g of the sample to be tested into a test tube.

3. The detection method according to claim 1, characterized in that: The first volume was 10 ml.

4. The detection method according to claim 1, characterized in that: The first designated time is (30±2) min.

5. The detection method according to claim 1, characterized in that: The step of transferring the extract to a purification column and discarding the effluent comprises: Pre-activating the purification column with methanol; The extract was completely transferred to the purification column, and the effluent was discarded.

6. The detection method according to claim 1, characterized in that: The elution solvent is acetone and n-hexane, and the volume ratio of acetone to n-hexane is 9:

1.

7. The detection method according to claim 1, characterized in that: The second volume was 10 ml.

8. The detection method according to claim 1, characterized in that: The third volume is 1 mL.

9. The detection method according to claim 1, characterized in that: The liquid chromatography parameters of the liquid chromatography tandem mass spectrometer are: Chromatographic column: Eclipse XDB-C18, 5μm, 2.1mm×150mm; Mobile phase A: 5mmol / L ammonium acetate aqueous solution; Mobile phase B: acetonitrile; Column temperature: 30°C; injection volume: 5 μL; column flow rate: 0.40 mL / min; Liquid phase elution gradient:

10. The detection method according to claim 1, characterized in that: The tandem mass spectrometer parameters of the liquid chromatography tandem mass spectrometer are:

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