Method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry

Abstract

The invention relates to a method for detecting 23 volatile organic compounds in nail polish through gas chromatography-mass spectrometry, and belongs to the technical field of chemical analysis. The method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry comprises the following steps: (1) pretreating a nail polish sample to obtain a test solution; (2) preparing a series of standard solutions; (3) qualitative analysis; (4) sequentially measuring the standard solutions, carrying out linear regression by taking the series concentrations of the to-be-measured components as horizontal coordinates and the peak areas of the to-be-measured components as vertical coordinates, and establishing a standard curve; and (5) measuring the test solution, substituting the corresponding quantitative ion chromatographic peak area into the linear regression equation, and calculating the content of each component in the nail polish sample. According to the method, various volatile organic compounds including 12 forbidden raw materials and 11 potential risk substances in the nail polish can be effectively identified and quantitatively analyzed, and reliable data support is provided for supervision departments.

Description

Technical Field

[0001] This application relates to the technical field of chemical analysis, and particularly to a method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry. Background Art

[0002] In the existing technical field, for the detection methods of volatile components in cosmetics, especially the methods specified in the "Technical Specifications for Cosmetics Safety" (2015 Edition), due to the early drafting time, the investigation of the types of cosmetic matrices is lacking, and there are certain limitations and deficiencies. In the actual application process, when it comes to nail polish, a specific type of cosmetic, its guiding role seems inadequate. First of all, the specification does not provide detailed classification guidance for applicable cosmetic categories, which leads to a lack of specific operation guidelines when dealing with products of different natures. Secondly, for products such as nail polish with unique physical and chemical properties, the determination procedures in the current standard are too complex, and during the experiment, the determination results of important volatile substances such as benzene and its homologues show poor repeatability, which obviously cannot meet the requirements of accurate and reliable detection. In addition, in the academic research field, there are only a small number of studies on the types of volatile components in nail polish, but the specific content determination methods for these components are relatively scarce. Especially when the target components are complex, the existing methods often can only analyze a single type of compound (such as halogenated hydrocarbons), which further limits its universality and effectiveness in practical applications. And nail polish cosmetics are the type of cosmetics with the highest detection rate of volatile organic compounds. Therefore, developing a more accurate, efficient and applicable method for determining the volatile components of nail polish cosmetics has become an urgent technical need. Summary of the Invention

[0003] In view of this, this application provides a method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry. This application can effectively identify and quantitatively analyze various volatile organic compounds in nail polish, including 12 prohibited raw materials and 11 potential risk substances, and can effectively overcome the defects existing in the above-mentioned prior art.

[0004] The first aspect of this application provides a method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry, including the following steps:

[0005] (1) Pretreat the nail polish sample to obtain a test solution;

[0006] (2) Weigh the corresponding masses of the reference substances respectively and prepare individual standard stock solutions; then measure the individual standard stock solutions for mixing, dilute with hexane and make up to the mark to prepare a mixed standard solution; respectively pipette the mixed standard solution and dilute it stepwise to form a series of standard solutions;

[0007] (3) Take the test solution and the corresponding standard solution and measure them under the same test conditions. If chromatographic peaks of quantitative ions and qualitative ions appear in the test solution, the retention time of the characteristic ion peak of the component to be measured shall be consistent with the corresponding retention time of the standard solution, and the maximum deviation of the relative abundance ratio of the selected qualitative ions from the relative abundance ratio of the qualitative ions in the standard solution of the corresponding concentration shall not exceed the corresponding value, then it can be determined that the corresponding test component exists in the nail polish sample;

[0008] (4) Measure the standard solution successively. Using the series of concentrations of the component to be measured as the abscissa and the peak area of the component to be measured as the ordinate, perform linear regression to establish a standard curve;

[0009] (5) Measure the test solution, substitute the peak area of the corresponding quantitative ion chromatographic peak into the linear regression equation, and calculate the content of each component in the nail polish sample.

[0010] This application is designed specifically for nail polish cosmetics and is used to determine the volatile organic compounds therein, with significant technical advantages. First of all, the method of this application can effectively detect various harmful substances including 12 kinds of raw materials prohibited in cosmetics, and at the same time covers 11 substances with potential risks although there are no clear limit regulations, ensuring the safety and compliance of nail polish products. Secondly, compared with traditional methods, the method of this application is only optimized for the characteristics of nail polish, avoiding the errors and inconveniences that may be brought by general methods. Most importantly, the sample preparation process of this application is simple and fast, greatly improving the detection efficiency, reducing the uncertain factors brought by manual operation, and ensuring the accuracy and reliability of the data. These series of characteristics make the method of this application an ideal choice for the detection of volatile organic compounds in nail polish products, not only simplifying the laboratory operation process, but also providing strong technical support for product quality control.

[0011] Preferably, in step (3), the relative abundance ratio of the ions is represented by k:

[0012] When k > 50%, the allowable maximum deviation value is ±20%;

[0013] When 50% ≥ k > 20%, the allowable maximum deviation value is ±25%;

[0014] When 20% ≥ k > 10%, the allowable maximum deviation value is ±30%;

[0015] When k ≤ 10%, the allowable maximum deviation value is ±50%.

[0016] Preferably, in step (2), the steps for preparing the standard solution are as follows: respectively and precisely pipette appropriate amounts of the mixed standard solution, and dilute it with hexane to obtain a series of standard solutions with the concentrations of carbon tetrachloride, trichloroethylene, chloroform, tetrachloroethylene, and α-chlorotoluene being 0.05 μg / mL, 0.1 μg / mL, 0.5 μg / mL, 1.0 μg / mL, 2.0 μg / mL, and 3.0 μg / mL respectively, a series of standard solutions with the concentrations of 1,1-dichloroethane, 1,2-dichloroethylene, 1,2-dichloroethane, isopropylbenzene, propylbenzene, and styrene being 0.1 μg / mL, 0.2 μg / mL, 1.0 μg / mL, 2.0 μg / mL, 3.0 μg / mL, and 5.0 μg / mL respectively, and a series of standard solutions with the concentrations of tetrahydrofuran, dichloromethane, benzene, toluene, ethylbenzene, p-xylene, m-xylene, o-xylene, nitrobenzene, 2-nitrotoluene, 3-nitrotoluene, and 4-nitrotoluene being 0.2 μg / mL, 1.0 μg / mL, 2.0 μg / mL, 3.0 μg / mL, and 5.0 μg / mL respectively.

[0017] Preferably, the conditions of the gas chromatography-mass spectrometry instrument are as follows:

[0018] Among them, the chromatographic conditions are as follows:

[0019] Chromatographic column: packed chromatographic column;

[0020] Carrier gas: high-purity helium gas; flow rate: 1.5 mL / min;

[0021] Programmed temperature rise: initial temperature 50 °C, hold for 3 min, rise to 110 °C at 10 °C / min, rise to 230 °C at 15 °C / min, hold for 5 min;

[0022] Direct injection; inlet temperature: 210 °C; injection volume: 1 μL; split ratio: 20:1;

[0023] The mass spectrometry conditions are as follows:

[0024] Ion source type: EI; ion source temperature: 230 °C; quadrupole temperature: 150 °C; mass spectrometry interface temperature: 230 °C;

[0025] Scanning mode: SIM, monitoring the fragment ions of 23 volatile organic compounds.

[0026] Preferably, the packed chromatographic column is selected from one of AE.PEG-20M, DB-1, and DB-WAX.

[0027] Preferably, the size of the AE.PEG-20M chromatographic column is 60 m × 0.50 μm × 0.25 mm. Specifically, the brand is Zhongke Antai.

[0028] Preferably, the specific process of step (1) is as follows: accurately weigh the nail polish sample into a stoppered centrifuge tube, precisely add the extraction solvent, vortex and shake, and take the supernatant as the test solution.

[0029] Preferably, the dosage ratio of the nail polish sample to the extraction solvent is 0.5 g: 3 mL.

[0030] Preferably, the extraction solvent is selected from one of methanol, ethanol, acetone, ethyl acetate, and n-hexane.

[0031] Preferably, the time of vortex and shake is 5 min; or

[0032] After vortex and shake, centrifugation is also carried out. The centrifugation speed is 5000 r / min and the centrifugation time is 10 min.

[0033] Compared with the prior art, the present application has the following beneficial effects:

[0034] 1. Since nail polish is one of the cosmetics with the highest detection rate of volatile organic compounds, the present application has carried out an optimized design for the unique properties of nail polish, established a detection method suitable for volatile organic compounds in nail polish cosmetics, simplified the sample pretreatment steps in the traditional detection method, made the detection process more intuitive and easy to understand, improved the detection efficiency, the spike recovery rates of each compound can reach more than 80%, and the repeatability of the measurement results meets the measurement requirements, making up for the problem of poor repeatability of the measurement results when detecting benzene and its homologues in nail polish in the standard inspection method.

[0035] 2. The present application adopts a simple and rapid sample preparation method, greatly shortening the time period from sample collection to result output, reducing the human error that may be caused by complex operations, ensuring the accuracy and consistency of the detection results, and bringing great convenience to laboratory work.

[0036] 3. The present application can effectively identify and quantitatively analyze various volatile organic compounds in nail polish, including 12 kinds of prohibited raw materials and 11 kinds of potential risk substances, providing reliable data support for the regulatory authorities, helping them better perform their supervision functions, ensuring that the nail polish products circulating in the market meet the safety standards, and protecting the health rights and interests of consumers; Generally speaking, the detection method of the present application provides a strong technical guarantee for the safety monitoring of nail polish cosmetics with its high detection ability and simple operation process. Description of the Drawings

[0037] To more clearly illustrate the technical solutions in the present application or the prior art, the following will briefly introduce the accompanying drawings required for the description of the present application or the prior art. Obviously, the accompanying drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other accompanying drawings can be obtained based on these drawings without creative efforts.

[0038] Figure 1 It is the total ion current chromatogram of the reference substance, where 1: tetrahydrofuran (5.578 min), 2: carbon tetrachloride (5.753 min), 3: 1,1-dichloroethane (6.469 min), 4: dichloromethane (6.469 min), 5: benzene (6.775 min), 6: 1,2-dichloroethylene (7.511 min), 7: trichloroethylene (7.580 min), 8: chloroform (8.033 min), 9: tetrachloroethylene (8.144 min), 10: toluene (8.502 min), 11: 1,2-dichloroethane (8.886 min), 12: ethylbenzene (10.051 min), 13: p-xylene (10.184 min), 14: m-xylene (10.295 min), 15: cumene (10.803 min), 16: o-xylene (11.020 min), 17: propylbenzene (11.370 min), 18: styrene (12.062 min), 19: α-chlorotoluene (15.126 min), 20: nitrobenzene (17.316 min), 21: 2-nitrotoluene (17.636 min), 22: 3-nitrotoluene (18.139 min), 23: 4-nitrotoluene (18.524 min);

[0039] Figure 2Total ion chromatogram of the spiked solution of the water-based nail polish sample, where 1: tetrahydrofuran (5.578 min), 2: carbon tetrachloride (5.753 min), 3: 1,1-dichloroethane (6.469 min), 4: dichloromethane (6.469 min), 5: benzene (6.775 min), 6: 1,2-dichloroethylene (7.511 min), 7: trichloroethylene (7.580 min), 8: chloroform (8.033 min), 9: tetrachloroethylene (8.144 min), 10: toluene (8.502 min), 11: 1,2-dichloroethane (8.886 min), 12: ethylbenzene (10.051 min), 13: p-xylene (10.184 min), 14: m-xylene (10.295 min), 15: isopropylbenzene (10.803 min), 16: o-xylene (11.020 min), 17: n-propylbenzene (11.370 min), 18: styrene (12.062 min), 19: α-chlorotoluene (15.126 min), 20: nitrobenzene (17.316 min), 21: 2-nitrotoluene (17.636 min), 22: 3-nitrotoluene (18.139 min), 23: 4-nitrotoluene (18.524 min);

[0040] Figure 3 Total ion chromatogram of the spiked solution of the oil-based nail polish sample, where 1: tetrahydrofuran (5.578 min), 2: carbon tetrachloride (5.753 min), 3: 1,1-dichloroethane (6.469 min), 4: dichloromethane (6.469 min), 5: benzene (6.775 min), 6: 1,2-dichloroethylene (7.511 min), 7: trichloroethylene (7.580 min), 8: chloroform (8.033 min), 9: tetrachloroethylene (8.144 min), 10: toluene (8.502 min), 11: 1,2-dichloroethane (8.886 min), 12: ethylbenzene (10.051 min), 13: p-xylene (10.184 min), 14: m-xylene (10.295 min), 15: isopropylbenzene (10.803 min), 16: o-xylene (11.020 min), 17: n-propylbenzene (11.370 min), 18: styrene (12.062 min), 19: α-chlorotoluene (15.126 min), 20: nitrobenzene (17.316 min), 21: 2-nitrotoluene (17.636 min), 22: 3-nitrotoluene (18.139 min), 23: 4-nitrotoluene (18.524 min). Detailed implementation manners

[0041] To make the objectives, technical solutions and advantages of this application clearer, the following will describe the technical solutions in this application clearly and completely in conjunction with the accompanying drawings in this application. Obviously, the described embodiments are part of rather than all of the embodiments of this application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts fall within the scope of protection of this application.

[0042] The detection method of this application is the standard curve method. For those not described in detail in the following experimental procedures and test methods, standard operating procedures are adopted, such as the operation methods for solution preparation and system suitability testing.

[0043] Instruments: Agilent gas chromatography - mass spectrometer 7890 - 5977MSD; AE240 electronic analytical balance (Mettler - Toledo Instruments Co., Ltd., Switzerland); centrifuge Neofuge15 (Shanghai Lishen); vortex oscillator Multi Reax (heidolph).

[0044] Test drugs: hexane (Merck). The information of reference substances is shown in Table 1.

[0045] Table 1 Information of reference substances

[0046]

[0047]

[0048] The chromatographic conditions are as follows:

[0049] Chromatographic column: Zhongke Antai AE.PEG - 20M (60m × 0.25mm × 0.5μm).

[0050] Carrier gas: high - purity helium gas; flow rate: 1.5 mL / min; inlet temperature: 210°C.

[0051] Programmed temperature rise: initial temperature 50°C, hold for 3 min, rise to 110°C at 10°C / min, rise to 230°C at 15°C / min, hold for 5 min.

[0052] Direct injection; injection volume: 1 μL; split ratio: 20:1.

[0053] The mass spectrometry conditions are as follows:

[0054] Ion source type: EI source; scanning mode: SIM, fragment ions are shown in Table 2.

[0055] Ion source temperature: 230°C; quadrupole temperature: 150°C.

[0056] Mass spectrometry interface temperature: 230°C; solvent delay time: 4 min.

[0057] Table of information on fragments of 223 organic compounds

[0058]

[0059] 1. Detection method

[0060] (1) Preparation of sample solution:

[0061] Accurately weigh 0.5 g of the sample into a 10 mL stoppered centrifuge tube, precisely add 3 mL of n-hexane, vortex for 5 min, centrifuge at 5000 r / min for 10 min, and take the supernatant as the test solution. (Dilute to an appropriate concentration for injection if necessary).

[0062] (2) Preparation of standard solution:

[0063] Standard stock solution: Accurately weigh 50 mg each of the standard substances tetrahydrofuran, dichloromethane, benzene, toluene, 1,2-dichloroethane, ethylbenzene, p-xylene, m-xylene, isopropylbenzene, o-xylene, propylbenzene, styrene, nitrobenzene, 2-nitrotoluene, 3-nitrotoluene, and 4-nitrotoluene; 25 mg each of carbon tetrachloride, 1,1-dichloroethane, 1,2-dichloroethylene, trichloroethylene, chloroform, tetrachloroethylene, and α-chlorotoluene, and quantitatively dilute to 10 mL with n-hexane respectively, and store frozen at -18 °C.

[0064] Mixed standard solution: Precisely pipette 1 mL of the mixed standard solution respectively, and quantitatively dilute to 50 mL with hexane, and store frozen at -18 °C.

[0065] Mixed standard series solutions: Precisely pipette appropriate amounts of the mixed standard solution respectively, and dilute with hexane to obtain standard series solutions with concentrations of carbon tetrachloride, trichloroethylene, chloroform, tetrachloroethylene, and α-chlorotoluene being 0.05 μg / mL, 0.1 μg / mL, 0.5 μg / mL, 1.0 μg / mL, 2.0 μg / mL, and 3.0 μg / mL respectively; standard series solutions with concentrations of 1,1-dichloroethane, 1,2-dichloroethylene, 1,2-dichloroethane, isopropylbenzene, propylbenzene, and styrene being 0.1 μg / mL, 0.2 μg / mL, 1.0 μg / mL, 2.0 μg / mL, 3.0 μg / mL, and 5.0 μg / mL respectively; standard series solutions with concentrations of tetrahydrofuran, dichloromethane, benzene, toluene, ethylbenzene, p-xylene, m-xylene, o-xylene, nitrobenzene, 2-nitrotoluene, 3-nitrotoluene, and 4-nitrotoluene being 0.2 μg / mL, 1.0 μg / mL, 2.0 μg / mL, 3.0 μg / mL, 5.0 μg / mL respectively.

[0066] (3) Standard substances:

[0067] Precisely measure 1 μL of the mixed standard series solution and inject it into the gas chromatography-mass spectrometer to measure the corresponding peak areas. Using the concentration of the mixed standard solution as the abscissa and the peak areas of each substance as the ordinate, plot the calibration curve. The measured spectrogram is as Figure 1 the total ion chromatogram of the reference substance, Figure 2 the total ion chromatogram of the spiked solution of the aqueous nail polish sample, Figure 3 the total ion chromatogram of the spiked solution of the oily nail polish sample, Figure 2 , Figure 3 which mainly reflects the specificity of the method for the sample.

[0068] (4) Detection:

[0069] Precisely inject 1 μL and inject it into the gas chromatography-mass spectrometer to obtain the chromatographic peak area of the sample;

[0070] Qualitative screening: Take the test sample solution and the standard series solution and measure them under the same analytical conditions. If chromatographic peaks of the quantitative ions and qualitative ions appear in the test solution, the retention time of the characteristic ion peak of the tested component is consistent with the corresponding retention time of the standard series solution, and the maximum deviation of the relative abundance ratio of the selected qualitative ions from the relative abundance ratio of the qualitative ions of the standard solution of the corresponding concentration does not exceed the provisions of Table 3, then it can be determined that the corresponding test component exists in the sample.

[0071] Table 3 Maximum allowable deviation of the relative abundance ratio of ions during qualitative determination

[0072] Ion relative abundance (k) k＞50％ 50％≥k＞20％ 20％≥k＞10％ k≤10％ Maximum allowable deviation ±20％ ±25％ ±30％ ±50％

[0073] Quantitative determination: Take the standard working solution and measure it successively. Using the series concentrations of the tested components as the abscissa and the peak areas of the tested components as the ordinate, perform linear regression to establish the standard curve. Take the test solution for measurement, substitute the chromatographic peak area of the corresponding quantitative ion into the linear regression equation, and calculate the content of each component in the sample.

[0074] 2. Methodology investigations such as specificity, repeatability, accuracy, detection limit, and quantitation limit were carried out on the detection methods for 23 volatile organic compounds.

[0075] The specific investigation methods are as follows:

[0076] (1) Selection of pretreatment conditions

[0077] Selection of extraction method: Considering the special type of the nail polish matrix, it is easy to solidify and the target substances are highly volatile. The pretreatment time should be minimized and the pretreatment method should be simplified. The headspace injection method has poor repeatability, so the direct extraction method is adopted.

[0078] (2) Selection of extraction solvent

[0079] Five extraction solvents, namely methanol, ethanol, acetone, ethyl acetate, and n-hexane, were investigated. Among them, methanol and ethanol had better dispersion effects on nail polish than n-hexane. However, for water-based nail polish, there was no clear supernatant after centrifugation, and it was very difficult to filter with a membrane filter. The sample extract was extremely sticky to the injection needle, resulting in direct damage to the injection needle during injection; after dissolving the sample, acetone was similar to methanol and ethanol, and no clear supernatant could be obtained, and it had relatively high toxicity; ethyl acetate had the best dispersion effect on nail polish, but considering that ethyl acetate could completely dissolve oil-based nail polish, direct injection would cause greater damage to the chromatographic column; n-hexane could not completely disperse the nail polish, which could avoid excessive introduction of matrix causing chromatographic column loss and interfering with the target substance. Through the investigation of the recovery rate, the extraction recovery rate of n-hexane for all target components could reach over 80%, and finally n-hexane was selected as the extraction solvent.

[0080] (3) Investigation of extraction methods

[0081] The following extraction methods were compared: Method 1: The sample was added with n-hexane for dispersion, vortexed, ultrasonically dissolved for 10 min, and centrifuged at 5000 r for 5 min; Method 2: The sample was added with n-hexane for dispersion, vortexed for 5 min, and filtered through a membrane filter; Method 3: The sample was added with n-hexane for dispersion, vortexed for 5 min, and centrifuged at 5000 r / min for 10 min. Among them, both ultrasonic dissolution and membrane filtration would lead to a decrease in the recovery of the target substance (Methods 1 and 2). Method 3 had a better recovery rate and was more convenient to operate. Finally, Method 3 was selected as the sample pretreatment method.

[0082] (4) Investigation of chromatographic columns

[0083] Two types of chromatographic columns with DB-1 and DB-WAX packings were selected. The DB-WAX chromatographic column had a better resolution for xylene, and the 60 m length could effectively separate meta / para-xylene. Therefore, a 60 m length DB-WAX capillary chromatographic column was selected as the analytical column. Two domestic brand chromatographic columns, Dima and Zhongke Antai, were investigated. Both brand chromatographic columns could meet the determination requirements. The Dima chromatographic column had a better resolution, but most of the peak shapes had a little tailing; the Zhongke Antai brand chromatographic column had a sharp and symmetrical peak shape and was better for compounds with a relatively late retention time. Therefore, both domestic brand chromatographic columns could effectively separate the target substances, and domestic chromatographic columns could also replace imported chromatographic columns, improving the universality of the method.

[0084] (5) Linear range and spiked recovery experiment

[0085] In this experiment, nail polishes of three matrix types, namely oil-based nail polish, water-based nail polish, and nail glue, were selected for the spike recovery experiment. The peak areas of the quantitative ion pairs were recorded and the standard curve of peak area versus concentration was plotted. The linear correlation coefficient r ≥ 0.99. The mixed standard series concentration curves were prepared according to the above method, and the spike recovery experiments at three concentrations of low, medium, and high were carried out. The mathematical equations and linear ranges of the calibration curves are shown in Table 4, and the recovery results of each matrix are shown in Tables 5 - 7.

[0086] Table 4 Linear Relationship, Correlation Coefficient, and Linear Range

[0087]

[0088]

[0089] Table 5 Determination Results of the Recovery Rate of Water-based Nail Polish

[0090]

[0091]

[0092]

[0093] Table 6 Determination Results of the Recovery Rate of Oil-based Nail Polish

[0094]

[0095]

[0096] Table 7 Determination Results of the Recovery Rate of Nail Glue

[0097]

[0098]

[0099]

[0100] (6) Detection Limit and Quantification Limit

[0101] Take the reference substance solution and dilute it to an appropriate mass concentration with n-hexane. The injection volume at a signal-to-noise ratio of 10:1 is the quantification limit, and the injection volume at a signal-to-noise ratio of 3:1 is the detection limit.

[0102] Results: Under the above chromatographic conditions, the detection limits, quantification limits, sampling amounts, and the lowest detection concentrations and quantification concentrations of 23 components in this method are shown in Table 8 below.

[0103] Table 8 Detection Limit, Quantification Limit, Detection Concentration, and Quantification Concentration

[0104]

[0105]

[0106] (7) Precision

[0107] Take the std3 concentration control solution and conduct tests according to the above detection method. Continuously measure 6 times to examine the precision of the determination of each component. The results show that the RSD% are all less than 3%. The results are shown in Table 9 below.

[0108] Table 9 Results of Repeatability Experiment

[0109]

[0110]

[0111] (8) Stability

[0112] Take the std3 standard solution and inject samples at certain time intervals for determination. Record the chromatogram and calculate the RSD% of the peak area. The calculation results are shown in Table 10.

[0113] Table 10 Results of Stability Test

[0114]

[0115]

[0116] The 23 components have good linearity within the concentration range shown in Table 4, and the correlation coefficients can all reach above 0.999. The spiked recoveries of the 23 components are between 80.0% and 114.0%. The relative standard deviation of repeatability is RSD% all less than 10%, meeting the technical requirements in the Cosmetics Safety and Technical Specifications.

[0117] The method of this application can effectively detect a variety of harmful substances including 12 kinds of raw materials prohibited in cosmetics, and at the same time covers 11 substances with potential risks although there are no clear limit regulations, ensuring the safety and compliance of nail polish products. Secondly, compared with traditional methods, this application is only optimized for the characteristics of nail polish, avoiding the errors and inconveniences that may be brought by general methods. Most importantly, the sample preparation process is simple and fast, greatly improving the detection efficiency, reducing the uncertainty factors brought by manual operation, and ensuring the accuracy and reliability of the data. These series of characteristics make the method of this application an ideal choice for the detection of volatile organic compounds in nail polish products, not only simplifying the laboratory operation process, but also providing strong technical support for product quality control.

[0118] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry, characterized in that: The following steps are involved: (1) Pre-treating a nail polish sample to obtain a test solution; (2) Weigh the corresponding mass of the reference substance to prepare a single standard stock solution; then measure the single standard stock solutions, mix them, add hexane to dilute and make up to the mark to prepare a mixed standard solution; take the mixed standard solution separately and dilute it in a gradient to prepare a series of standard solutions; (3) Take the test solution and the corresponding standard solution and measure them under the same test conditions. If the test solution shows chromatographic peaks of quantitative ions and qualitative ions, the retention time of the characteristic ion peak of the measured component is consistent with the retention time of the standard solution, and the maximum deviation of the relative abundance ratio of the selected qualitative ion and the relative abundance ratio of the qualitative ion of the standard solution of equivalent concentration should not exceed the corresponding value, then it can be determined that the corresponding test component exists in the nail polish sample; (4) taking the standard solutions and measuring them in sequence, with the concentration series of the component to be measured as the abscissa and the peak area of ​​the component to be measured as the ordinate, performing linear regression to establish a standard curve; (5) Take the test solution for determination, substitute the corresponding quantitative ion chromatogram peak area into the linear regression equation, and calculate the content of each component in the nail polish sample.

2. The method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry according to claim 1, characterized in that: In step (3), the relative abundance ratio of the ions is represented by k: When k>50%, the maximum allowable deviation is ±20%; When 50% ≥ k > 20%, the maximum allowable deviation is ±25%; When 20% ≥ k > 10%, the maximum allowable deviation is ±30%; When k≤10%, the maximum allowable deviation is ±50%.

3. The method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry according to claim 1, characterized in that: In step (2), the steps of preparing the standard solution are: accurately pipetting an appropriate amount of the mixed standard solution, diluting it with hexane to form a series of standard solutions with concentrations of 0.05 μg / mL, 0.1 μg / mL, 0.5 μg / mL, 1.0 μg / mL, 2.0 μg / mL, and 3.0 μg / mL for carbon tetrachloride, trichloroethylene, chloroform, tetrachloroethylene, and α-chlorotoluene, respectively; and 1,1-dichloroethane, 1,2-dichloroethylene, 1,2-dichloroethane, cumene, propylbenzene, and styrene, respectively. There are a series of standard solutions with concentrations of 0.1μg / mL, 0.2μg / mL, 1.0μg / mL, 2.0μg / mL, 3.0μg / mL, and 5.0μg / mL; there are a series of standard solutions with concentrations of 0.2μg / mL, 1.0μg / mL, 2.0μg / mL, 3.0μg / mL, and 5.0μg / mL for tetrahydrofuran, dichloromethane, benzene, toluene, ethylbenzene, p-xylene, m-xylene, o-xylene, nitrobenzene, 2-nitrotoluene, 3-nitrotoluene, and 4-nitrotoluene, respectively.

4. The method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry according to claim 1, characterized in that: The conditions of the gas chromatography-mass spectrometry instrument are: The chromatographic conditions are: Chromatographic column: packed column; Carrier gas: high purity helium; flow rate: 1.5mL / min; Program temperature rise: initial temperature 50°C, hold for 3 min, increase to 110°C at 10°C / min, increase to 230°C at 15°C / min, hold for 5 min; Direct injection; injection port temperature: 210°C; injection volume: 1 μL; split ratio: 20:1; The mass spectrometry conditions were: Ion source type: EI; ion source temperature: 230°C; quadrupole temperature: 150°C; mass spectrometer interface temperature: 230°C; Scan mode: SIM, monitoring 23 volatile organic compound fragment ions.

5. The method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry according to claim 4, characterized in that: The filler chromatographic column is selected from one of AE.PEG-20M, DB-1, and DB-WAX.

6. The method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry according to claim 5, characterized in that: The size of the AE.PEG-20M chromatographic column is 60m×0.50μm×0.25mm.

7. The method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry according to claim 1, characterized in that: The specific process of step (1) is: accurately weigh the nail polish sample into a stoppered centrifuge tube, accurately add the extraction solvent, vortex and shake, and take the supernatant as the test solution.

8. The method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry according to claim 7, characterized in that: The usage ratio of the nail polish sample to the extraction solvent is 0.5 g:3 mL.

9. The method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry according to claim 7, characterized in that: The extraction solvent is selected from one of methanol, ethanol, acetone, ethyl acetate and n-hexane.

10. The method for detecting 23 volatile organic compounds in nail polish by gas chromatography-mass spectrometry according to claim 7, characterized in that: The vortexing time is 5 min; or The vortex shaking was followed by centrifugation, with a centrifugal speed of 5000 r / min and a centrifugal time of 10 min.

Images