Method for identifying authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS) method

Abstract

The invention discloses a method for identifying the authenticity of cosmetics based on a gas chromatography-mass spectrometry (GC-MS) method, which is used for identifying the authenticity of the cosmetics on the basis of qualitative analysis and quantitative analysis. Firstly, layer-by-layer progressive identification is carried out from chromatographic features to mass spectrum features, the principle of'whether all features are all or not 'is followed, as long as one feature cannot be compared, the feature is judged as counterfeit, and then a measured value of the quantitative test raw material content is compared with a raw material content value in a genuine product or a raw material component content in a cosmetic filing system, so that the content of the raw material in the genuine product is determined. If the error range is + / -10%, the product is genuine, otherwise, the product is fake. The method improves the accuracy of cosmetic identification, solves the problems that qualitative analysis technologies such as single appearance identification and pure spectrum identification are easily interfered by impurities and fluorescence, the sensitivity is poor, and cosmetics with complex components cannot be identified, solves the technical problem of cosmetic identification, fills the technical blank of counterfeit cosmetic identification, and has wide application prospects. The method is suitable for true and false identification of components in all cosmetics.

Description

Technical Field

[0001] The invention relates to a qualitative and quantitative method for identifying the authenticity of cosmetics based on a gas chromatography-mass spectrometry (GC-MS) method, and belongs to the technical field of cosmetics identification. Background Art

[0002] Cosmetics identification is a complex process. Due to the different product labels of different countries, brands, and manufacturers, it is difficult to judge cosmetics. The means of identifying the authenticity of cosmetics are mainly appearance, such as: approval number, production license number, implementation standard number, shelf life, manufacturer and place of origin, product ingredients and functional descriptions, Chinese labels and customs certificates of imported cosmetics, whether the labeled weight is consistent with the actual weight, whether the product packaging is shoddy, etc. There are very few laboratory inspection means or methods for the authenticity identification of cosmetic ingredients. It is difficult to keep up with the times to identify cosmetics only from the appearance. In addition, there is no standard to refer to. The invention of counterfeit cosmetic ingredient identification technology is imminent, which can fill the technical gap in cosmetic ingredient identification.

[0003] The invention patent application (application number 201610528708.3) discloses a method for identifying the quality of powder cosmetics using energy dispersive X-ray fluorescence spectroscopy fingerprint recognition technology; the invention patent application (application number 202010223243.7) discloses a method for identifying cosmetics based on infrared spectroscopy technology; the invention patent application (application number 202011103124.4) discloses a Raman spectroscopy-based non-destructive identification method for the authenticity of cosmetics; the invention patent application (202310605923.9) discloses a method for classifying and identifying oily cosmetic raw materials based on GC-MS technology. However, these methods have limitations. For example, energy dispersive X-ray fluorescence analysis (EDXRF) can only be used for identification through characteristic elements, and it is difficult to distinguish similar substances such as isomers. Infrared spectroscopy technology has poor sensitivity because it measures the absorption of double frequency and combined frequency. It generally requires the detection content to be greater than 1%, and can only measure substances containing infrared absorption functional groups, and cannot measure substances without infrared absorption functional groups. Raman spectroscopy technology is a spectral measurement method, which is easily interfered by impurities and fluorescence, has low sensitivity, and cannot identify cosmetics with complex components. GC-IMS technology can only analyze volatile substances, and cannot identify non-volatile substances. Euclidean distance has obvious disadvantages. It treats the differences between different attributes of the sample (i.e., each indicator or each variable star) as the same, which sometimes cannot meet actual requirements. In addition, there are other GC-MS methods for determining harmful substances in cosmetics, which are often complicated in pretreatment and require extraction, purification and other steps.

[0004] The present invention is based on qualitative analysis and quantitative analysis to identify the authenticity of cosmetic ingredients. First, qualitative identification is carried out step by step from chromatographic characteristics to mass spectrometry characteristics, following the principle of "one negative, all negative", that is, if a sample has one feature that cannot be matched, it will be judged as a counterfeit. Then, the measured value of the raw material content in the quantitative test is compared with the raw material content value in the authentic product or the raw material component content in the cosmetics filing system. If the error range is within ±10%, it is a genuine product, otherwise it is a counterfeit. It has high accuracy and is suitable for the authenticity identification of ingredients in all cosmetics. Summary of the invention

[0005] The method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS) can meet the needs of identifying trace ingredients (content less than 0.1% (w / w)) in cosmetics, and is suitable for authenticating all cosmetics and ingredients.

[0006] In order to solve the above technical problems, the technical solutions adopted by the present invention are as follows:

[0007] A method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS), wherein the sample spectrum is obtained by testing the cosmetics through GC-MS after pretreatment;

[0008] Cosmetics confirmed by the manufacturer are authentic cosmetics. The graph obtained by GC-MS testing with authentic cosmetics as reference and under the same pre-treatment and testing conditions as the cosmetics to be tested is called the reference spectrum.

[0009] Compare the sample spectrum with the reference spectrum, first conduct qualitative analysis of the ingredients in the cosmetics, then conduct quantitative analysis, to achieve the purpose of identifying the authenticity of cosmetics, and at the same time can meet the requirements of the identification of trace ingredients in cosmetics (content less than 0.1% (w / w)), suitable for the authenticity identification of all cosmetics and ingredients;

[0010] The authentic cosmetics in this application mainly come from various types of cosmetics that are subject to district, city or provincial level supervision spot checks / risk monitoring (spot check task notice) and enterprise-commissioned inspections (commissioned contracts) conducted by this unit, and have passed the sample confirmation of the production enterprise (sample confirmation notice).

[0011] Cosmetics to be tested: mainly from samples purchased from the market, etc.

[0012] Qualitative analysis:

[0013] Comparing the sample spectrum with the GC-MS spectrum of the authentic cosmetics includes the following steps:

[0014] The first step is to define the gas chromatography-mass spectrometry GC-MS spectrum of the authentic cosmetics as the reference spectrum;

[0015] The second step is to place the sample spectrum and the reference spectrum in a set of horizontal and vertical coordinates, and observe whether the overall peak shape of the chromatograms of the two GC-MS spectra (the GC-MS spectra of the authentic cosmetics and the GC-MS spectra of the cosmetics to be tested) is consistent. The overall peak shape includes the position and number of peaks. If they are inconsistent, it is judged to be a counterfeit. If they are consistent, proceed to the third step;

[0016] The third step is to compare the retention times of the peaks in the two GC-MS spectra (error time ± 0.5min) to see if they are consistent. If they are inconsistent, it is judged to be a fake. If they are consistent, proceed to the fourth step.

[0017] The fourth step is to compare the relative responses of each peak by integrating and calculating each peak (error range 80%-120%). If they are inconsistent, it is judged to be a fake. If they are consistent, proceed to the fifth step.

[0018] The fifth step is to observe whether the mass spectra (m / z) of each peak type are consistent one by one. If they are inconsistent, it is judged to be a fake. If they are consistent, proceed to the sixth step;

[0019] The sixth step is to compare the relative responses of the characteristic ions of the mass spectra corresponding to each peak (error range 80%-120%). If they are inconsistent, it is judged as a fake. If they are consistent, it will enter quantitative analysis;

[0020] Quantitative analysis:

[0021] Quantitative method for testing authentic products: prepare a series of standard solutions of substances to be quantitatively analyzed, conduct GC-MS testing under the same pretreatment and testing conditions as for the cosmetics to be tested, and draw a standard curve with the concentration of the standard series solutions as the horizontal axis and the peak area as the vertical axis (i.e., external standard method); by comparing the sample spectrum, the reference spectrum and the standard curve, obtain the contents a and b of the substances to be quantitatively analyzed in the cosmetics to be tested and the authentic cosmetics, respectively, and compare a and b. If the difference is within ±10% (90%-110%), it is authentic, otherwise it is a counterfeit.

[0022] When preparing a standard solution, you need to purchase the standard product of the raw material.

[0023] The content b of the substance that needs to be quantitatively analyzed in the above-mentioned authentic product can also be obtained by the following method: Cosmetics registration system formula query comparison method: The data source of the specific ingredient content of cosmetic raw materials can refer to the "National Drug Smart Supervision Platform Comprehensive Supervision Portal" (ie, the cosmetics registration system) for the content of each raw material in the product formula. This system covers the registration information of all cosmetics produced, operated and sold in China. By comparing the content a of the substance that needs to be quantitatively analyzed in the measured sample with the ingredient content in the cosmetics registration system, if the difference is within ±10% (90%-110%), it is a genuine product, otherwise it is a counterfeit.

[0024] When identifying the main components and trace components, pre-treatment techniques such as increasing or decreasing the weight of the test sample, concentration, dilution, etc. can be used to assist in avoiding errors in the test results caused by too low or too high content.

[0025] The present invention solves for the first time the problem that qualitative analysis techniques such as simple spectral identification in cosmetics are easily interfered by impurities and fluorescence, have poor sensitivity, and cannot identify cosmetics with complex components, thereby solving the technical difficulties in cosmetics identification.

[0026] The sample spectra are compared with the GC-MS of the authentic cosmetics by quantitative and qualitative comparison, wherein the qualitative comparison is to first compare the chromatograms of the sample spectra and the GC-MS of the authentic cosmetics to see if they are consistent. If they are consistent, then compare the mass spectra. If the mass spectra and the chromatograms are consistent, then proceed to the next step. If there is at least one inconsistency between the mass spectra and the chromatograms, then it is a counterfeit (fake cosmetics). The quantitative comparison is to compare the GC-MS measured value with the component content value in the authentic cosmetics. If the error range is within ±10% (90%-110%), then it is authentic, otherwise it is a counterfeit.

[0027] The present invention is based on qualitative analysis and quantitative analysis to identify the authenticity of cosmetics. First, qualitative identification is carried out step by step from chromatographic characteristics to mass spectrometry characteristics, following the principle of "one negative, all negative", that is, as long as one feature of the sample does not match, it will be judged as a counterfeit, and then the measured value of the raw material content in the quantitative test is compared with the raw material content value in the authentic product or the raw material component content in the cosmetics filing system. If the error range is within ±10%, it is a genuine product, otherwise it is a counterfeit.

[0028] In order to improve the detection accuracy, the cosmetics to be tested are pre-treated as follows:

[0029] According to the different dosage forms of cosmetics, there are 11 dosage forms, including creams, liquids, gels, powders, blocks, muds, wax bases, sprays, aerosols, patches / films (including substrates), freeze-dried powders and freeze-dried tablets;

[0030] For liquid, spray and aerosol dosage forms: Place the sample and sodium chloride directly into the headspace vial for GC-MS injection;

[0031] For dosage forms such as creams, gels, powders, blocks, muds, wax-based products, patches / films (including substrates), lyophilized powders and lyophilized tablets: extract the sample with a solvent using ultrasonic extraction, take the supernatant after centrifugation, purify it with a solid phase extraction column, and then filter it with a 0.45μm filter membrane. The resulting liquid is used for GC-MS injection, where the solvent is a 1:1 mixture of methanol and dichloromethane.

[0032] In order to improve the detection accuracy and convenience, the GC-MS test conditions are as follows:

[0033] (1) For volatile cosmetics with a boiling point ≤ 150°C (such as liquids, sprays, aerosols and other dosage forms):

[0034] Headspace-gas chromatography-mass spectrometry conditions:

[0035] Chromatographic conditions: the chromatographic column is a 5%-phenyl-methyl polysiloxane column with a length of 30 m, an inner diameter of 250 μm, and a film thickness of 1.4 μm; the heating program is as follows: the initial temperature is 50° C. and maintained for 3 min, then the temperature is increased to 70° C. and maintained for 1 min at a heating rate of 10° C. / min, then the temperature is increased to 160° C. and maintained for 1 min at a rate of 12° C. / min, and then operated for 2 min; the carrier gas is helium (purity>99.999%), the carrier gas flow rate is 1.0 mL / min, the injection port temperature is 280° C., the injection volume is 1.0 mL, and the injection mode is splitless injection;

[0036] Headspace conditions: equilibrium temperature 80°C, injection loop temperature 90°C, transfer line temperature 100°C, headspace equilibrium time 30 min, ring leveling time 0.05 min, pressurization time 0.2 min, injection time 0.5 min;

[0037] Mass spectrometry conditions: interface temperature of 180°C, ion source of EI source, ion source temperature of 230°C, ionization energy of 70 eV, solvent delay of 0.5 min, acquisition mode of scanning mode (SCAN).

[0038] (2) For cosmetics with a boiling point greater than 150°C (such as creams, gels, powders, blocks, muds, and wax-based dosage forms):

[0039] Gas chromatography-mass spectrometry conditions:

[0040] Reference chromatographic conditions: the chromatographic column is a 5%-phenyl-methyl polysiloxane column, with a length of 30m, an inner diameter of 250μm, and a film thickness of 1.4μm; the temperature program is: 45℃ for 1min, rising to 70℃ at 10℃ / min, rising to 120℃ at 20℃ / min, rising to 200℃ at 10℃ / min, and rising to 280℃ at 20℃ / min; the carrier gas is helium (purity>99.999%), the carrier gas flow rate is 1.0mL / min, the injection port temperature is 280℃, the injection volume is 1μL, and the injection method is splitless injection;

[0041] Reference mass spectrometry conditions: interface temperature of 180°C, ion source of EI source, ion source temperature of 230°C, ionization energy of 70 eV, solvent delay of 1.5 min, and acquisition mode of scanning mode (SCAN).

[0042] In the third step of the above qualitative analysis, the allowed error of the retention time is ±0.5min, excluding the endpoint value.

[0043] In the fourth step of the above qualitative analysis, the relative response of the peak has an allowable error of 80%-120%, excluding the endpoint value.

[0044] In the sixth step of the above qualitative analysis, the allowable error of the relative response of the characteristic ions is 80%-120%, excluding the endpoint value.

[0045] In the second to sixth steps of the above qualitative analysis, if the relative deviation between the sample spectrum and the reference spectrum is less than 20%, they are considered consistent; otherwise, they are considered inconsistent.

[0046] The above “consistency”, unless otherwise specified, refers to a relative deviation of ±20%, that is, consistency within an error range of 80-120% (excluding endpoint values), otherwise it is “inconsistent”.

[0047] As one specific implementation scheme, the above method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS) comprises the following steps:

[0048] 1) Establish a gas chromatography-mass spectrometry (GC-MS) database of authentic cosmetics as a benchmark spectral library;

[0049] 2) Obtaining a chromatogram-mass spectrum: Obtaining a gas chromatography-mass spectrometer (GC-MS) of the cosmetic to be tested, which is called a sample spectrum;

[0050] 3) Retrieving a reference spectrum: Retrieving the gas chromatography-mass spectrometry (GC-MS) of the authentic cosmetics corresponding to the cosmetics to be tested from the reference spectrum library as the reference spectrum (hereinafter referred to as the chromatogram of the authentic cosmetics as the reference spectrum);

[0051] 4) Identification and comparison: Compare the sample spectrum with the reference spectrum, first conduct a qualitative analysis of the ingredients in the cosmetics, and then conduct a quantitative analysis to identify the authenticity of the cosmetics.

[0052] As mentioned above, qualitative analysis: first compare the chromatograms of the sample spectrum and the reference spectrum to see if they are consistent. If they are consistent, then compare the mass spectrum. If the mass spectrum and the chromatogram are consistent, then enter the quantitative analysis. If there is at least one inconsistency between the mass spectrum and the chromatogram, it is a counterfeit; quantitative analysis: compare the measured value of the raw material content based on the quantitative test with the raw material ingredient content in the cosmetics registration system or the measured value of the authentic product. If the error range is within ±10%, it is authentic, otherwise it is a counterfeit.

[0053] The authenticity of the cosmetics to be tested is judged by comparing the results of the triple identification of chromatogram, mass spectrum and quantitative content analysis.

[0054] According to the classification of the dosage form of cosmetic products, the present invention can simultaneously identify the cosmetic ingredients by qualitative analysis and quantitative analysis through simple pre-treatment, and identify the authenticity of cosmetics by the ingredients of cosmetics. In terms of qualitative and quantitative analysis, in addition to manual comparison analysis, the quantitative analysis can also be performed after setting using Agilent data quantitative analysis software "MassHunter", which can achieve rapid comparison.

[0055] In addition, the mass spectrum database refers to the Agilent NIST mass spectrum reference library for mass spectrum library search, which can identify unknown compounds from MS spectra.

[0056] The present invention is based on qualitative analysis and quantitative analysis. In qualitative analysis, based on the principle that the peak type, peak retention time, peak relative response, mass spectrum and relative response of mass spectrum characteristic ions of the same substance are consistent, the effective ingredients in different types of cosmetics are identified for the first time by gas chromatography-mass spectrometry, and the peak type, peak retention time, peak relative response, mass spectrum and relative response of mass spectrum characteristic ions of the main components in the total ion flow chromatogram are compared in turn, and then the measured value of the raw material content in the quantitative test is compared with the raw material content value in the authentic product or the raw material component content in the cosmetics filing system. If the error range is within ±10%, it is a genuine product, otherwise it is a counterfeit. It not only solves the technical problem that qualitative analysis technologies such as element identification, specific absorption functional group identification, and spectral identification are prone to false positives, but also improves the accuracy of identification and solves the problem of being easily interfered by other components.

[0057] The technologies not mentioned in the present invention are all referred to the prior art.

[0058] The present invention is a method for identifying the authenticity of cosmetics based on the gas chromatography-mass spectrometry (GC-MS) method, and performs authenticity identification on cosmetics based on qualitative analysis and quantitative analysis. First, the method is progressively identified from chromatographic features to mass spectrum features, and the principle of "one negative, all negative" is followed. That is, as long as one feature of the sample does not match, it will be judged as a counterfeit. Then, the measured value of the raw material content in the quantitative test is compared with the raw material content value in the genuine product or the raw material component content in the cosmetics filing system. If the error range is within ±10%, it is a genuine product, otherwise it is a counterfeit, which improves the accuracy of cosmetic identification, solves the technical difficulty of single identification from the appearance, solves the problem that qualitative analysis technologies such as simple spectral identification in cosmetics are easily affected by impurities and fluorescence interference, have poor sensitivity, and cannot identify complex component cosmetics, solves the technical difficulties in cosmetic identification, fills the technical gap in counterfeit cosmetic identification, and can be applied to the authenticity identification of ingredients in all cosmetics. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1.1The present invention is a flow chart of a qualitative analysis method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS);

[0060] Figure 1.2 The present invention is a flow chart of a quantitative method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS);

[0061] Figure 2.1 Qualitative analysis diagram of counterfeit products in Example 1 of the present invention (inconsistent overall peak shape);

[0062] Figure 2.2 Qualitative analysis diagram of counterfeit products in Example 1 of the present invention (inconsistent retention times);

[0063] Figure 2.3 Qualitative analysis diagram of counterfeit products in Example 1 of the present invention (inconsistent peak relative response);

[0064] Figure 2.4 Qualitative analysis diagram of counterfeit products in Example 1 of the present invention (inconsistent mass spectra);

[0065] Figure 2.5 Qualitative analysis diagram of counterfeit products in Example 1 of the present invention (inconsistent relative response of mass spectrometry ions);

[0066] Figure 2.6 Schematic diagram of quantitative analysis of counterfeit products in Example 1 of the present invention;

[0067] Figure 3.1 Qualitative analysis diagram of the authentic product in Example 2 of the present invention (the overall peak shape is consistent);

[0068] Figure 3.2 Qualitative analysis diagram of the authentic product in Example 2 of the present invention (consistent retention time);

[0069] Figure 3.3 Qualitative analysis diagram of the authentic product in Example 2 of the present invention (peak relative response is consistent);

[0070] Figure 3.4 Qualitative analysis diagram of the authentic product in Example 2 of the present invention (consistent with the mass spectrum);

[0071] Figure 3.5 Illustration of the qualitative analysis of the authentic product in Example 2 of the present invention (the relative response of mass spectrometry ions is consistent);

[0072] Figure 3.6 Schematic diagram of quantitative analysis of authentic products in Example 2 of the present invention;

[0073] Figure 4.1 False positive qualitative analysis diagram in Example 3 of the present invention (the chromatograms are consistent, but the relative responses are inconsistent);

[0074] Figure 4.2Schematic diagram of the false positive qualitative analysis in Example 3 of the present invention (the chromatogram and relative response are consistent, but the mass spectrum is inconsistent). DETAILED DESCRIPTION

[0075] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

[0076] Example 1 Counterfeit

[0077] A method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS), according to Figure 1.1 and 1.2 Follow these steps:

[0078] (1) Sample acquisition

[0079] Acquisition of authentic products: The cosmetics are perfumes, and the authentic products come from the Nanjing Cosmetics Supervision and Random Inspection Task, and the sample confirmation notice is mailed, and the sample is confirmed by the manufacturer (XX Perfume Co., Ltd.) as the cosmetics produced by this company.

[0080] Test samples: purchased from the market.

[0081] (2) Sample pretreatment

[0082] The product is perfume. Directly weigh 2g of sample and 1g of sodium chloride into a headspace bottle, shake well, and directly inject the sample into the headspace.

[0083] Preparation of aqueous solution for calibration curve: Purchase the standard product of the raw material, prepare a series of concentration gradients (5, 10, 30, 50, 70, 80, 90, 100 μg), and inject the sample after preparation according to the above pretreatment method.

[0084] (3) Testing

[0085] The product is a perfume, which is a volatile cosmetic. The test of the authentic product, sample and standard curve is carried out according to the following conditions:

[0086] Headspace-gas chromatography-mass spectrometry conditions:

[0087] Reference chromatographic conditions: the chromatographic column is a 5%-phenyl-methylpolysiloxane column with a length of 30m, an inner diameter of 250μm, and a film thickness of 1.4μm; the heating program: the initial temperature is 50°C and maintained for 3min, the temperature is increased to 70°C at a heating rate of 10°C / min and maintained for 1min, the temperature is increased to 160°C at a rate of 12°C / min and maintained for 1min, and then operated for 2min; the carrier gas is helium (purity>99.999%), the carrier gas flow rate is 1.0mL / min, the injection port temperature is 280°C, the injection volume is 1.0mL, and the injection mode is splitless injection.

[0088] Reference headspace conditions: equilibrium temperature of 80 °C, injection loop temperature of 90 °C, transfer line temperature of 100 °C, headspace equilibrium time of 30 min, ring leveling time of 0.05 min, pressurization time of 0.2 min, and injection time of 0.5 min.

[0089] Reference mass spectrometry conditions: interface temperature of 180°C, ion source of EI source, ion source temperature of 230°C, ionization energy of 70 eV, solvent delay of 0.5 min, and acquisition mode of scanning mode (SCAN).

[0090] (4) Qualitative analysis

[0091] Comparing the sample spectrum with the gas chromatography-mass spectrometry (GC-MS) spectrum of the authentic cosmetics includes the following steps:

[0092] The first step is to use Agilent's MassHunter to open the baseline spectrum and sample chromatogram at the same time, and place them in a set of horizontal and vertical coordinates for overall observation.

[0093] The second step is to observe whether the overall peak shape (peak position and number) of the chromatograms of the two GC-MS spectra are consistent. Figure 2.1 The red chromatogram is the benchmark chromatogram, and the black one is the sample chromatogram. It can be seen that the overall peak type is: the benchmark chromatogram contains peak 2, but no peak 1, peak 3, and peak 4, while the sample chromatogram contains peaks 1, peak 3, and peak 4, but no peak 2 in the benchmark chromatogram. The overall peak types of the two are inconsistent; the overall number of peaks: the number of main peaks in the benchmark chromatogram is 1, while the number of peaks in the sample chromatogram is more than 1. Therefore, the product is determined to be a counterfeit, and there is no need for subsequent identification, but for the sake of ease of understanding, continue with the subsequent steps.

[0094] The third step is to compare the retention time of each peak type in the two chromatograms (error time ± 0.5min). Take Peak 1 in the chromatogram as an example. Figure 2.2 In the figure, the dotted line is the reference retention time in the benchmark chromatogram, but no typical chromatogram (i.e., the red curve) is seen at the retention time of 3.6 min, so the product is determined to be a counterfeit.

[0095] The fourth step is to compare the relative responses of each peak by integrating and calculating each peak (error range 80%-120%). Figure 2.3 As shown, at a retention time of 3.6 min, each ion peak was integrated, the response of the highest ion peak 88.0 was taken as the base peak (100%), and the response ratio errors of the other ion peaks (58.0, 57.0 and 43.0) were calculated to be 119.1%, 136.1% and 62.2%, respectively. The response ratio errors of two ion peaks were not in the range of 80%-120%, so the product was determined to be a counterfeit.

[0096] The fifth step is to observe whether the mass spectra (m / z) of each peak type are consistent. Figure 2.4 As shown, there are 5 mass ions in the standard mass spectrum (corresponding to serial numbers 1-5), while there are only 4 mass ions in the sample mass spectrum (corresponding to serial numbers ad). The number of mass spectra in the sample mass spectrum and the standard mass spectrum is inconsistent; and the overall shape height distribution of the mass spectrum is also inconsistent. For example, in the standard mass spectrum, the mass ion (88.0) is the highest response mass ion, while in the sample mass spectrum, the mass ion (43.0) is the highest response mass ion. The highest response mass ions of the two are inconsistent, so the product is judged to be a counterfeit.

[0097] The sixth step is to compare the relative responses of the characteristic ions of the mass spectra of each peak (error range 80%-120%). Figure 2.5 As shown, in the standard mass spectrum, the highest response ion 88.0 is selected as the base peak (100%), and the error range of the relative response ratio of the ions (58.0, 57.0 and 43.0) in the standard mass spectrum is 100.0%, while in the sample mass spectrum, the error range of the relative response ratio of the ion is 136.1% and 62.2%, which exceeds the error judgment range of 80%-120%, so the product is judged to be a counterfeit.

[0098] (5) Quantitative analysis (cosmetics registration system formula query comparison method)

[0099] The substance was found to be polysorbate through mass spectral library retrieval, and the corresponding standard was purchased to prepare a series of standard solutions, and GC-MS test was performed under the same conditions. In Agilent's MassHunter quantitative software, the standard solution and sample data spectra were called, and relevant parameters were edited and set to draw the standard curve ( Figure 2.6 B) and the sample quantitative result was 8.85μg ( Figure 2.6 A), according to the calculation of the content of the raw material in the sample = (measured value / sample weight) × 100%, that is, the content of the raw material = (8.85 μg × 10 -6 / 2g)×100%=0.0004425%, while the content of this raw material in the product formula in the cosmetics registration system is 0.01%, and the error range is not within the range of ±10%, so the product is determined to be a counterfeit.

[0100] In summary, whether it is qualitative or quantitative judgment, this product is a counterfeit.

[0101] 300 samples were tested using the above method, including 168 perfumes, 56 sprays, and 76 aerosols, with an accuracy of 100%.

[0102] If the GC-MS test conditions of this example are replaced with the test conditions of Example 2, the accuracy decreases by 15.6%.

[0103] Example 2 authentic

[0104] A method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS), according to Figure 1.1 and 1.2 Follow these steps:

[0105] (1) Sample acquisition

[0106] Acquisition of authentic products: The cosmetics are XX lipstick, and the authentic products come from the Nanjing cosmetics supervision random inspection task. The sample confirmation notice was mailed, and the sample was confirmed by the manufacturer (XX Cosmetics Co., Ltd.) as a cosmetics produced by this company.

[0107] Test samples: purchased from the market.

[0108] (2) Sample pretreatment

[0109] The product is lipstick, 2g of sample is weighed, and ultrasonic extraction is performed for 30min using methanol / dichloromethane (v / v) = 1:1 (if the sample is not completely dissolved, dichloromethane solution is added as appropriate until all the sample is dissolved), the supernatant is taken after centrifugation, and purified using a solid phase extraction column filled with a mixed silica gel-neutral alumina, and eluted with n-hexane-ethyl acetate (v / v = 1:1), the eluent is collected, concentrated to 1mL, passed through a 0.45μm organic filter membrane, and the liquid is used for GC-MS injection.

[0110] Preparation of aqueous solution for calibration curve: Purchase the standard product of the raw material, prepare a series of concentration gradients (5, 10, 30, 50, 70, 80, 90, 100 μg), and inject the sample after preparation according to the above pretreatment method.

[0111] (3) Testing

[0112] The product is a lipstick, which is not a volatile cosmetic. The test of the authentic product, sample and standard curve is carried out according to the following conditions:

[0113] Gas chromatography-mass spectrometry conditions:

[0114] Reference chromatographic conditions: the chromatographic column is a 5%-phenyl-methylpolysiloxane column with a length of 30m, an inner diameter of 250μm, and a film thickness of 1.4μm; the temperature program is: maintain at 45°C for 1min, increase to 70°C at 10°C / min, increase to 120°C at 20°C / min, increase to 200°C at 10°C / min, and increase to 280°C at 20°C / min; the carrier gas is helium (purity>99.999%), the carrier gas flow rate is 1.0mL / min, the injection port temperature is 280°C, the injection volume is 1μL, and the injection method is splitless injection.

[0115] Reference mass spectrometry conditions: interface temperature of 180°C, ion source of EI source, ion source temperature of 230°C, ionization energy of 70 eV, solvent delay of 1.5 min, and acquisition mode of scanning mode (SCAN).

[0116] (4) Qualitative analysis

[0117] Comparing the sample spectrum with the gas chromatography-mass spectrometry (GC-MS) spectrum of the authentic cosmetics includes the following steps:

[0118] The first step is to use Agilent's MassHunter to open the baseline spectrum and sample chromatogram at the same time, and place them in a set of horizontal and vertical coordinates for overall observation.

[0119] The second step is to observe whether the overall peak shape (peak position and number) of the chromatograms of the two GC-MS spectra are consistent. Figure 3.1 The red chromatogram is the reference chromatogram, and the green one is the sample chromatogram. It can be seen that the overall peak type: the peak positions of the reference chromatogram and the sample chromatogram basically coincide, and the overall peak types of the two are consistent; the overall number of peaks: the number of main peaks in the reference chromatogram and the sample chromatogram are both 2, so the overall peak types are consistent, and subsequent identification is still required.

[0120] The third step is to compare the retention time of each peak type in the two chromatograms (error time ± 0.5min). Take Peak 1 in the chromatogram as an example. Figure 3.2 In the figure, the dotted line is the reference retention time in the benchmark chromatogram. The retention times are all around the reference retention time of 3.56 min, satisfying the retention time error of ±0.5 min. Therefore, the retention is consistent and subsequent identification is still required.

[0121] The fourth step is to compare the relative responses of each peak by integrating and calculating each peak (error range 80%-120%). Figure 3.3 As shown, at the retention time of 3.56 min, each ion peak was integrated, the response of the highest ion peak 88.0 was taken as the base peak (100%), and the response ratio errors of other ion peaks (58.0, 57.0 and 43.0) were calculated to be 100.1%, 99.4% and 99.5%, respectively. The response ratio error range was 80%-120%, so the peak relative response ratios were consistent and subsequent identification was still required.

[0122] The fifth step is to observe whether the mass spectra (m / z) of each peak type are consistent. Figure 3.4 As shown, the number of mass spectra in the standard mass spectrum and the sample mass spectrum is consistent, both have 5 mass spectral ions (corresponding to serial numbers 1-5), the mass spectral ions are also consistent, namely 43.0, 57.0, 58.0, 87.0, and 88.0, and the overall shape height distribution of the mass spectrum is also consistent. Therefore, the mass spectra are consistent and subsequent identification is still required.

[0123] The sixth step is to compare the relative responses of the characteristic ions of the mass spectra of each peak (error range 80%-120%). Figure 3.5 As shown, in the standard mass spectrum, the highest response ion 88.0 is selected as the base peak (100%), and the error range of the relative response ratio of the ions (58.0, 57.0 and 43.0) in the standard mass spectrum is 100.0%, and the error range of the relative response ratio of the ion in the sample mass spectrum is 100.4%, 99.4%, and 99.5%, respectively, which are all within the error judgment range of 80%-120%. Therefore, the mass spectra are consistent and subsequent quantitative identification is still required.

[0124] (5) Quantitative analysis (quantitative method for genuine product testing)

[0125] The substance was found to be polysorbate by searching the mass spectral library, and the corresponding standard was purchased to prepare a series of standard solutions, and then GC-MS tests were performed under the same conditions. In Agilent's MassHunter quantitative software, the standard solution and sample data spectra were called, and the relevant parameters were edited and set. The quantitative results were obtained by drawing the standard curve, such as Figure 3.6 The content of the substance in the authentic product and the sample is 38.89 μg and 35.97 μg, and the ratio of the content of the raw material in the sample to the content of the raw material in the authentic product is 92.5%, which meets the requirement of an error range of ±10% (ie 90%-110%).

[0126] In summary, based on qualitative and quantitative judgments, this product is authentic.

[0127] 300 samples were tested using the above method, including 103 creams, 32 gels, 48 ​​powders, 26 lipsticks, 59 lipsticks, and 32 mud masks, with an accuracy of 100%.

[0128] If the GC-MS test conditions of this example are replaced with the test conditions of Example 1, the accuracy decreases by 24.3%.

[0129] Example 3 False Positive

[0130] For the false positive example, the sample acquisition, sample pretreatment, testing, and quantitative analysis are all consistent with the steps of the authentic product (Example 2) and the counterfeit product (Example 1). There will be no false positives in this part. False positives only exist in the qualitative analysis part, so this false positive case only enumerates examples of the qualitative analysis part.

[0131] like Figure 4.1 As shown in A, the retention time of the raw material meets the reference retention time (red vertical line) ± 0.5min, but Figure 4.1The relative responses of the chromatogram in B are 41.1%, 78.1%, and 18.6%, respectively, all of which are not within the error range of 80-120%. Although the retention times are consistent, the peak relative response ratios are not within the error range, so this type is a false positive.

[0132] like Figure 4.2 As shown in , the peak type, retention time, and peak relative response of the raw material are all within the error range, but the mass spectrum of the sample is inconsistent with the standard mass spectrum. For example, m / z 207.0 is the base peak in the sample mass spectrum, but m / z149.0 is the base peak in the standard mass spectrum; and the number and size of mass spectra in the sample mass spectrum are not completely consistent with the standard mass spectrum, such as m / z150.0, 238.0, etc. Although the peak type, retention time, and peak relative response are all within the error range, the mass spectra are inconsistent, so this type is a false positive.

Claims

1. A method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS), characterized in that: The graph obtained by GC-MS testing of the tested cosmetics after pretreatment is called the sample spectrum; Cosmetics confirmed by the manufacturer are authentic cosmetics. The graph obtained by GC-MS testing with authentic cosmetics as reference and under the same pre-treatment and testing conditions as the cosmetics to be tested is called the reference spectrum. Compare the sample spectrum with the reference spectrum, first conduct qualitative analysis on the ingredients in the cosmetics, then conduct quantitative analysis, to achieve the purpose of identifying the authenticity of cosmetics, and at the same time can meet the identification of trace ingredients in cosmetics, suitable for the authenticity identification of all cosmetics and ingredients; Qualitative analysis: Comparing the sample spectrum with the GC-MS spectrum of the authentic cosmetics includes the following steps: The first step is to define the gas chromatography-mass spectrometry GC-MS spectrum of the authentic cosmetics as the reference spectrum; The second step is to place the sample spectrum and the reference spectrum in a set of horizontal and vertical coordinates to observe whether the overall peak shape of the chromatograms of the two GC-MS spectra is consistent. The overall peak shape includes the position and number of peaks. If not, it is judged as a fake. If consistent, proceed to the third step; The third step is to compare the retention times of the peaks in the two GC-MS spectra to see if they are consistent. If not, it is judged to be a fake. If consistent, proceed to the fourth step. The fourth step is to compare the relative responses of each peak by integrating and calculating each peak. If they are inconsistent, it is judged to be a fake. If they are consistent, proceed to the fifth step. Step 5: Observe the mass spectra of each peak type one by one to see if their m / z are consistent. If not, it is judged to be a fake. If consistent, proceed to step 6. The sixth step is to compare the relative responses of the characteristic ions of the mass spectra corresponding to each peak. If they are inconsistent, it is judged as a fake. If they are consistent, it will enter the quantitative analysis; Quantitative analysis: Quantitative method for genuine product testing: prepare a series of standard solutions of the substances to be quantitatively analyzed, conduct GC-MS testing under the same pretreatment and testing conditions as the cosmetics to be tested, and draw a standard curve with the concentration of the standard series solutions as the abscissa and the peak area as the ordinate; By comparing the sample spectrum, the reference spectrum and the standard curve, the contents a and b of the substances to be quantitatively analyzed in the tested cosmetics and the authentic cosmetics are obtained respectively. By comparing a and b, if the difference is within ±10%, it is authentic, otherwise it is a counterfeit.

2. The method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS) according to claim 1, characterized in that: The cosmetics to be tested are pre-treated as follows: According to the different dosage forms of cosmetics, they are divided into creams, liquids, gels, powders, blocks, muds, wax-based, sprays, aerosols, patches / films, freeze-dried powders and freeze-dried tablets; For liquids, sprays and aerosols: Place sample and sodium chloride directly into headspace vial for GC-MS injection; For dosage forms such as creams, gels, powders, blocks, muds, wax-based, patches / films, lyophilized powders and lyophilized tablets: extract the sample with a solvent using ultrasonic extraction, take the supernatant after centrifugation, purify it with a solid phase extraction column, and then filter it with a 0.45μm filter membrane. The resulting liquid is used for GC-MS injection, where the solvent is a 1:1 mixture of methanol and dichloromethane.

3. The method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS) according to claim 1 or 2, characterized in that: GC-MS test conditions are as follows: For volatile cosmetics with a boiling point ≤150°C: Headspace-gas chromatography-mass spectrometry conditions: Chromatographic conditions: the chromatographic column is a 5%-phenyl-methyl polysiloxane column with a length of 30m, an inner diameter of 250μm, and a film thickness of 1.4μm; the heating program is as follows: the initial temperature is 50°C and maintained for 3min, then the temperature is increased to 70°C at a heating rate of 10°C / min and maintained for 1min, then the temperature is increased to 160°C at a rate of 12°C / min and maintained for 1min, and then the temperature is run for 2min; the carrier gas is helium, the carrier gas flow rate is 1.0mL / min, the injection port temperature is 280°C, the injection volume is 1.0mL, and the injection mode is splitless injection; Headspace conditions: equilibrium temperature 80°C, injection loop temperature 90°C, transfer line temperature 100°C, headspace equilibrium time 30 min, ring leveling time 0.05 min, pressurization time 0.2 min, injection time 0.5 min; Mass spectrometry conditions: interface temperature was 180 °C, ion source was EI source, ion source temperature was 230 °C, ionization energy was 70 eV, solvent delay was 0.5 min, and acquisition mode was scan mode.

4. The method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS) according to claim 1 or 2, characterized in that: GC-MS test conditions are as follows: For cosmetics with boiling point >150℃: Gas chromatography-mass spectrometry conditions: Reference chromatographic conditions: the chromatographic column is a 5%-phenyl-methyl polysiloxane column, with a length of 30m, an inner diameter of 250μm, and a film thickness of 1.4μm; the temperature program is: 45℃ for 1min, rising to 70℃ at 10℃ / min, rising to 120℃ at 20℃ / min, rising to 200℃ at 10℃ / min, and rising to 280℃ at 20℃ / min; the carrier gas is helium, the carrier gas flow rate is 1.0mL / min, the injection port temperature is 280℃, the injection volume is 1μL, and the injection method is splitless injection; Reference mass spectrometry conditions: interface temperature of 180 °C, ion source of EI source, ion source temperature of 230 °C, ionization energy of 70 eV, solvent delay of 1.5 min, and acquisition mode of scanning mode.

5. The method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry GC-MS according to claim 1 or 2, characterized in that: In the third step, the allowed error of retention time is ±0.5min.

6. The method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry GC-MS according to claim 1 or 2, characterized in that: In the fourth step, the relative response of the peak is allowed to have an error of 80%-120%.

7. The method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry GC-MS according to claim 1 or 2, characterized in that: In the sixth step, the allowable error of the characteristic ion relative response is 80%-120%.

8. The method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry GC-MS according to claim 1 or 2, characterized in that: In steps 2 to 6, if the relative deviation between the sample spectrum and the reference spectrum is less than 20%, they are considered consistent; Otherwise, it is considered inconsistent.

9. The method for identifying the authenticity of cosmetics based on gas chromatography-mass spectrometry (GC-MS) according to claim 1 or 2, characterized in that: The steps include: 1) Establish a gas chromatography-mass spectrometry (GC-MS) database of authentic cosmetics as a benchmark spectral library; 2) Obtaining a chromatogram-mass spectrum: Obtaining a gas chromatography-mass spectrometer (GC-MS) of the cosmetic to be tested, which is called a sample spectrum; 3) Retrieving a reference spectrum: Retrieving a gas chromatography-mass spectrometry (GC-MS) spectrum of the authentic cosmetics corresponding to the cosmetics to be tested from the reference spectrum library as a reference spectrum; 4) Identification and comparison: Compare the sample spectrum with the reference spectrum, first conduct a qualitative analysis of the ingredients in the cosmetics, and then conduct a quantitative analysis to identify the authenticity of the cosmetics.

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