Table of Content

22 July 2023, Volume 53 Issue 7 Previous Issue    Next Issue

Basic research

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Study on the inf luence of KCl on the evolution of foam of an anionic surfactant Qiang Xuefeng, Zhang Li, Zheng Bin, Hou Qianqian, Yan Kun 2023, 53 (7):  733-741.  doi: 10.3969/j.issn.2097-2806.2023.07.001 Abstract ( 208 )   HTML ( 18 )   PDF (1991KB) ( 491 )   Foams are widely used in many fields, such as food, cosmetics, medicine, and mineral flotation. The addition of inorganic salts to ionic surfactants will affect the adsorption of surfactants at the air-liquid interface and the solubility of surfactants in solution, thus influencing the evolution of foams. At present, the influences of salts on the evolution of foams of ionic surfactants are still not clear. In this work, the influence of potassium chloride （KCl） on the evolution of foam of sodium dodecyl sulfate （SDS） in the low concentration range was systematically studied. It was found that, when the concentrations of salt and surfactant were both low, the stability of the foam prepared was similar to that without salt, in which the foam was stabilized by surfactant molecules; when the concentrations of salt and surfactant were both increased and their concentrations were close to each other, the salt promoted the adsorption and crystallization of surfactant molecules at the air-liquid interface due to electrostatic interaction, making the stability of foam better than that of pure surfactant, in which the foam was stabilized by inorganic-salt enhanced surfactant molecules; when the salt concentration was slightly higher than the surfactant concentration, the surfactant crystal particles adsorbed on the network of foam, and the local crystals destroyed the liquid film of foam, thus making the foam unstable, in which the foam was stabilized by surfactant molecules under the interference of surfactant crystals; when the salt concentration was further increased, the surfactant crystal particles completely covered on the air-liquid interface of foam, and ultra-stable Pickering foam was obtained by forming solid particle barrier. This research work might have important theoretical guiding significance for further exploring the evolution theory of foams stabilized by surfactant crystal particles and their applications in related fields. Figures and Tables | References | Related Articles | Metrics

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Synthesis and properties of novel surfactants containing naphthalimide and alkyl segments Xing Huanyu, Jia Lihua, Zhao Zhenlong, Yang Rui, Guo Xiangfeng 2023, 53 (7):  742-747.  doi: 10.3969/j.issn.2097-2806.2023.07.002 Abstract ( 143 )   HTML ( 11 )   PDF (1660KB) ( 166 )   A series of novel cationic quaternary ammonium surfactants （CnNDA, n=10, 12, 14 and 16） were designed and synthesized, whose structure had both naphthalimide and long hydrocarbon chain as hydrophobic moieties. Their structures were characterized by FT-IR, 1H NMR, 13C NMR and ESI-MS, and all the synthesized compounds were target products. The surface activity, micellization behavior, foaming ability, foam stability and antibacterial properties were tested. The results showed that, CnNDA showed excellent surface activity and foaming properties. When the carbon number of hydrocarbon chain was increased from 10 to16, the cmc decreased from 1.01 to 0.026 mmol/L; the foam volume of 10 mL aqueous solution of 0.10 g/L C14NDA was 28 mL at 0 min and 26.5 mL at 5 min, and the half-life was 16 h. In addition, CnNDA showed excellent antibacterial activities against E. coli and S. aureus, and the minimum bactericidal mass concentrations for C16NDA were 3.0 and 1.2 μg/mL, respectively. The results of 1H NMR of C12NDA in DMSO-d6 revealed that, the chemical shift of amide proton shifted to the low field by 0.13 with the concentration increased from 3.0 mmol/L to 9.0 mmol/L, indicative of the formation of hydrogen bond by the amido groups. From the fluorescence spectra of different concentrations of C16NDA, it could be found that the fluorescence intensity was decreased and the emission peak was red-shifted by 2 nm when the concentration exceeded cmc, indicative of the π-π stacking between naphthalimide segments. The excellent properties of CnNDA were mainly attributed to the hydrophobic interactions from naphthalimide segments and long alkyl chains, π-π stacking of the adjacent naphthalimide segments, hydrogen bonding of amides groups, and electrostatic interactions. Therefore, they might have potential applications in foam and bactericidal fields. Figures and Tables | References | Related Articles | Metrics

Lecture of science and technology

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Scientific foundations of hair and scalp care （Ⅶ） The causes of hair graying and the methods to make white hair turn black Fang Chengge, Ma Ling, Chen Timson, Chang Kuan, Wang Jing 2023, 53 (7):  748-756.  doi: 10.3969/j.issn.2097-2806.2023.07.003 Abstract ( 234 )   HTML ( 25 )   PDF (1824KB) ( 706 )   With the trend of hair graying becoming younger, hair color has increasingly become a focus of public attention. However, currently, the exact cause of hair graying is still unclear. Herein, starting from the synthetic pathway of melanin, previous research on the mechanism of hair graying was reviewed and two recognized pathways were introduced. The application potential of natural products to delay hair graying was also introduced, and several natural black substances such as graphene oxide and polydopamine in the research of hair dying were listed. This review might provide a reference for the development and application of non-toxic and harmless black dyes and hair-graying-prevention products. Figures and Tables | References | Related Articles | Metrics

Development and application

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The protection mechanism of multi-herb extract CAP against exogenous cutaneous stimulation Zhou Lidan, Lu Yina, Yang Jifeng, Shi Xuemei, Xiong Yue, Zhang Lei 2023, 53 (7):  757-764.  doi: 10.3969/j.issn.2097-2806.2023.07.004 Abstract ( 160 )   HTML ( 11 )   PDF (1807KB) ( 406 )   The skin contains a myriad of immune cells and acts as the first line of defense system against the external environment both as a physical and immune barrier. The cutaneous immune system begins to work even before birth and continuously evolves throughout the lifetime to achieve optimal function by adapting to environmental cues. This study explored the potential mechanism of multi-herb extract CAP against exogenous cutaneous stimulation and discussed the key modulators that drove productive immune responses in skin epidermis and dermal layer immune cells, including keratinocytes, monocytes, and mast cells. Also, a three-dimensional （3D） reconstructed human epidermis model （EpiKutis） was used to perform relevant assays. CAP reduced the expressions of thymic stromal lymphopoietin （TSLP）, interleukin-8 （IL-8）, prostaglandin E2 （PGE-2）, interleukin-6 （IL-6）, and tumor necrosis factor-alpha （TNF-α） that were increased by exogenous stimuli in keratinocytes, 3D EpiKutis, THP-1- derived cells or mast cells. Furthermore, CAP dose-dependently promoted filaggrin level which was decreased by poly （I:C） and LPS induction. These results suggest that CAP might have regulatory functions on keratinocytes, monocytes, and mast cells, which play important roles on the sense, initial and primary stages of the skin inflammatory reactions, respectively. Figures and Tables | References | Related Articles | Metrics

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Synthesis and properties of alkyl polyglucoside sulfosuccinate salts with different degrees of esterification Zhou Yuan, Yang Xiuquan, Zhang Jun, Bai Liang, Wu Zhiyu 2023, 53 (7):  765-772.  doi: 10.3969/j.issn.2097-2806.2023.07.005 Abstract ( 120 )   HTML ( 3 )   PDF (1295KB) ( 116 )   Four products of alkyl polyglucoside sulfosuccinates （APGSS） with different degrees of esterification were synthesized by two-step method. The synthesis conditions of APGSS with different degrees of esterification were optimized by investigating the influences of reaction time and molar ratio on the yields of APGSS. In addition, the foaming properties, emulsifying properties and wetting properties of APGSS with different degrees of esterification were investigated. The results showed that, the foaming properties of APGSS decreased with the increase of esterification degree both in distilled water and hard water, and the foam stability thereof was better than that of alkyl polyglucoside （APG）; the emulsifying performance of all APGSS for soybean oil was better than that for liquid paraffin. With the increase of the degree of esterification, the wetting ability gradually decreased. Figures and Tables | References | Related Articles | Metrics

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Optimization and mechanisms of low-temperature demulsifier for produced fluid with light crude oil Tian Shujie, Gao Wei 2023, 53 (7):  773-780.  doi: 10.3969/j.issn.2097-2806.2023.07.006 Abstract ( 112 )   HTML ( 2 )   PDF (2014KB) ( 284 )   The produced fluid with light crude oil from low-permeability oil field has a big problem in demulsification. Conventional demulsifiers have poor demulsification effect at low temperature （<60 ℃）. In this work, the simulated emulsion was prepared according to the produced fluid of an oil field. The demulsification effect of different types of demulsifiers and the microdynamic characteristics of the emulsion were studied by bottle test and stability analyzer, and the best formula of low-temperature demulsifier was selected; the viscoelasticity and interfacial tension of oil-water interface, and the dynamic adsorption law of the demulsifier at oil-water interface were studied by using an interfacial rheometer, and the action mechanism of low-temperature demulsifier was revealed. Finally, the demulsification effects of different types of demulsifiers at low temperature were analyzed from the perspectives of emulsion dehydration rate, adhesion degree and demulsifier mass concentration. It might provide a theoretical and field-application basis for the research and development of low-temperature demulsification technology for the produced fluid from low-permeability oilfield. Figures and Tables | References | Related Articles | Metrics

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Syntheses of ZnO nanoparticles and their degradation activities on tetracycline hydrochloride Zhang Zhenyang, He Yunyang 2023, 53 (7):  781-788.  doi: 10.3969/j.issn.2097-2806.2023.07.007 Abstract ( 117 )   HTML ( 4 )   PDF (1372KB) ( 122 )   The zinc oxide （ZnO） nanomaterials grafted with C-O functional groups were synthesized by sol-gel, co-precipitation and hydrothermal methods, respectively. The phase purity, organic functional groups and UV absorption capacity were characterized by X-ray powder diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR） and ultraviolet-visible spectrophotometry （UV-vis）. The photocatalytic activities of ZnO nanoparticles synthesized by the three methods were compared using tetracycline hydrochloride as the target of degradation. All the three preparation methods were successful to obtain the ZnO nanomaterials grafted with C-O functional groups. The results of FTIR showed that the samples had no organic functional groups except for C-O functional group. UV-vis diffuse reflectance spectra showed that the products had strong absorption ability to ultraviolet light and weak absorption ability to visible light and could degrade tetracycline hydrochloride. Photocatalytic experiments showed that the best pH value for degradation of tetracycline hydrochloride was 13, the best catalyst dosage was 1 g/L, and the best concentration of tetracycline hydrochloride was 20 mg/L. The impurity level of C-O functional group played an important role in the photocatalytic degradation of tetracycline hydrochloride. Figures and Tables | References | Related Articles | Metrics

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Effect of disinfectants on cell adhesion activity of recombinant type Ⅲ humanized collagen Li Yitong, Sun Yanyan, Qiao Shaojun, Hou Lili, Li Manqin, Yu Yufeng 2023, 53 (7):  789-895.  doi: 10.3969/j.issn.2097-2806.2023.07.008 Abstract ( 125 )   HTML ( 11 )   PDF (1459KB) ( 203 )   The disinfectants available for facial injectable fillers include 75% ethanol, iodine-containing and surfactant-based disinfectants. There is a lack of research on whether the use of various skin disinfectants influences the activity of recombinant type Ⅲ humanized collagen （rhCol Ⅲ）. The toxicity of 75% ethanol, iodophor disinfectant, chlorhexidine gluconate, benzalkonium chloride, and benzalkonium bromide on cells and the cell adhesion activity of rhCol Ⅲ were investigated by CCK8 experiments to predict the effect of disinfectant on collagen activity during facial fillers, in order to provide guidance for clinical application. The results show that all disinfectants have cytotoxicity to NIH/3T3 mouse embryonic fibroblasts and HFB human skin fibroblasts, and the comparative results rank as chlorhexidine gluconate Figures and Tables | References | Related Articles | Metrics

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Stabilizers screening method development for liquid detergent protease Wang Xuejiao, Du Lijuan, Xu Yuanxi 2023, 53 (7):  796-801.  doi: 10.3969/j.issn.2097-2806.2023.07.009 Abstract ( 128 )   HTML ( 8 )   PDF (1107KB) ( 219 )   Enzyme is a kind of important ingredient of most liquid laundry detergent. Protease will autolyze and hydrolyze other enzymes in the liquid. By adding protease stabilizers, the activity of protease is inhibited temporarily, and the shelf life will be prolonged. There are already two commercialized stabilizers in the market, but they could not be used widely due to patent protection. Therefore, to develop other efficient stabilizers is very important for the users. The conventional verification test of stabilizers takes a very long time, so it is not suitable for high-throughput screening. Here this paper developed a simple and efficient screening method based on the principle that stabilizer is a reversible inhibitor. Firstly, the protease hydrolysis reaction of p-nitrophenyl acetate （p-NPA） was used to quantify the candidates’ inhibition ratio on protease, and then verified their stability efficiency in detergents. In addition, lipase can be used as an indicator to further shorten the experiment period. By this way, a variety of substances were evaluated and compared. As a result, 2, 6-difluoropyridine-3-boronic acid is found to be the most efficient one among the reported stabilizers, and 4-（alkylsulfonyl）phenylboronic acid may be also suitable as stabilizers. Finally, there is a positive moderate linear correlation between the protease inhibition ratio and the lipase residual rate in the protease-containing detergents, independent of protease species. The results indicate that this method is suitable for high-throughput screening of protease stabilizers and may be helpful for the development of detergent enzymes. Figures and Tables | References | Related Articles | Metrics

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On-site and rapid electrochemical method for chloramphenicol detection in facial masks Wang Min, Li Mengyue, Li Xiaoyi, Liu Qi, Zhao Hua, Zhao Fengnian 2023, 53 (7):  802-807.  doi: 10.3969/j.issn.2097-2806.2023.07.010 Abstract ( 103 )   HTML ( 3 )   PDF (1521KB) ( 192 )   A portable electrochemical sensor based on gold nanoparticles has been developed for the on-site and rapid detection of chloramphenicol in facial masks. Herein, gold nanoparticles were electrochemically deposited on the surface of the portable and disposable screen-printed electrode with a deposition potential of -0.6 V and a deposition time of 20 s. Results show that the electrocatalytic performance of the chloramphenicol electrochemical sensor modified with gold nanoparticles is significantly enhanced compared with the bare electrode. The pH of the buffer solution was optimized and different concentrations of chloramphenicol were detected under optimal conditions. Results show that when the concentration of chloramphenicol is in the range of 0.02-0.5 mmol/L, the peak current signal is linearly related to the concentration of chloramphenicol, with the limit of detection of 0.005 mmol/L. In order to further evaluate the feasibility of this method, this paper took the commercially available facial masks as the real samples for the recovery experiment. Results show that the recoveries of chloramphenicol at the three spiked levels are from 106.01% to 110.59%, and the relative standard deviation is less than 3.66% （n=3）. Adopting the hand-held electrochemical workstation equipped with Bluetooth, the corresponding analysis data can be received wirelessly in real time on a smartphone, which provides a new research idea for the on-site and rapid detection of chloramphenicol in facial masks. Figures and Tables | References | Related Articles | Metrics

Reviews

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Research progress of cyclodextrin encapsulation technology and its application on cosmetic ingredients Zhang Wanping, Gai Houchen, Zhang Dongmei, Jiang Wen, Zhu Guangyong 2023, 53 (7):  808-815.  doi: 10.3969/j.issn.2097-2806.2023.07.011 Abstract ( 377 )   HTML ( 14 )   PDF (1868KB) ( 186 )   Cyclodextrins are cyclic oligosaccharides that are widely used to improve the performance of bioactive compounds by encapsulation, such as food additives and ingredients or pharmaceutical compounds. Currently, cosmetic industry is constantly striving for better efficacy based on safety. However, the problems of poor water solubility and oxidative decomposition for many active ingredients have greatly limited their development in cosmetic products. Cyclodextrins can protect these compounds against light and oxidative degradation and provide host-guest supramolecular complexes having controlled release properties by molecular encapsulation, enhancing the water solubility and bioavailability. Cyclodextrins are green, non-toxic and degradable and can be used as a suitable delivery vehicle in cosmetics and many other fields. Therefore, the technology by using cyclodextrin as a carrier has also received a lot of attention in the cosmetic field. In recent years, flavonoids and polyphenols have received much attention in the cosmetic industry because of their good whitening and antioxidant effects. Essential oils have also drawn much attention from consumers. In this review, the preparation of cyclodextrin inclusion complexes was introduced, as well as their characterization and their application on many cosmetic ingredients such as polyphenols, flavonoids and essential oils. Figures and Tables | References | Related Articles | Metrics

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Scientific evaluation methods for soothing cosmetics efficacy Feng Faqing, Li Jing 2023, 53 (7):  816-825.  doi: 10.3969/j.issn.2097-2806.2023.07.012 Abstract ( 402 )   HTML ( 33 )   PDF (1015KB) ( 491 )   Under the influence of factors such as the aggravation of environmental pollution and changes in skincare and beauty habits, skin irritation occurs more frequently. Starting from the symptoms perceived by consumers, which mainly include erythema, itching, burning sensation, tightness, dryness, pain and other skin irritation states, this article reviews the possible mechanism and process, and sorts out the efficacy evaluation methods. At present, a variety of evaluation methods applied to food, medicine, clinical efficacy research and other fields have been reported, while there are few related reviews on soothing cosmetics efficacy. In this article, on the basis of the mechanism of triggering the skin irritation states, we review various evaluation methods on three pathways of skin inflammatory response, skin barrier and neural response, which are divided into laboratory tests （including biochemical methods, cell biological methods, three-dimensional recombinant skin models, animal and the animal alternative experiment methods）, consumer use testing and human efficacy evaluation tests （including subjective, semi-subjective and objective instrumental evaluation methods）, and overview their applications in efficacy evaluation of cosmetics, expecting to provide new ideas of scientific efficacy evaluation for soothing cosmetics. Figures and Tables | References | Related Articles | Metrics

Analytical methods and testing

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Determination of 13 bisphenols and alkylphenols environmental hormones in essential oil cosmetics by UPLC-MS/MS method Liu Zhen, Wang Yumei, Yang Junli, Sun Xiaojie 2023, 53 (7):  826-832.  doi: 10.3969/j.issn.2097-2806.2023.07.013 Abstract ( 105 )   HTML ( 7 )   PDF (1113KB) ( 137 )   Environmental hormone is a kind of substance that can disturb biological endocrine, among which bisphenols and alkylphenols have great potential harm because they are widely used in the manufacture of plastics. At present, there are many researches on the related detection technologies in the fields of environment and food, but there are few reports on high-throughput simultaneous detection of bisphenols and alkylphenols in cosmetics. In order to analyze the migration amount of bisphenols and alkylphenols environmental hormones in cosmetics, an ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） method was developed for the determination of 13 environmental hormones including 9 bisphenols and 4 alkylphenols in essential oil cosmetics. The chromatographic conditions, extraction reagent, dosage and ultrasonic time were optimized, then actual samples were measured with this established method. The essential oil cosmetics were extracted by ultrasonic extraction with 10% ammonium-acetonitrile solution, concentrated by nitrogen blowing, and eluted by gradient elution of methanol and water on an Agilent Poroshell EC-C18 column （3.0 mm×150 mm, 2.7 μm）. The 13 analytes were scanned by electrospray ion source negative ion mode （ESI-）, and analyzed with multiple response monitoring model （MRM）. The results show that there is a good linear relationship for 13 kinds of bisphenols and alkylphenols environmental hormones in the certain mass concentration range of 0.25-200 ng/mL, with the linear correlation coefficients greater than 0.99. The limits of detection （LOD） and the limits of quantitation （LOQ） of each substance are 0.000 375-0.007 5 µg/g and 0.001 25-0.025 µg/g, respectively. The average recoveries at three spiked levels of 0.025, 0.05 and 0.25 µg/g range from 81.8% to 113.4% with the intra-day precision （n=6） of 1.1% to 8.5%, and the inter-day precision （n=18） of 3.5% to 11.5%. The method is established with simple pretreatment, good recovery and high stability, which has achieved effective chromatographic separation of 13 target substances. It is suitable for simultaneous quantitative and qualitative analysis of 13 bisphenols and alkylphenols environmental hormones in essential oil cosmetics. Figures and Tables | References | Related Articles | Metrics

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Determination of 29 anti-allergy drugs by UPLC-MS/MS in cosmetics Zheng Jiaxin, Jia Changping, Zhang Shanshan 2023, 53 (7):  833-840.  doi: 10.3969/j.issn.2097-2806.2023.07.014 Abstract ( 92 )   HTML ( 6 )   PDF (1025KB) ( 113 )   The study aims to develop an ultra high performance liquid chromatography-tandem mass spectrometry method for the determination of 29 anti-allergy drugs in cosmetics. The samples were extracted by ultrasonic machine with acetonitrile, and the separation was executed on a column using the mobile phase consisting of 0.1% ammonium hydroxide （A） and 0.1% ammonium hydroxide methanol solution （B）. The analysis was performed using a positive electrospray ion source in multiple reaction monitoring （MRM） mode. The result show that the linear relationship of the 29 anti-allergy drugs in the linear range is good, and the correlation coefficient is greater than 0.997. The detection limits are between 0.4-12.9 ng/g, and the average recovery rate is in the range of 80.9%-115.9%, with RSD within 0.3%-14.8%. 2 Batches of positive samples are detected within 10 batches of the samples, cyproheptadine and cyproheptadine impurity 1 are found in 1 batch, and cimetidine is found in 1 batch. The established method is simple, selective, sensitive and accurate, and can be used for the determination of anti-allergy drugs in cosmetics. Figures and Tables | References | Related Articles | Metrics

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Simultaneous determination of nine effective components in Polygonum Multif lorum Fangtuoyufa Jinghuaye by HPLC-QAMS Liu Ying, Lin Min, Dai Sirui 2023, 53 (7):  841-848.  doi: 10.3969/j.issn.2097-2806.2023.07.015 Abstract ( 117 )   HTML ( 7 )   PDF (1142KB) ( 321 )   The study aimed to establish an HPLC-QAMS method for simultaneous quantitation of nine effective components in Polygonum Multiflorum Fangtuoyufa Jinghuaye, and to verify the feasibility and accuracy of the method. Quercitrin was used as the reference substance and methanol-0.1% phosphoric acid was used as the mobile phase. The contents of emodin, physcion, myricitrin, quercitrin, myricetin, quercetin, kaempferol, amentoflavone and hinokiflavone in 12 batches of Polygonum Multiflorum Fangtuoyufa Jinghuaye were determined by external standard method and HPLC-QAMS method, respectively, and the difference between the results of the two methods was compared to verify the serviceability of HPLC-QAMS method. The results show that the linear ranges of the nine components are good, the correlation coefficients are greater than 0.999, the limits of detection （LOD） are 0.027-0.151 µg/mL, and the limits of quantification are 0.076-0.449 µg/mL. The relative correlation factors are 0.753 7, 0.836 9, 1.019 2, 2.991 3, 1.687 5, 2.236 9, 1.096 3 and 1.249 3 for emodin, physcion, myricitrin, myricetin, quercetin, kaempferol, amentoflavone and hinokiflayone, respectively. There is no significant difference in the content of 9 components in Polygonum Multiflorum Fangtuoyufa Jinghuaye determined by the two methods （P>0.05）. The relative correlation factors established with quercitrin as the internal reference substance have good reproducibility. The HPLC-QAMS method can be used for the quality evaluation of nine effective components in Polygonum Multiflorum Fangtuoyufa Jinghuaye. Figures and Tables | References | Related Articles | Metrics

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Determination of 42 glucocorticoids beyond the national standard method in cosmetics by solid phase extraction-liquid chromatography tandem mass spectrometry Ma Liangbo, Sun Yu, Zhu Guifang, Lu Jiayi, Xu Yan, Liu Tao 2023, 53 (7):  849-856.  doi: 10.3969/j.issn.2097-2806.2023.07.016 Abstract ( 121 )   HTML ( 6 )   PDF (1240KB) ( 186 )   A solid phase extraction （SPE）-ultra performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） method was developed for the determination of 42 glucocorticoids in cosmetics, in addition to the existing standard of 50 glucocorticoids. After the samples were dispersed, extracted and purified, 42 glucocorticoids were determined by using UPLC Shim-pack XR-ODSIII C18 （2.0 mm×150 mm, 2.2 μm） chromatographic column, 0.1% （V/V） acetic acid acetonitrile solution and 0.1% （V/V） acetic acid aqueous solution as the mobile phase at the mode of electrospray ionization （ESI） and multiple reaction monitoring （MRM）. A total of 42 hormones have good linearity, and the correlation coefficients are above 0.99. For water, emulsion and cream substrates, the limit of detection （LOD） is 0.03 μg/g and the limit of quantification （LOQ） is 0.1 μg/g. The average recoveries of three levels and six parallel tests range from 67.6%-112.5% for water, emulsion and cream substrates. At present, two positive samples with these 42 glucocorticoid components have been screened, which provides a more comprehensive method for monitoring the illegal addition of glucocorticoids in cosmetics. Figures and Tables | References | Related Articles | Metrics