Table of Content

22 September 2021, Volume 51 Issue 9 Previous Issue    Next Issue

Basic research

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Study on the preparation and emulsifying properties of peach seed protein isolate nanoparticles Shen Yongqiang,Sun Yajuan,Yang Cheng,Wang Jing 2021, 51 (9):  809-816.  doi: 10.3969/j.issn.1001-1803.2021.09.001 Abstract ( 285 )   HTML ( 115 )   PDF (2438KB) ( 275 )   Peach seed protein isolate （PSPI） was prepared by alkali extraction with isoelectric precipitation. The composition of the PSPI was determined, and the protein content was approximately 91.2%. When the pH is below the isoelectric point, the particles are positively charged, and conversely, when the pH is above the isoelectric point, the particles are negatively charged. PSPI nanoparticles were prepared by pH-cycling method, and they exhibited excellent stabilization for Pickering emulsions. The size of the particles is around 300 nm, and they aggregate to different degrees with the change of pH. The wettability of PSPI nanoparticles could be adjusted simply by changing the pH of solutions, and the system shows a neutral wettability at pH 2.0 and 8.0. However, when the pH value is 5.0, the particles have strong hydrophobicity. The rheological properties indicate that the emulsion is pseudoplastic fluid with gelatinous properties. At pH 2.0 and 8.0, the emulsions have outstanding stability, and moreover, stable high internal phase Pickering emulsions （HIPPEs） with internal oil phase fraction of 80% and even 87% were obtained. In addition, such HIPPEs have good resistance to ionic strength, which can remain stable at high salt concentration up to 1 mol/L for over 1 month. These findings show that PSPI nanoparticles are green and excellent emulsifier, which have potential applications in food, cosmetic, and petroleum industries. Figures and Tables | References | Related Articles | Metrics

Lecture of science and technology

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Botanical cosmetic ingredients （V）Research and development of plant antioxidants Ren Qianqian,Sun Xu,Wu Hua,Jin Jianming 2021, 51 (9):  817-824.  doi: 10.3969/j.issn.1001-1803.2021.09.002 Abstract ( 685 )   HTML ( 84 )   PDF (1241KB) ( 689 )   Biological oxidation is an energy-producing reaction in the metabolism of living organisms. Under cellular metabolism or extracellular stress, the skin cells continuously produce highly active free radicals and reactive oxygen species. Over-producing these highly active molecules causes cell structure changes, leading to early apoptosis and skin problems. Antioxidants help to improve the antioxidant capacity of the organisms and eliminate the harmful effects of free radicals and reactive oxygen species. Herein, free radicals and reactive oxygen species, oxidative stress, oxidative damage and the skin diseases caused by them, as well as the mechanisms of antioxidant action, have been reviewed. The plant extracts with antioxidant activity have been mainly introduced, including phenols, phenolic acids, flavonoids, stilbenes, procyanidin, carotenoids and vitamins. Among them, phenolic compounds are most important. Most polyphenols exist in conjugated forms and exhibit excellent antioxidant activity. The common structural feature of these natural antioxidants is the presence of phenolic hydroxyl groups or conjugated double bonds. For an antioxidant, the better the antioxidant effect it has, the easier it is to be reduced. The hydroxytyrosol, which is both water- and fat-soluble, has strong antioxidant capacity. The fat-soluble astaxanthin and water-soluble vitamin C also show good antioxidant activity. The antioxidation mechanisms of some plant ingredients have been described to provide reference for the application of plant extracts as antioxidants in cosmetics. Figures and Tables | References | Related Articles | Metrics

Development and application

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Synergistic effect of N, N-dimethyl-9-decenamide and sodium dodecyl sulfate Xu Dekun,Fang Yinjun,Liu Xuefeng 2021, 51 (9):  825-831.  doi: 10.3969/j.issn.1001-1803.2021.09.003 Abstract ( 393 )   HTML ( 19 )   PDF (1478KB) ( 298 )   In order to address the defect of poor water solubility of the non-ionic surfactant N, N-dimethyl-9-decenamide （NADA）, the possible synergistic effect between NADA and anionic surfactant sodium dodecyl sulfate （SDS） was investigated in the binary systems of NADA-SDS. The results show that positive synergistic effects are observed by blending NADA and SDS, leading to an obvious increasing in water solubility of NADA. At 25 ℃, the aqueous solutions of NADA-SDS （where the mass fraction of NADA is 1%） are transparent when the mole fraction of SDS （xS） > 0.05. The efficiency of reducing surface tension is significantly improved by the formation of NADA-SDS hybrid micelles. The minimum critical micelle concentration （cmc, in terms of the total concentration of NADA-SDS） and the maximum critical micelle aggregation number （[Nm]） are obtained at the mole fraction of NADA （xN） = 0.5 as 4.04 mmol/L and 76, respectively. The effectiveness of reducing surface tension of NADA-SDS is remarkably enhanced by the forming of NADA-SDS hybrid adsorption layer. The minimum surface tension at cmc （γcmc） of 28.44 mN/m is achieved at xN = 0.9. Figures and Tables | References | Related Articles | Metrics

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Preparation and performance evaluation of oil soluble viscosity reducer for heavy oil fields in Canada Xiao Sa,Sun Yubao,Wang Shaohua,Wu Chunzhou,Shu Zhan 2021, 51 (9):  832-838.  doi: 10.3969/j.issn.1001-1803.2021.09.004 Abstract ( 288 )   HTML ( 19 )   PDF (1403KB) ( 1876 )   M oilfield in Canada is characterized by low temperature, shallow buried depth, high viscosity of crude oil, less water cut and poor fluidity. Due to the high content of resin and asphaltene, it is very difficult to recover the crude oil by conventional mining method. It is necessary to reduce the viscosity of the crude oil from M oilfield in Canada. Oil soluble viscosity reduction technology has stable viscosity reduction effect on heavy oil and saves the steps of produced fluid demulsification and dehydration. In recent years, the research on oil soluble viscosity reducer at home and abroad has developed rapidly. Due to the great differences in the composition and characteristics of heavy oil in different regions, the adaptability to oil soluble viscosity reducer is different. According to the characteristics of heavy oil in M oilfield, an oil soluble viscosity reducer PH-OV was developed. The results show that the optimum composition of PH-OV is 4% esterified polyether +15% diethylene glycol dibutyl ether +81% aromatic solvent oil. When the dosage of PH-OV is 3%, the viscosity reduction rate can reach 85.2%; when the dosage of PH-OV is more than 5%, the viscosity reduction rate can reach more than 80% within 14-80 ℃. The SEM chart show that the viscosity reducer PH-OV can effectively destroy the aggregation structure of crude oil, disperse resin and asphaltene, inhibit the formation of macromolecular aggregates and reduce viscosity. With the increase of water content of crude oil, the viscosity reduction rate increases. When the water content is 60%, the viscosity reduction rate reaches 98.5%. The viscosity reducer can effectively reduce the yield value of crude oil, and the viscosity reduction performance of crude oil can be stable for more than 168 h. With the increase of viscosity reducer, the yield value of crude oil decreases significantly, which can effectively reduce the initial starting pressure of crude oil. The efficiency of PH-OV assisting cold water flooding can reach 30.03%, which is 12.86% higher than that of cold water flooding. The oil soluble viscosity reducer PH-OV is suitable for cold recovery of heavy oil in M oilfield, and has the potential to effectively enhance oil recovery. Figures and Tables | References | Related Articles | Metrics

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Study on the properties of lauric acid polyglycol ester prepared by regenerating polyethylene glycol from waste crystal-silicon-cutting liquid Wang Zeyun,Chen Hailan,Sun Hong,Wang Jie 2021, 51 (9):  839-843.  doi: 10.3969/j.issn.1001-1803.2021.09.005 Abstract ( 222 )   HTML ( 8 )   PDF (988KB) ( 330 )   Lauric acid polyglycol ester （LAE-R） was synthesized by the reaction of lauric acid with the polyethylene glycol recycled from waste crystal-silicon-cutting liquid. The surface tension （γcmc）, critical micelle concentration （cmc）, wetting power, emulsifying power, foaming performance and detergency were measured, as well as the degreasing rate in a dishwashing detergent. These properties were compared with those of AEO-9 and lauric acid polyglycol ester （LAE-I） which had been synthesized from industrial-grade PEG400 and lauric acid. The results show that LAE-R has high surface activity （γcmc is 28.9 mN/m and cmc is 60.4 mg/L, which are lower than those of LAE-I and AEO-9）. The emulsifying power of LAE-R on diesel oil and soybean oil is similar to that of AEO-9, but slightly lower than that of LAE-I. The wetting power and foaming power of LAE-R are lower than those of LAE-I and AEO-9. Therefore, LAE-R is a low-foam surfactant. LAE-R has the same comprehensive cleaning ability to carbon black cloth and sebum cloth as LAE-I, but its cleaning ability to carbon black cloth is lower than that of AEO-9. The degreasing rate of LAE-R is basically the same as those of LAE-I and AEO-9 during applied in a dishwashing detergent formula, however, LAE-R has a certain competitive advantage in cost performance due to its low raw material cost. Figures and Tables | References | Related Articles | Metrics

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Degradation of sodium dodecyl benzene sulfonate by mechanochemical method Zhao Qingqing,Chen Hongling 2021, 51 (9):  844-851.  doi: 10.3969/j.issn.1001-1803.2021.09.006 Abstract ( 252 )   HTML ( 10 )   PDF (1708KB) ( 205 )   Sodium dodecyl benzene sulfonate （SDBS） is a widely used anionic surfactant in many industrial fields such as printing, washing, textile and building materials. The use of SDBS generates a lot of bubbles to reduce the oxygenation in water, which causes some negative effects and requires degradation treatment. Mechanochemical method is environmentally friendly and efficient for treatment of organic pollutants, which is widely used in soil remediation. At present, the ball milling method is mainly applied to the degradation of halogenated organics. The research on the treatment of surfactants has rarely been reported. In this work, the degradation properties of SDBS which was ball milled with La2O3 and magnetic recyclable Fe3O4 were investigated. Then the degradation of SDBS by the same method was explored in the soil. The chemical structure and properties of SDBS and the degradation products thereof were characterized by FTIR, UV-vis and LC-MS to find out the best experimental parameters. The results show that the best degradation rates of La2O3 and Fe3O4 to SDBS are 93.89% and 85.56%, respectively. The best experimental parameters are as follows: the mass ratio of additives to SDBS is 19:1, the mass ratio of ball to material is 40:1, the ball grinding speed is 500 r/min, and the ball grinding time is 4 h. When the additive is La2O3, 100% Φ 5 mm ball milling beads are used, and when the additive is Fe3O4, 20% Φ 10 mm, 60% Φ 5 mm and 20% Φ 2 mm ball milling beads are used. In the soil, the degradation rates of SDBS by La2O3 and Fe3O4 are 75.35% and 34.88%, respectively. Through UV and IR analysis, it is found that the benzene ring structure is destroyed and -SO3- is oxidized, both indicating that SDBS has been degraded by ball milling treatment. LC-MS analysis shows that the molecular ion peaks of SDBS become weaker and many ion peaks of small organic molecules appear after ball milling, which also demonstrates that SDBS has been degraded by ball milling. Figures and Tables | References | Related Articles | Metrics

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Preparation and tunable structural color of dual-responsive nanogels Ding Hanxue,Li Xueting,Lu Xihua 2021, 51 (9):  852-858.  doi: 10.3969/j.issn.1001-1803.2021.09.007 Abstract ( 225 )   HTML ( 7 )   PDF (1466KB) ( 211 )   A weakly acidic monomer L-N-acryloyl phenylalanine （APhe） was synthesized. Poly（NIPA-co-APhe） copolymer nanogels were synthesized by emulsion precipitation copolymerization of the monomer Aphe with the thermosensitive monomer N-isopropylacrylamide （NIPA）. The structure and morphology of the nanogels prepared were characterized by IR and TEM, respectively. The results show that the particles of nanogels are spherical and monodispersed. The nanogels were also analyzed by particle size analyzer. It is found that the nanogels have good temperature/pH sensitivities. That is, the particle size is gradually decreased with the increase of temperature, and the particle size is first increased and then decreased with the increase of pH. The structural color was characterized by optical fiber spectrometer. It is found that the structural color of the nanogels can be adjusted by varying the monomer ratio and pH value. That is, the particle size is gradually increased with the increase of molar fraction of monomer APhe, and the color is gradually changed from green to blue as the compression degree of the particles is increased. Furthermore, it is important to observe that the Poly（NIPA-co-APhe） nanogels even keep the structural color in the case of undergoing a temperature-induced phase transition. Figures and Tables | References | Related Articles | Metrics

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Study on the effect of a fresh milk cream on facial skin bacterial diversity Ma Xue,Xian Zhiming,Dong Qiang,Zheng Chao,Pan Yao,Zhao Hua 2021, 51 (9):  859-864.  doi: 10.3969/j.issn.1001-1803.2021.09.008 Abstract ( 255 )   HTML ( 17 )   PDF (1393KB) ( 294 )   As the body’s largest organ, skin is the home of billions of microbes and helps protect the host from the external pathogens. The skin microbial barrier can be affected by endogenous factors （skin location, age, gender, and race） and exogenous factors （environment, antibiotics, and cosmetics）. Cosmetics contain complex ingredients, such as preservatives, fragrances, emulsifiers, moisturizers, etc. These substances may affect the skin’s microenvironment. The purpose of this study is to investigate the effects of a cream containing fresh milk on the bacterial diversity of facial skin using high-throughput sequencing technology. A total of 10 subjects were enrolled and they were all females with the average age of 24.1 years old. The subjects used a cream containing fresh milk for 28 days, and the cheek skin microbiological specimens were collected by cotton swabs before and 28 days after the use of the fresh milk cream. DNA was extracted and amplified by PCR, and 16S rRNA high-throughput sequencing was carried out. OTU clustering and species classification annotation were performed to analyze and compare the bacterial community composition, diversity and differences of the facial skin before and after using the fresh milk cream. It is found that after using the fresh milk cream, the alpha diversity parameters including Chao1 and Shannon diversity index of the cheek skin decrease, and the distribution of the samples becomes more concentrated. The species composition at phylum level after using the cream is the same as the baseline, indicating that the use of this cream has little impact on the skin microbial health. However, the proportion of Firmicutes and Actinomycetes in the skin flora of the subjects after using the cream significantly increase, which is mainly caused by the increase of the proportion of Staphylococcus and Propionibacterium, respectively. The Staphylococcus resides in the skin area that is rich in moisture, whereas Propionibacterium plants in the area with abundant sebum content. Additionally, no skin adverse reactions are observed among the subjects, showing that the fresh milk cream is generally well tolerated. Taken this, the study reveals that the fresh milk-containing cream plays an important role in regulating the microecology of the facial skin, and has a prominent moisturizing and nourishing efficacy. Figures and Tables | References | Related Articles | Metrics

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Multiple emulsions in calcium alginate microgels as a delivery system for the encapsulation of different polar nutrients: Preparation and in vitro characterization Huang Juan,Jiang Pingfu,Xie Wenjing,Chen Jianchu,Shi Jianqiang,Hu Xiaojia 2021, 51 (9):  865-873.  doi: 10.3969/j.issn.1001-1803.2021.09.009 Abstract ( 299 )   HTML ( 11 )   PDF (1579KB) ( 372 )   In this study, β-carotene and vitamin C were used as models of different polar nutrients. Regarding the poor stability and low bio-availability of nutrients, multiple emulsions in calcium alginate microgels were prepared to improve the stability and bio-availability of nutrients. Multiple emulsions in calcium alginate microgels were prepared by the improved two-step emulsification and the injection-gelation method. The average particle size of multiple emulsions and microgels are approximately 6-7 μm and 1 000 μm, respectively, and the encapsulation efficiency of the nutrients is higher in microgels than in multiple emulsions. The prepared calcium alginate microgels are spherical orange-red particles. The optical microscope displays that the multiple emulsions have multi-layer structure. There are small droplets of oleogel inside the droplets of the multiple emulsion. The multiple emulsion can be clearly observed on the edge of the calcium alginate microgels. The stability, in vitro dissolution and in vitro digestion were further characterized. The results show that microgels have wider tolerance to pH and sodium ions. In addition, at low pH value, the average particle size of calcium alginate microgels is smaller, showing shrinkage behavior; at high pH value, the average particle size of calcium alginate microgels is larger, showing swelling behavior. The chemical stability of β-carotene and vitamin C can be enhanced by being encapsulated in the multiple emulsions in calcium alginate microgels. After being encapsulated in the multiple emulsions in microgels, the dissolution of β-carotene and vitamin C and the digestion of fatty acids become slower. The higher the concentration of sodium alginate, the slower the dissolution of the nutrients and the digestion of fatty acids. Fat crystallization can hinder the digestion or degradation of fatty acids in multiple emulsions. The in vitro dissolution results show that the behavior of calcium alginate microgels is also influenced by pH, i.e., the dissolution of β-carotene and vitamin C is slower at the pH simulated as gastric acid and is faster at the pH simulated as intestinal conditions. The bio-availability of nutrients is lower in microgels than in multiple emulsions. This study reveals that the second encapsulation by microgels can improve the chemical stability and bio-availability of different polar nutrients and control their release. Figures and Tables | References | Related Articles | Metrics

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Dynamic changes of gene expression induced by long-wave ultraviolet radiation in human dermal fibroblasts Yin Qingfei,Chen Tian 2021, 51 (9):  874-880.  doi: 10.3969/j.issn.1001-1803.2021.09.010 Abstract ( 427 )   HTML ( 13 )   PDF (1808KB) ( 253 )   The dynamic changes of extracellular matrix, cell cycle and senescence-related genes at mRNA level in human primary dermal fibroblasts were studied by irradiated with different cumulative doses of ultraviolet UVA （1-7 days）. The results show that the expression of the collagen genes COL1A2 and COL4A1 is up-regulated at day 1 and decreases at day 3, while the mRNA level of the elastin gene ELN remains unchanged at day 1 and decreases at day 3. The expression of the matrix metalloproteinase genes MMP1 and MMP9 increases significantly at day 5 after UVA irradiation. Further studies show that the cell cycle is arrested in S phase and G2/M phase after 3 and 5 days after UVA irradiation. The expression of cell cycle related gene CDKN2A is down-regulated, and that of TP53 gene is up-regulated at first and then down-regulated. CDKN1A gene is up-regulated, and reaches the highest level at day 3 after UVA irradiation. Compared with the control group, the expression of aging-related genes SIRT1 and HDAC1 is up-regulated at first, then decreases, and increases again. The results show that the changes of cell senescence induced by UVA irradiation is a programmed regulation process, and different groups of genes in fibroblasts show diverse trends of dynamic changes under UVA irradiation. The suitable biomarkers should be selected according to the specific aims in the application of cell senescence model for researching anti-aging effect of cosmetics. Figures and Tables | References | Related Articles | Metrics

Reviews

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Research progress of related factors in oral ulcers Che Biao,Gao Yan,Xiao Lei,Huang Jinlian 2021, 51 (9):  881-889.  doi: 10.3969/j.issn.1001-1803.2021.09.011 Abstract ( 484 )   HTML ( 16 )   PDF (1375KB) ( 316 )   The recent literature has been reviewed from the signal transduction and related factors of oral ulcers to provide theoretical reference for the research and treatment thereof. The pathogenic mechanism of oral ulcers is complex, involving immune abnormalities, trauma, excessive fatigue, hormone changes, vitamin deficiency, genetic factors, etc. Common manifestations include oral candidiasis, recurrent aphthous ulcers, or cancer patients with radiation or drug treatment, which have resulted in mucosal ulcers that greatly affect the life quality of patients. The pathogenic mechanism of oral ulcers involves many inducing factors and signal pathways. The composition and content of factors, such as external signal factors, immune factors of the body, receptor molecules on the cell surface, and intracellular signal transmission, as well as the changes in their related signal pathways, have played different roles in the development and healing process of oral ulcers. In this review, NF-κB and TNF-α have been discussed a lot. This review combines recent reports in the literature, from the aspects of TGF-β, Smad7, FOXO1, TNF-α, IL-17, NO and ROS, JNK, targeted therapy drugs, immune checkpoint inhibitors, etc. Thus the current research progress of related factors and signal pathways in causes and repair mechanisms of oral ulcers has been reviewed. IL-6, IL-8, COX-2, TLRs, Dectine-1, p38 MAPK, etc. are interspersed in relevant introductions. By analyzing the possible connections between them, it is found that a balance between inflammation and tissue repair is needed to promote oral ulcer healing. For example, ROS/NO aggravates inflammation through PGE2, but it promotes cell proliferation and migration through JNK/TGF-β pathway for repair. TNF-α promotes the production of various inflammatory factors by T cells, and yet it promotes the synthesis of collagen and MMPs through the JNK/c-Jun pathway to help tissue repair. Smad7 and IL-17 are involved in inhibiting inflammation and promoting cell secretion of antibacterial substances. Targeted therapies or immune checkpoint inhibitors that act on a single target mostly cause oral inflammation in patients to varying degrees. Therefore, balancing the immune system may be the future direction of research for oral ulcer drugs. Figures and Tables | References | Related Articles | Metrics

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Status and new development tendency of cosmetics whiteningefficacy evaluation Xue Wanting,Li Li,Dong Yinmao,Guo Miaomiao 2021, 51 (9):  890-896.  doi: 10.3969/j.issn.1001-1803.2021.09.012 Abstract ( 620 )   HTML ( 34 )   PDF (887KB) ( 589 )   With the rapid development of the cosmetics market and the deep affection from Oriental women for “whitening”, whitening cosmetics have become the focus of consumers and cosmetics companies. With the development of science and technology and the release of the “Regulations on Supervision and Administration of Cosmetics” in 2020, efficacy evaluation has become one of the key links in the research and development and marketing of cosmetics. Melanocytes produce melanin, which is transfered from the dendrites of melanocytes to keratinocytes, and finally follows the movement of epidermal cells to the stratum corneum to form color spots or to affect the skin color. Based on the mechanism of melanin synthesis and transportation, the evaluation methods of whitening efficacy were summarized and its development trend was put forward. The evaluation methods of whitening efficacy can be divided into physicochemical method, biochemical method, cell biology method and in vivo experiment. The principle and characteristics of 3D skin model, multiphoton imaging technology and other cutting-edge technologies are emphatically introduced, as well as some improvements in the original whitening efficacy evaluation model or method. In general, the evaluation methods of whitening efficacy will develop towards the combination of biotechnology, computer technology, high-tech instruments and skin physiology that are not easily affected by individual differences in the future, and will develop from single to multiple methods guided by mechanism. In addition, cosmetic producers should also improve their own technology and innovate more products. In the future, more and more excellent technologies and models are also needed to be applied to the whitening efficacy evaluation, so as to create a good development environment for the whole industry. Figures and Tables | References | Related Articles | Metrics

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Research progress on anti-hair loss mechanisms of plant extracts Wang Qiang,Shang Jiawei,Lu You,Lu Rongzhu 2021, 51 (9):  897-902.  doi: 10.3969/j.issn.1001-1803.2021.09.013 Abstract ( 629 )   HTML ( 40 )   PDF (1079KB) ( 573 )   Hair loss is a common disease, which is becoming more and more serious. It may cause emotional and psychological distress to patients, although it is not life-threatening. To date, the number of patients suffering from hair loss or alopecia has increased dramatically. Although two hair loss drugs, finasteride and minoxidil, have been approved by the Food and Drug Administration, their efficacy is limited and transient, due to low efficacy and undesirable side effects, such as pruritis, dryness, scaling, local irritation and dermatitis. Therefore, development of new products for alopecia treatment is one of the most attractive opportunities for the cosmetic industry. Many patients have attempted to find therapeutic herbs or compounds that function as safer and more potent treatments for alopecia. Hair follicle is the skin accessory organ that controls hair growth, and it is very sensitive to drugs, hormones and other factors. The hair growth cycle consists of three phases: anagen （growth phase）, catagen （regression phase）, and telogen （resting phase）. Dysregulation of the hair growth cycle has been shown to be associated with the pathogenesis of alopecia. Herbs or plant extracts can help prolong the anagen phase of hair follicle, prevent the progression from the anagen phase to the catagen phase, or promote the change from the telogen phrase to the anagen phase. Several traditional herbal medicines have been widely used for treating alopecia or preventing hair loss, with minimal or no side effects or toxicities. Hair growth was genetically regulated by many proteins and factors, such as insulin-like growth factor-1 （IGF-1）, β-catenin, keratinocyte growth factor （KGF）, hepatocyte growth factor （HGF）, sonic hedgehog （Shh）, transformation growth factor-β （TGF-β）, vascular endothelial growth factor （VEGF）, and 5α-reductase. This review elucidated the mechanisms of herbs or plant extracts that are relevant to hair loss, in order to provide theoretical basis for preventing and treating hair loss. Figures and Tables | References | Related Articles | Metrics

Analytical methods and testing

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Determination of 10 fluorescent colorants in cosmetics by high performance liquid chromatography with fluorescence detection Yuan Jianhui,Jiang Qingqing,Long Pei,Ma Ming,Zhou Hongbin,Xiao Daoqing 2021, 51 (9):  903-909.  doi: 10.3969/j.issn.1001-1803.2021.09.014 Abstract ( 365 )   HTML ( 14 )   PDF (1597KB) ( 315 )   A method for the simultaneous determination of 10 fluorescent colorants （fluorescein, sodium fluorescein, dibromofluorescein, diiodofluorescein, disodium diiodofluorescein, tetrabromofluorescein, disodium tetrabromofluorescein, tetrachloro-tetrabromofluorescein, disodium tetrachloro-tetrabromofluorescein and rhodamine B） in cosmetics by high performance liquid chromatography with fluorescence detection was established. This method was used to monitor the risk for more than 30 products including eyebrow pencils, lipsticks, eye shadows and blushers. The effects of extraction solvents on the fluorescent colorants were explored, and it is found that when the extraction solvent is methanol, the recovery rate of various fluorescent colorants can reach the best level. Meanwhile, to obtain higher sensitivity, the alkaline mobile phase glycine-methanol system was used to separate the fluorescent colorants. The effects of pH and concentration of glycine buffer solutions on the resolution and fluorescence intensity of the ten fluorescent colorants were also studied. It is found that when the pH is 9.0 and the concentration is 10 mmol/L, the resolution and fluorescence intensity of the 10 fluorescent colorants can achieve the best results. Finally, the fluorescent colorants were separated by Waters XBridge C18 （5 μm×4.6 mm×250 mm）column using 10 mmol/L glycine-methanol as the mobile phase, and qualitative and quantitative analysis was performed by high performance liquid chromatography with a fluorescence detector. The results show that there is a good linear relationship between concentration and peak area with R2 no less than 0.998. The limits of detection for diiodofluorescein and disodium diiodofluorescein are 1 μg/g and the limits of quantification are 3 μg/g, while the limits of detection for other fluorescent colorants are 0.2 μg/g and the limits of quantification are 0.5 μg/g. The average recoveries are from 88.7% to 118.5%, with relative standard deviations are in the range of 1.8%-8.2% （n=6）. This method has advantages such as simple pretreatment, high sensitivity and almost little interference from matrix. It is suitable for the simultaneous determination of the 10 fluorescent colorants in cosmetics. The method is expected to fill the gap in current detection methods and provide strong technical support for the quality monitoring and residue analysis of fluorescent colorants in cosmetics. Figures and Tables | References | Related Articles | Metrics

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Determination of 22 prohibited substances in hair growth cosmetics by HPLC-MS/MS method Gong Xu,Fang Fang 2021, 51 (9):  910-917.  doi: 10.3969/j.issn.1001-1803.2021.09.015 Abstract ( 209 )   HTML ( 15 )   PDF (1230KB) ( 232 )   A method of high performance liquid chromatography-tandem mass spectrometry （HPLC-MS/MS）was developed for simultaneous determination of 22 prohibited substances in hair growth cosmetics. After dispersed in saturated sodium chloride solution, the samples were ultrasonically extracted with acetonitrile, and separated by gradient elution. The analysis was performed under multiple reaction monitoring （MRM）. Matrix-matched standard curve was used for quantitative analysis. The results show that the 22 prohibited substances show good linear relationship within the range of corresponding mass concentrations with the correlation coefficients （r） more than 0.995. The limits of detection （LODs） are 4.9-49.7 ng/g. The average recoveries are within the range of 80.7%-110.3% with the RSD （n=6） less than 15% in the two matrices. With the advantages of simplicity, sensitivity and accuracy, the established method is suitable for the analysis of the 22 prohibited substances in hair growth cosmetics. Figures and Tables | References | Related Articles | Metrics

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Determination of 10 sex hormones in cosmetics by QuEChERS-UPLC Hu Bei,Li Lixia,Liu Hong,Huang Wei,Ding Xiaoping 2021, 51 (9):  918-924.  doi: 10.3969/j.issn.1001-1803.2021.09.016 Abstract ( 314 )   HTML ( 18 )   PDF (1341KB) ( 198 )   A method of QuEChERS coupled with ultra-high performance liquid chromatography was developed for determination of 10 sex hormones in cosmetics. The sample was dispersed using saturated sodium chloride, and purified by QuEChERS after acetonitrile ultrasound extraction. Chromatographic separation was achieved on a CORTECS C18+ column （2.1 mm×100 mm, 2.7 μm） by gradient elution using acetonitrile-water as mobile phase. PDA detector was used to test samples at multiple wavelengths, and external standard method was used for quantification. Results show that there is a good linear relationship for each of the 10 sex hormones in respective mass concentration range with their correlation coefficients （r） all above 0.99. The limits of detection （LOD） and the limits of quantitation（LOQ） for the 10 sex hormones are in the range of 0.02-0.1 μg/mL and 0.05-0.3 μg/mL, respectively. Average recoveries at three levels of 5, 25 and 50 μg/g are in the range of 81.2%-103.5%, with relative standard deviations （RSD, n=6） of 0.5%-12.0%. With the advantages of simplicity and good reproducibility, this method is suitable for the analysis of sex hormones in cosmetics. Figures and Tables | References | Related Articles | Metrics