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1.
随着科技进步和产业提升,人们不断从本源上追求美、从长效上保持美、从机制上激发美。众多肽类化合物,已被证实在人体内具有独特的生物学促进或抑制作用,也因此被广泛应用于美妆产品。以化妆品中生物活性肽的不同功效为主线,对其化学结构进行分析并阐述其中的生理作用机制。  相似文献   
2.
建立气相色谱-质谱法快速测定化妆品中甲基柏木酮、甲基柏木醚、壬酸3种香精香料的方法。样品用甲醇超声提取,经高速冷冻离心,上清液干燥脱水后经0.45 μm滤膜过滤,直接注入气相色谱-质谱仪进行测定,用选择离子和保留时间定性,外标法定量。甲基柏木酮、甲基柏木醚、壬酸在各自的质量浓度范围内与色谱峰面积成良好的线性关系,相关系数分别为0.9992,0.9991,0.9994,检出限分别为0.05,0.1,0.1 mg/kg。测定结果的相对标准偏差为2.1%~6.6%(n=5),样品加标回收率为91.5%~97.7%。该方法准确度和灵敏度高,样品用量少,前处理简单,可同时测定化妆品中3种香精香料。  相似文献   
3.
We utilized ultra‐high performance liquid chromatography with tandem mass spectrometry and dispersive solid‐phase extraction to develop a new method for the detection of nine analytes (scopolamine, cephaeline, strychnine, hyoscyamine, brucine, hydrastine, ajmalicine, colchicine, and oleandrin) in herbal cosmetics. Acetonitrile/water and 2‐propylaminoethylamine were used to disperse and purify during the dispersive solid‐phase extraction step. The analytes were separated by a Waters UPLC HSS T3 column and detected through electrospray ionization source in the positive mode with multi‐reaction monitoring conditions. Under the optimal conditions, the calibration curves were linear in the range of 0.2–100.0 μg/L with the correlation coefficients higher than 0.995. The method limit of quantitation (S/N = 10) were 5.0 μg/kg for oleandrin and 1.0 μg/kg for the other eight alkaloids. The mean recoveries at three spiked concentration levels of 1.0–10.0 μg/kg were in the range of 86.9–116.5% with the intra‐day relative standard deviations (n  = 6) ranging from 2.4 to 8.8%, and inter‐day relative standard deviations ranging from 2.7 to 5.7%. This method is accurate, simple and rapid, and has been applied to the quality supervision of herbal cosmetics in Guangzhou.  相似文献   
4.
5.
A carboxylated graphene oxide/polyvinyl chloride (CGO/PVC) material was prepared as a sorbent for the selective extraction of sulphonamides from complex sample. After being dispersed in buffer solution, sample was transferred into the prefabricated solid-phase extraction (SPE) column, which integrated extraction and cleanup into one single-step. A multi-response optimization based on the Box-Behnken design was used to optimize factors affecting extraction efficiency. Compared with the commonly commercial sorbents including MCX, WCX and C18, CGO/PVC hybrid material had higher extraction selectivity and capacity to sulphonamides. The limits of detection and quantification for seven target compounds were in the range of 3.4–7.1 μg/L and 11.4–23.7 μg/L, respectively. The self-assembly SPE cartridge was successfully used to enrich seven analytes in anti-acne cosmetics prior to ion chromatography detection with good recoveries of 87.8–102.0% and relative standard deviations of 1.2–6.4%, implying that this method was suitable for routine analysis of cosmetics.  相似文献   
6.
Development of new formulations for topical use and cosmetic and pharmaceutical delivery agents has increased the complexity of emulsified systems. Liquid crystals, known since the nineteenth century are the third phase of an emulsion, being responsible for increasing its stability and the solubility of substances poorly soluble in water, or the oily phase, modulating the release of drugs imprisoned in its structure and promoting hydration of the skin surface. In the present work we developed oil/water emulsions, making use of Marigold oil (Calendula officinalis L) and ethoxylated fat alcohols as surfactant. The required HLB value for marigold oil was determined to be 6.0. The surfactants were associated in lipophilic/hydrophilic pairs. The lipophilic surfactants were Ceteth‐2 and Steareth‐2 and the hydrophilic surfactants were Steareth‐20, Ceteareth‐20, Ceteareth‐5, and Ceteth‐10. To identify the liquid crystalline phases, the emulsions were analyzed by polarized light microscopy. The physical stability was evaluated by rheology and zeta potential analysis. All emulsions presented lamellar liquid crystal structures. Results showed that this type of surfactant is able to produce liquid crystal in the system, with slight difference in appearance, influencing the physical stability, according to the methods applied.  相似文献   
7.
高效液相色谱法测定化妆品中10种限用物质   总被引:1,自引:0,他引:1  
建立了乙腈超声提取、高效液相色谱/二极管阵列检测快速测定化妆品中的氢醌、水杨酸、苯酚、苯氧乙醇、对羟基苯甲酸甲酯、对羟基苯甲酸乙酯、对羟基苯甲酸丙酯、对羟基苯甲酸丁酯、双氯酚、三氯生10种限用物质含量的分析方法.对提取方法、液相色谱条件和检测条件进行了优化,10种限用物质标准溶液的线性范围为0.01~0.1g/L,50...  相似文献   
8.
A fast methodology for the assay of parabens in drug and cosmetic preparations has been presented. The procedure developed is based on paper spray tandem mass spectrometry and isotope dilution approach. For each investigated paraben, the corresponding labeled standard has been used in order to improve the accuracy and reproducibility of the analyses. The MS experiments have been performed under MRM conditions, monitoring the transitions [M‐H]? → m/z 92 and [M‐H]? → m/z 98, respectively, for each analyte and the corresponding labeled internal standard. The quantitative assay has been performed using a calibration curve built from 2 to 15 mg/L. The method accuracy, in all case near 100%, was evaluated using fortified samples at two concentration levels, which are representative of the lower and the higher portion of calibration curve. The good values of LOQ, LOD, and reproducibility confirm the consistency of the developed approach.  相似文献   
9.
建立了化妆品中西咪替丁及雷尼替丁的高效液相色谱-四极杆/飞行时间高分辨质谱检测方法,并对其质谱裂解规律进行研究。待测样品经甲醇超声提取,过滤膜后经Zorbax SB-Aq色谱柱(3.0 mm×100 mm,1.8μm)分离,用乙腈-含0.1%甲酸的水溶液梯度洗脱后,在双喷雾电喷雾离子源正离子模式下检测,数据采集使用一级母离子全扫描和目标二级离子扫描。在不同的化妆品基质中,西咪替丁和雷尼替丁分别在5.65~113 ng/mL和4.95~99.0 ng/mL范围内线性关系良好(r0.999),检出限分别为1.1、0.99 ng/mL,定量下限分别为5.6、5.0 ng/mL;2种待测物在低、中、高3个加标水平下的回收率为86.7%~110%,相对标准偏差(RSD)为0.90%~6.0%,方法重复性良好(RSD10%)。该方法前处理简单,灵敏度较好,线性、回收率及重复性均满足方法学要求,可用于化妆品中西咪替丁和雷尼替丁的筛查测定。  相似文献   
10.
A simple, fast, and sensitive analytical protocol using fabric‐phase sorptive extraction followed by high performance liquid chromatography with ultraviolet detection has been developed and validated for the extraction of five parabens including methylparaben, ethylparaben, propylparaben, butylparaben, and benzylparaben. In the present work, sol‐gel polyethylene glycol coated fabric‐phase sorptive extraction membrane is used for the preconcentration of parabens (polar) from complex matrices. The use of fabric‐phase sorptive extraction membrane provides a high surface area which offers high sorbent loading, shortened equilibrium time, and overall decrease in the sample preparation time. Various factors affecting the performance of fabric‐phase sorptive extraction, including extraction time, eluting solvent, elution time, and pH of the sample matrix, were optimized. Separation was performed using a mobile phase consisting of water:acetonitrile (63:37; v/v) at an isocratic elution mode at a flow rate of 0.9 mL/min with wavelength at 254 nm. The calibration curves of the target analytes were prepared with good correlation coefficient values (r2 > 0.9955). The limit of detection values range from 0.252 to 0.580 ng/mL. Finally, the method was successfully applied to various cosmetics and personal care product samples such as rose water, deodorant, hair serum, and cream with extraction recoveries ranged between 88 and 122% with relative standard deviation <5%.  相似文献   
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