Lead Fractionation Analysis in Lipstick Samples by Inductively Coupled Plasma-Mass Spectrometry

A new analytical approach based on fractionation was introduced for lead in lipstick samples. Different separation techniques including n-hexane, glycerol extraction, and activated carbon adsorption were used to characterize the lipid fraction, polar and aromatic components of the samples. Additionally, artificial saliva and food stimulant extractions were used for the risk assessment studies. Trace metal levels in fractions were determined by inductively coupled plasma-mass spectrometry. Method validation parameters in the total element determinations were defined in terms of detection limits, accuracy, and precision. The limits of detection and quantification were 0.02 and 0.07 mg kg^?1 for Pb; whereas the repeatability and reproducibility of the results based on percent relative standard deviation were 3.0% and 7.2% for lead, respectively.     

Application of a thiourea‐containing task‐specific ionic liquid for the solid‐phase extraction cleanup of lead ions from red lipstick,pine leaves,and water samples

Here, task‐specific ionic liquid solid‐phase extraction is proposed for the first time. In this approach, a thiourea‐functionalized ionic liquid is immobilized on the solid sorbent, multiwalled carbon nanotubes. These modified nanotubes packed into a solid‐phase extraction column are used for the selective extraction and preconcentration of ultra‐trace amounts of lead(II) from aqueous samples prior to electrothermal atomic absorption spectroscopy determination. The thiourea functional groups act as chelating agents for lead ions retaining them and so, give the selectivity to the sorbent. Elution of the retained ions can be performed using an acidic thiourea solution. The effects of experimental parameters including pH of the aqueous solution, type and amount of eluent, and the flow rates of sample and eluent solutions on the separation efficiency are investigated. The linear dependence of absorbance of lead on its concentration in the initial solution is in the range of 0.5–40.0 ng/mL with the detection limit of 0.13 ng/mL (3s_b/m, n = 10). The proposed method is applicable to the analysis of red lipstick, pine leaves, and water samples for their lead contents.     

快速提取-超高效液相色谱法测定唇膏中11种酞酸酯

建立快速提取–超高效液相色谱法测定唇膏中11种酞酸酯的检测方法。将唇膏样品涂覆在定量滤纸上,用甲醇涡旋超声提取,色谱柱采用Waters ACQUITY UPLC BEH C_(18)柱(100 mm×2.1 mm,1.7μm),流动相为乙腈–水,梯度洗脱,流量为0.5 mL/min,用PDA检测器检测,检测波长225 nm。以3倍空白噪音计,邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)的检出限分别为1,2 mg/kg;邻苯二甲酸二丙酯(DPRP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二戊酯(DPP)、邻苯二甲酸二己酯(DHXP)、邻苯二甲酸丁基苄基酯(BBP)、邻苯二甲酸二(2–乙基)己酯(DEHP)、邻苯二甲酸二正辛酯(DNOP)的检出限为3 mg/kg;邻苯二甲酸二异壬酯(DINP)、邻苯二甲酸二异癸酯(DIDP)的检出限为30 mg/kg。方法的加标回收率为86.6%~98.6%,测定结果的相对标准偏差为0.6%~6.0%(n=6)。该方法样品处理简单,提取效率高,分离效果好且灵敏度高,结合色谱图和紫外光谱图,能快速准确测定唇膏中11种酞酸酯。     

Ultrasonic Extraction Coupled with Capillary Electrophoresis for the Determination of Azo Dyes in Lipsticks Using Ionic Liquid as Dynamic Coating and Background Electrolyte

A simple and rapid method based on ultrasonic extraction and capillary electrophoresis using 1‐butyl‐3‐methylimidazolium tetrafluoroborate as dynamic coating and background electrolyte was developed. The method was applied to the separation and determination of three azo dyes in two lipsticks. To increase extraction rate and yield, lipstick samples were coated on a glass slide before ultrasonic extraction. The dyes were extracted by ultrasonic extraction for 30 min, and then determined by capillary electrophoresis. Several experimental factors, such as ionic liquid concentration, pH value of background electrolyte and applied voltage, were examined and optimized. Under the optimal conditions, three azo dyes were completely separated within 12 min, and the detection limits for the three azo dyes ranged from 0.33 to 0.88 μg/mL. The recoveries were in the range of 96.8% to 108.8%.     

LIBS技术对羊毛脂复合物中重金属元素的成分分析

利用激光诱导击穿光谱技术对市面上某型号口红的羊毛脂复合物中重金属元素进行分析,使用波长为532nm的激光在口红表面击穿诱导高温等离子体,通过对MCP增益、延迟、门宽三个参数的优化来获得最佳光谱.由发射光谱线的强度计算等离子体的电子温度,研究了激光诱导等离子体的电子温度随时间演化的特性.