Citation: WANG Qian, ZHENG Lin, REN Fei, WENG Dong-Hai, XU Jia-Ming, YANG Le-Ping, GAO Jia-Nan. Determination of Lead, Arsenic and Mercury in Cream Cosmetics by Total Reflection X-Ray Fluorescence Spectrometry Using Suspension Sampling. Chinese Journal of Analytical Chemistry, 2018, 46(4): 517-523. doi: 10.11895/j.issn.0253-3820.171353 [复制]
Determination of Lead, Arsenic and Mercury in Cream Cosmetics by Total Reflection X-Ray Fluorescence Spectrometry Using Suspension Sampling
建立了悬浮液进样-全反射X射线荧光光谱法（TXRF）快速测定清洁护理类膏霜化妆品中限用元素铅、砷和汞的方法。采用水-四氢呋喃-甲醇-Triton X-100混合溶剂均匀分散膏霜类化妆品。将分散后的测试液移入样品载体，干燥，利用共聚维酮减少汞在烘干过程中的损失和沉积物在石英载体上的扩散。研究了样品干燥造成的元素损失，以及Triton X-100和共聚维酮对减少元素干燥损失和分散沉积物的作用；讨论了基体效应、元素间的光谱干扰情况、内标元素及分析谱线的选择。采用基体加标的方法建立校准曲线，在一定范围内避免了软件解谱和厚样引起的误差。铅、砷、汞在0.01~1.60 μg/mL浓度范围内线性关系良好（R2≥0.998），检出限（S/N=3）分别为0.005、0.004和0.006 μg/mL，测定精密度（RSD，n=11）分别为7.8%-14.9%、6.6%-13.3%和7.6%-14.6%。采用本方法对膏霜类化妆品标准参考物质进行分析，并与标准方法（微波消解-电感耦合等离子体质谱法）的测定结果进行比较，本方法测定结果与标准物质和标准方法的结果一致。
A method for the determination of trace elements such as lead, arsenic and mercury in cream cosmetics by total reflection X-ray fluorescence spectrometry (TXRF) with suspension sampling was developed. The mixed solvents of water, tetrahydrofuran, methanol and were used to disperse paste, cream, and additives of triton X-100 to promote the test liquid uniform. The test suspension fluid were taken into the sample carrier, drying and then introduced into TXRF. Poly (1-vinylpyrrolidone-co-vinyl acetate) (P(VP-co-VAc)) was added to curing sediments, inhibiting proliferation. Triton X-100 and P(VP-co-VAc) were found to have the function of reducing mercury loss in the drying process. The loss of elements in the drying process and the effect of triton X-100 and P(VP-co-VAc) were investigated. The effect of cream matrix, element interference, spectral line and the inner standard were discussed. The calibration curves for quantitative analysis were established using matrix standards, so the error of software decomposition peak and the error caused by thick sample were avoided within a certain range. In this work, the linear correlation coefficients of Pb, As and Hg calibration curve were greater than 0.998 The detection limit of Pb, As and Hg in the solution were 0.005, 0.004 and 0.006 μg/mL, respectively. Relative standard diviations(RSDs, n=11) of Pb, As and Hg were 7.8%-14.9%, 6.6%-13.3% and 7.6%-14.6% respectively. The results of Pb, As, and Hg in cream cosmetics determinated by this method agreed with those obtained from inductively coupled plasma atomic emission spectrometry and the value of standard reference material. The TXRF method was proved to be accurate, simple and valuable in determination of trace heavy metal ions in cosmetic samples.
China food and Drug Administration . Safety and Technical Standards For Cosmetics. Beijing: 中国标准出版社, 2015
国家食品药品监督管理总局. 化妆品安全技术规范. 北京: 中国标准出版社, 2015
GB/T 18670-2002. Cosmetic Classification. National Standards of the People's Republic of China
化妆品分类. 中华人民共和国国家标准. GB/T 18670-2002