Simultaneous determination of 27 preservatives in toothpaste by high-performance liquid chromatography

A method of high-performance liquid chromatography(HPLC)was established for simultaneous determination of 27 preservatives in toothpaste.Toothpaste samples were extracted with 50%aqueous methanol solution,ultrasonicated and then filtered.The target compounds were separated on a C_(18) column(250 mm×4.6μm,5μm)with the mobile phase consisting of acetonitrile and aqueous phosphoric acid solution,the column temperature was 30℃,the sample volume was 10μL,the flow rate was 1 mL/min,and diode array detector was used.Under the optimal experimental conditions,good linear relationship was obtained and the correlation coefficient(R^(2))was greater than 0.9995.This method was accurate and sensitive,which was suitable for the qualitative and quantitative analysis of 27 preservatives in toothpaste.

超级微波消解-ICP-MS法测定洗发类化妆品中37种元素

采用超级微波消解-电感耦合等离子体质谱(ICP-MS)建立了洗发类化妆品中37种元素含量的测定分析方法。样品经超级微波消解仪消解后,采用铼(Re)、铑(Rh)作为内标元素,采用ICP-MS同时测定洗发类化妆品中铅(Pb)、砷(As)、汞(Hg)、镉(Cd)、锂(Li)、铍(Be)、钪(Sc)、钒(V)、钴(Co)、镍(Ni)、铬(Cr)、锰(Mn)、铜(Cu)、铷(Rb)、锶(Sr)、镨(Pr)、钕(Nd)、镝(Dy)、银(Ag)、铟(In)、铯(Cs)、钡(Ba)、铊(Tl)、铋(Bi)、钍(Th)、镧(La)、铈(Ce)、铒(Er)、铕(Eu)、钆(Gd)、钬(Ho)、镥(Lu)、钐(Sm)、铽(Tb)、铥(Tm)、钇(Y)、镱(Yb)37种元素的含量。该方法在一定浓度范围内线性关系良好,线性相关系数均≥0.9950,低、中、高浓度加标回收率范围为87.1%~113.5%,RSD为0.72%~5.00%(n=6)。该方法专属性强、灵敏度高、可快速、准确测定洗发用品中37种金属元素。