高效液相色谱法同时测定防晒类化妆品中15种紫外线吸收剂

建立了一种反相高效液相色谱同时测定防晒类化妆品中15种紫外线吸收剂的分析方法。化妆水、乳液、膏霜和蜡质样品中首先加入四氢呋喃(含2 g/L氢氧化铵),涡旋、振荡、混匀(若蜡质样品仍分散不完全,可超声振荡加热至50 ℃),再加入80%(v/v)甲醇水溶液振荡混匀、超声提取、离心、过滤后,采用XTerra MS C₁₈柱分离,经水(含0.1%(v/v)甲酸)和甲醇(含0.1%(v/v)甲酸)梯度洗脱,以二极管阵列检测器检测,检测波长为280 nm和311 nm,外标法定量。实验中对不同基质类型样品的前处理条件(样品分散溶剂、萃取溶剂和萃取时间等)进行了重点优化。结果表明,15种紫外线吸收剂在各自的线性范围内呈良好的线性关系(r²≥0.9991),方法的定量限为1.2~5.1 μg/g,在低、中、高3个添加水平下的回收率为84.2%~100.7%,相对标准偏差(RSD)为0.9%~9.5%。该分析方法分离效果好、灵敏度高、定量准确,可用于防晒类化妆品的实际检测。

Simultaneous determination of fifteen ultraviolet filters in sunscreen cosmetics by high performance liquid chromatography

An analytical method for the simultaneous determination of fifteen ultraviolet (UV) filters in sunscreen cosmetics was developed by high performance liquid chromatography (HPLC). Various cosmetic samples including lotions, emulsions, creams and waxes were firstly mixed thoroughly by adding tetrahydrofuran containing 2 g/L ammonium hydroxide followed by vortex and oscillation. If the wax samples were still homogenized incompletely, a ultrasonic oscillation protocol with heating to 50 ℃ was adopted. The homogeneous samples were then ultrasonically extracted by 80% aqueous methanol solution. After centrifugation and micropore filtration, the extracted components were separated on an XTerra MS C₁₈ column with gradient elution by water containing 0.1%(v/v) formic acid and methanol containing 0.1%(v/v) formic acid, determined by a diode array detector (DAD) at 280 nm and 311 nm, and quantified using external standard method. Optimization for the pretreatment conditions of different matrices of cosmetics including sample dispersion solvents, extraction solvents and time were carried out. This developed method showed good linearity (r²≥0.9991) and the limits of quantification (LOQs) were between 1.2 and 5.1 μg/g. The recoveries of the fifteen compounds ranged from 84.2% to 100.7% at three spiked levels with the relative standard deviations (RSDs) between 0.9% and 9.5%. The analytes were well separated and this analytical method proved to be sensitive and accurate, so it can be used in the practical determination of the fifteen UV filters in commercial sunscreen cosmetics.