液相色谱-串联质谱法同时测定化妆品中的25种喹诺酮类药物

Determination of 25 quinolones in cosmetics by liquid chromatography-tandem mass spectrometry

建立了直接提取结合液相色谱-电喷雾串联质谱同时测定化妆品中丹诺沙星、恩诺沙星、氟甲喹、恶喹酸、环丙沙星、沙拉沙星、萘啶酸、诺氟沙星、氧氟沙星等25种喹诺酮类药物的方法。样品经酸性乙腈提取和正己烷脱脂净化,采用Poroshell EC-C18色谱柱分离,含0.1%甲酸的乙腈-水溶液为流动相进行梯度洗脱,电喷雾串联质谱正离子模式扫描,多反应监测（MRM）模式检测,外标法定量。实验通过空白基质液配制标准溶液,以降低基质对离子化干扰造成的基质效应,25种喹诺酮类药物在1~200 mg/kg范围内线性关系良好,相关系数（r）在0.999以上。方法的检出限为1.0 mg/kg,在1、5、10 mg/kg 3个加标水平下,水、乳、霜型化妆品中加标回收率为87.4%~105%,相对标准偏差（RSD）为4.54%~19.7%（n=6）。结果表明,该方法简便、快速、准确,适用于化妆品中25种喹诺酮类药物的测定。

An analytical method was developed for the simultaneous determination of 25 quinolones,including danofloxacin mesylate,enrofloxacin,flumequine,oxloinic acid,ciprofloxacin,sarafloxacin,nalidixic acid,norfloxacin,and ofloxacin etc in cosmetics using direct extraction and liquid chromatographyelectrospray ionization tandem mass spectrometry（LC-ESI-MS / MS）. Cosmetic sample was extracted by acidified acetonitrile,defatted by n-hexane and separated on Poroshell EC-C18 column with gradient elution program using acetonitrile and water（both containing 0. 1% formic acid）as the mobile phases and analyzed by LC-ESI-MS / MS under the positive mode using multiple reaction monitoring（MRM）. The interference of matrix was reduced by the matrix-matched calibration standard curve. The method showed good linearities over the range of 1- 200 mg / kg for the 25 quinolones with good linear correlation coefficients（r≥0. 999）. The method detection limit of the 25 quinolones was 1. 0 mg / kg,and the recoveries of all analytes in lotion,milky and cream cosmetics matrices ranged from 87. 4% to 105% at the spiked levels of 1,5 and 10 mg / kg with the relative standard deviations（RSD）of 4. 54%-19. 7%（n =6）. The results indicated that this method is simple,fast and credible,and suitable for the simultaneous determination of the quinolones in the above three types of cosmetics.