超高效液相色谱-串联质谱法同时检测口腔卫生用品中的硝基咪唑类药物

建立了采用超高效液相色谱-串联质谱同时检测口腔卫生用品(牙膏及漱口水)中甲硝唑、替硝唑、奥硝唑、二甲硝咪唑和洛硝唑的方法。试样以0.1%(体积分数)的甲酸水溶液/乙腈(95:5, v/v)稀释,经高速离心后过滤膜净化,采用Cloversil C18色谱柱(100 mm×2.1 mm, 3.5 μm)分离,以0.1%甲酸水溶液和乙腈为流动相梯度洗脱,质谱检测,外标法定量。5种硝基咪唑类化合物在1.0～60.0 μg/L质量浓度范围内线性关系良好,相关系数r均不小于0.9992;在10.0、20.0和100 mg/kg加标水平的平均回收率为91.5%～108%,相对标准偏差为1.14%～5.22%;方法的定量限(LOQ,以信噪比为10计)为2.0 mg/kg。该方法可靠、稳定,可满足口腔卫生用品中硝基咪唑类药物含量检测与确证的需要。

Determination of nitroimidazoles in oral hygiene by ultra-performance liquid chromatography-tandem mass spectrometry

A method for the simultaneous determination of metronidazole, tinidazole, ornidazole, ronidazole and dimetridazole in oral hygiene by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) has been developed. The sample was diluted with 0.1% formic acid/acetonitrile (95:5, v/v), then centrifuged and filtered with a membrane. The separation was carried out on a Cloversil C18 column (100 mm x 2.1 mm, 3.5 microm) with the gradient elution of 0.1% formic acid and acetonitrile as the mobile phases. The analytes were determined by UPLC-MS/MS and quantified by external standard method. The calibration curves showed good linearity in the range of 1.0-60.0 microg/L with r > or = 0.9992. The recoveries were 91.5%-108% at the three spiked levels of 10.0, 20.0 and 100 mg/kg, and the relative standard deviations were 1.14%-5.22%. This method is easy, sensitive and suitable for the determination of nitroimidazoles in oral hygiene.