加替沙星眼用凝胶的人血浆暴露水平分析

Human Plasma Exposure Level of Gatifloxacin Eye Gel

目的定量分析人血浆中加替沙星的浓度，研究加替沙星眼用凝胶连续7d给药后加替沙星在健康男性受试者体内的暴露特点。方法建立人血浆中加替沙星的LC—MS—MS定量分析方法，并对该方法的特异性、灵敏度、精密度与准确度、基质效应、回收率、稳定性等进行考察；测定10名男性健康受试者连续7d滴用加替沙星眼用凝胶后不同时间点血浆样品中加替沙星的浓度。结果LC-MS／MS定量分析人血浆中加替沙星的线性范围为2～500ng·mL-1；在5、10、50和400ng·mL-1浓度水平的准确度（RE）在±15．0％以内，批内精密度（RSD）在1．47％～2．61％之间，批间精密度（RSD）在1．79％-13．1％之间，基质效应、回收率、特异性、稳定性等进行考察均满足要求。受试者连续给药后所有血浆样品中加替沙星的药物浓度均低于定量下限（2ng·mL-1）。结论本实验建立了灵敏、准确的加替沙星定量分析方法，受试者连续7d滴用加替沙星眼用凝胶后在所有血浆样品中加替沙星的药物浓度均低于定量下限（2ng·mL-1）。

OBJECTIVE To determine gatifloxacin in human plasma, and study the exposure characteristics of gatifloxacin in Chinese healthy male volunteers who used Gatifloxacin Eye Gel for 7 d. METHODS LC-MS/MS method was developed for the quan- titation of gatifloxaein in human plasma. After protein precipitation with methanol and dilution with water, the chromatographic separa- tion was carried out on an Symmetry Cls column （4. 6 mm × 100 ram, 5μm） with a gradient mobile phase consisting of 0. 1% formic acid in methanol and 0. 1% formic acid in water at a flow rate of 0. 5 mL · min-1. The quantitation analysis was performed using multi- ple reaction monitoring （MRM） at the specific ion transitions of m/z 376. 2-→261.0 for gatifloxacin and m/z 332. 1±288. 1 for cipro- floxacin （internal standard） in the positive ion mode with eleetrospray ionization （ESI） source. Specificity, linearity, precision and accuracy, matrix effects, recovery and stability were investigated to validate the LC-MS/MS method. Plasma samples of different times from 10 Chinese healthy male volunteers were determined, who used Gatifloxacin Eye Gel for 7 d. RESULTS The linear range was 2 -500 ng · mL-1. The intra- and inter-day precisions were less than 2. 61% and 13.1%, and the accuracy was within ±5.0%. Ma- trix effective, recovery, specificity and stability were within ±15.0%. The concentration of gatifloxacin in human plasma was below the lower limit of quantitation （2 ng· mL- 1 ）. CONCLUSION This method is sensitive and accuracy for the determination of gatifloxa- cinin human plasma, and the plasma gatifloxacin level are all below the lower limit of quantitation （2 ng· mL- 1 ） in all subjects.