高效液相色谱-串联质谱法测定健康女性使用塞克硝唑栓后体内塞克硝唑的浓度及其药动学研究

目的：建立快速灵敏高效液相色谱-串联质谱（HPLC-MS/MS）法测定健康女性使用塞克硝唑栓后体内塞克硝唑栓的浓度，并研究其在体内的药代动力学特征。方法：色谱柱Welch Ultimate C₁₈（2.1 mm×50 mm，5 μm）；流动相：乙腈-0.1%乙酸+5 mmol·L^-1乙酸铵水溶液（12：88，V/V）；流速：0.5 mL·min^-1，进样量5 μL。采用ESI+源，多重反应监测（MRM）模式，对离子反应m/z 186.3→128.3（塞克硝唑）和m/z 192.4→128.3（Secnidazole-d₆）进行监测。20名健康女性受试者，单次与多次给药试验各10名，分别给予塞克硝唑栓。根据检测的血浆中塞克硝唑浓度，用DAS 3.2.7进行数据处理以及SPSS 19.0对结果进行统计分析。结果：塞克硝唑在0.05~8.0 mg·L^-1范围内线性良好（r>0.99），定量下限0.05 mg·L^-1，批间、批内RSD皆小于15%。健康女性血浆中塞克硝唑栓单剂量C_max （3.00±0.96）mg·L^-1，t_max（8.90±2.68）h，t_1/2（18.07±2.96）h，AUC_0-96（97.78±35.81）mg·L^-1·h^-1，AUC_0-∞（101.11±36.96）mg·L^-1·h^-1；多剂量C_max，ss（6.01±2.01）mg·L^-1，t_max（7.20±2.86）h，t_1/2（21.87±7.60）h，AUC_ss（107.15±33.62）mg·L^-1·h^-1，AUC_0-96 （202.11±82.07）mg·L^-1·h^-1，AUC_0-∞（217.47±103.50）mg·L^-1·h^-1。结论：该方法灵敏、准确、可靠，专属性强，适用于塞克硝唑栓在人体内的药代动力学研究。

Determination of secnidazole by HPLC-MS/MS in healthy female individuals after using secnidazole suppositories and its pharmacokinetics study

OBJECTIVE To determine secnidazole and evaluate its pharmacokinetics in healthy female individuals by HPLC-MS/MS after using secnidazole suppositories. METHODS Chromatographic separation was performed by pumping the mobile phase into a Welch Ultimate C₁₈ (5 μm,2.1 mm×50 mm). Mobile phase was composed of acetonitrile and water (0.1% acetic acid and 5 mmol ammonium acetate) (12:88, V/V) at a flow rate of 0.5 mL·min^-1. Injection volume was 5 μL aliquot of solution. The precursor-fragments of secnidazole and secnidazole-d₆(internal standard) were m/z 186.3→128.3 and m/z 192.4→128.3 respectively, and were detected with the ESI source in positive ion and the multiple reaction monitoring (MRM) mode. Twenty healthy female volunteers, ten of whom were for single dose test and the remaining for repeated dose test, receiving secnidazole vagina suppositories. The concentration of secnidazole suppositories was determined by LC-MS/MS. Pharmacokinetic parameters and related statistics were calculated by DAS 3.2.7 and SPSS 19.0. The main pharmacokinetic parameters of single dose:C_max (3.00±0.96) mg·L^-1, t_max (8.90±2.68) h, t_1/2(18.07±2.96) h, AUC_0-96(97.78±35.81) mg·L^-1·h^-1, AUC_0-∞ (101.11±36.96) mg·L^-1·h^-1; repeated dose:C_max,ss(6.01±2.01) mg·L^-1,t_max(7.20±2.86) h,t_1/2(21.87±7.60) h,AUC_ss (107.15±33.62) mg·L^-1·h^-1,AUC_0-96 (202.11±82.07) mg·L^-1·h^-1,AUC_0-∞ (217.47±103.50) mg·L^-1·h^-1. RESULTS The range of calibration curve was 0.05 8 mg·L^-1 with a good correlation coefficient (r)>0.99. The lowest limit of quantification was 0.05 mg·L^-1. The intra and inter-batch precision values of the method were all less than 15%. CONCLUSION This method is fast, simple and sensitive, and is suitable for determination of accurate concentrations and pharmacokinetics of secnidazole suppositories in human plasma.