高效液相色谱法测定尿液中阿仑膦酸钠的浓度

 目的 建立阿仑膦酸钠在人体内尿药浓度的高效液相色谱-荧光检测法，并应用于药动学研究。方法 采用Shisheido Capcell Pak C₁₈(4.6 mm×150 mm，5 μm)色谱柱，洗脱方式：梯度洗脱，流动相A：25 mmol·L^-1柠檬酸-25 mmol· L^-1焦磷酸钠；流动相B：水；流动相C：乙腈-甲醇（1∶1），流速为1.0 mL· min^-1，柱温40 ℃；内标物：帕米膦酸钠；荧光检测：激发波长为260 nm；发射波长为310 nm。28名健康受试者服用阿仑膦酸钠片70 mg后，测定阿仑膦酸钠的尿药浓度，并计算药动学参数。结果 在25~5 000 μg·L^-1内，阿仑膦酸钠与内标峰面积的比值与浓度呈良好的线性关系（r=0.998 7）。日内及日间精密度（RSD）和准确度（RE）均符合要求。阿仑膦酸钠片在体内的累积排泄量A_et为（253 830±267 241）ng，最大排泄速率U_max为（58 508±55 394）ng·h^-1。结论 本试验提供了阿仑膦酸钠体内尿药浓度的HPLC测定方法及药动学参数，为临床应用提供了依据。

Determination of Alendronate Sodium in Human Urine by HPLC with Fluorescence Detector

OBJECTIVE To develop and validate a reliable analytical method for the pharmacokinetic study of alendronate sodium in human urine by a high performance liquid chromatography (HPLC) system with fluorescence detector.METHODS Liquid chromatography was performed on a Capcell Pak C₁₈ column (4.6 mm×150 mm, 5 μm particles),using a gradient method starting with mobile phase acetonitrile/methanol-citrate/pyrophosphate buffer (35∶65) at 1.0 mL· min^-1 and 40 ℃.The total run time was 25 min. The fluorometric detector was operated at 260 nm (excitation) and 310 nm (emission). Pamidronate sodium was used as the internal standard. RESULTS The linearity of calibrated curves of urine samples was in the range of 25-5 000 μg·L^-1 (r=0.998 7). The intra- and inter-day precision expressed as the relative standard deviation（RSD） was less than 15%. The limit of quantitation was 25 μg·L^-1of alendronate sodium in 5 mL urine. Following the oral administration of 70 mg alendronate sodium tablet to volunteers, the cumulative amount of alendronate sodium was excreted (A_et) and peak excretion rate (U_max) were (253 830±267 241 )ng and （58 508± 55 394.5） ng·h^-1 respectively. CONCLUSION The method was demonstrated to be highly feasible and reproducible and offered a satisfactory tool for the pharmacokinetics and relative bioavailability of alendronate sodium in urine samples.