高效液相色谱-质谱法研究依托红霉素颗粒的生物等效性

Bioequivalence of erythromycin estolate granules determined by HPLC-MS

目的：建立人血浆中红霉素和红霉素丙酸酯的高效液相色谱-质谱测定法，并研究其在健康志愿者的药动学及相对生物利用度。方法：单剂口服依托红霉素颗粒450mg后，血样经二氯甲烷-正己烷（3：2）提取，进行LC．MS分析。结果：红霉素丙酸酯的线性范围为19．4—2910．0ng·mL^-1，定量下限为19．4ng·mL^-1，提取回收率为87．9％～94．3％；红霉素的线性范围为20．3～1014．0ng·mL^-1，定量下限为20．3ng·mL^-1，提取回收率为76．0％～84．8％。人体中红霉素丙酸酯的药动学参数为：Cmax为（3114．8±554．9）ng·mL^-1，Tmax为（2．20±0．47）h，t1／2为（2．86±0．69）h，AUC0-t为（14699±2605）ng·h·mL^-1，；红霉素的药动学参数为：Cmax为（910．3±213．5）ng·mL^-1，Tmax为（1．75±0．30）h，t1/2为（3．69±0．94）h，AUC0-t为（4173±1121）ng·h·mL^-1。结论：2种依托红霉素素制剂具有生物等效性，本方法灵敏、准确、简便，适用于临床药动学及生物等效性研究。

Objective： To develop an HPLC-MS assay for determining erythromycin propionate and erythromycin in human plasma, and to estimate the relative bioavailability and pharmacokinetics of erythromycin estolate in healthy volunteers. Methods ： After being extracted with dichloromethane - N-hexane （3： 2）, plasma was separated using a C18 column with a mobile phase of 0.1% formic acid-acetonitril （20： 80）, and analyzed by MS detector. A clinical trial was performed in 20 healthy volunteers. For each volunteer, a single dose of 450 mg erythromycin estolate granules was administrated. Results： The calibration curve of erythromycin propionate was linear over the range of 19.4 - 2 910.0 ng·mL^-1, the quantitative limit for erythromycin propionate in plasma was 19.4 n·mL^-1, and the recovery was 87.9% -94.3%. The calibration curve of erythromycin was linear over the range of 20.3 - 1 014.0 n·mL^-1, the quantitative limit for erythromycin in plasma was 20.3 n·mL^-1, and the recovery was 76.0% -84.8%. The main pharmacokinetic parameters of the test tablets and reference were as follows： the Cmax of erythromycin propionate was （ 3 114.8 ± 554.9 ） n·mL^-1, TX was （2.20 -＋ 0.47 ） h, tl/2 was （2.86 ± 0.69 ） h and AUC0-t was （14699±2605） ng·h·mL^-1; the Cmax of erythromycin was （910.3±213.5） n·mL^-1, Tmax was （1.75±0.30） h, t1/2 was （3.69±0.94） h and AUC0-t was （4173±1121） ng·h·mL^-1 Conclusion： The two formulations of erythromycin estolate are bioequivalent. The assay for determining erythromycin estolate is proved to be sensitive, accurate and convenient, and can be applied in clinical pharmacokinetic studies.