气相色谱-电子捕获法测定人血浆中单硝酸异山梨酯及制剂相对生物利用度研究

Determination of Isosorbide Mononitrate in Human Plasma by Gas Chromatography with Electron Capture Detector and Study on the Bioequivalence of Isosorbide Mononitrate Tablets

目的:建立测定人血浆中单硝酸异山梨酯的气相色谱-电子捕获法,研究两种单硝酸异山梨酯片的生物等效性。方法:以硝酸甘油为内标,血浆样品经乙酸乙酯提取后经Dikma-17石英毛细管柱分离后以气相色谱-电子捕获法测定。18名健康志愿者采用随机交叉方式分别单剂量口服单硝酸异山梨酯试验制剂和参比制剂40mg后研究二者的相对生物利用度。结果:血浆中单硝酸异山梨酯与内源性杂质分离完全,在2.9～731.5μg/L浓度范围内峰面积比与浓度线性关系良好,回归方程为:Y=0.006174X+0.2403(r2=0.998),最低定量限为2.9μg/L;单硝酸异山梨酯绝对回收率为85.5%～112.9%(n=20),内标绝对回收率为85.5%～92.1%(n=20),方法回收率为90.1%～107.8%(n=15),日内精密度(RSD)小于11.4%(n=15),日间精密度(RSD)小于11.7%(n=15)。单次服用40mg单硝酸异山梨酯片试验制剂(T)或参比制剂(R)后的AUC0→24分别为(3642.5±731.4)和(3658.8±832.8)μg.h.L-1;Cmax分别为(477.5±65.0)和(474.2±77.6)μg/L;Tmax分别为(1.3±0.4)和(1.1±0.3)h。与R相比,T的相对生物利用度为(100.8±12.1)%。结论:该法简单,准确度高,灵敏度好。方差分析表明两制剂的主要药动学参数之间差异无统计学意义,二者为生物等效制剂。

Objective：A gas chromatography with electron capture detector （GC-ECD） method was developed and validated to determine isosorbide mononitrate in plasma and evaluate the bioequivalenee of two isosorbide mononitrate tablets （T and R）. Methods： Isosorbide mononitrate was separated on a Dikma-17 column and was determined by GC-ECD method, and the internal standard was Nitroglycerin. A single oral dose of 40 mg isosorbide mononitrate was administered to 18 healthy volunteers in a randomized crossover study, and the pharmaeokinetics and bioavailability were studied. Results： Isosorbide mononitrate was separated well with the endogenous substances, the calibration curve was linear in the range of 2.9 - 731.5 μg/L with r^2 = 0. 998, the absolute recovery was in the rang of 95.5% - 112.9%（ n = 20）, and the method recovery was in the rang of 90.1% - 107.8% （ n = 15 ）, inter-day RSD 〈 11.4% （ n = 15 ） and intra-day RSD 〈 11.7% （ n = 15 ）. The AUC0→24 of the two tablets were （ 3642.5 ± 731.4） and （3658.8 ±832.8） μg · h · L^-1, Cmax were （477.5 ± 65.0） and （474.2 ±77.6） μg,/L, Tmax were （1.3±0.4） and （1.1±0.3） h. The relative bioavailability of tablets T was （100.8% ± 12.1% ） when compared with tablets R. Conclusions： The established method is aeeurate and sensible for determination of isosorbide mononitrate in human plasma. Statistic analysis showed no significant differenee between the two tablets, and bioequivalenee was observed.