HPLC法测定人血浆中奥硝唑浓度的不确定度评定

目的: 评定HPLC法测定人血浆中奥硝唑浓度的不确定度。 方法: 对奥硝唑浓度测定过程中各影响因素,包括测定精密度、称量、标准溶液的配制、含药血浆的配制、血浆提取、仪器、标准曲线拟合等进行分析评定,计算各变量的不确定度和合成不确定度,最终计算扩展不确定度。 结果: 人血浆中低(0.5 μg·mL^-1)、中(5 μg·mL^-1)浓度奥硝唑的扩展不确定度分别为0.088 μg·mL^-1、0.324 μg·mL^-1(P=95%,k=2)。 结论: HPLC法测定人血浆中奥硝唑浓度的不确定度主要由标准曲线拟合(尤其是低浓度)、标准溶液和血浆样品制备处理及仪器允差引入。

Objective: To evaluate uncertainty for the determination of ornidazole in human plasma by HPLC. Methods: It were analyzed that various factors affecting detection process,including repeatability,weighing,solution preparation,drug-spiked plasma preparation,solid phase extraction,HPLC error,calibration curve fitting,and so on.The expanded uncertainty was obtained by calculating each component of uncertainty and combined uncertainty. Results: The expand uncertainty of 0.5 μg·mL^-1 and 5 μg·mL^-1 was 0.088 μg·mL^-1,0.324 μg·mL^-1,respectively(P=95%,k=2). Conclusion: When determination of ornidazole in human plasma by HPLC,the uncertainty was mainly caused by the standard curve fitting(especially the low level of ornidazole),solution and plasma preparation,sample pretreatment and HPLC error.