Matrix effect in quantitative LC/MS/MS analyses of biological fluids: A method for determination of finasteride in human plasma at picogram per milliliter concentrations
Matrix effect in quantitative LC/MS/MS analyses of biological fluids: A method for determination of finasteride in human plasma at picogram per milliliter concentrations
复制标题
DOI：
10.1021/ac971078
复制
发表时间：
1998-03-01
影响因子：
7.4
通讯作者：
Chavez-Eng, CM
中科院分区：
文献类型：
--
作者：
Matuszewski, BK;Constanzer, ML;Chavez-Eng, CM
与通常的看法相反，用高效液相色谱-串联质谱仪(LC/MS/MS)检测方法测定生物体液中药物的定量分析方法的可靠性和结果的药代动力学数据的完整性可能不是绝对的，由于样品基质引起的离子抑制、代谢物的干扰和“串扰”效应而导致的缺乏特异性和选择性，结果可能受到不利影响。通过分析I在流动相中直接进样的标准品，并将I和内标(II)的响应(峰面积)与峰进行比较，研究了离子抑制效应。在5个不同的血浆池中添加相同分析物的面积，并在提取后将标准添加到血浆提取物中，在色层条件下使用涡轮离子喷雾接口(TISP)进行LC/MS/MS分析，其特点是最小(总运行时间为2分钟，容量因子，I和II的k‘分别为1.50和1.75)和高保留率(总运行时间为6分钟，I和II的k’分别为3.25和13.25)，计算了不同血浆中I和II的绝对峰面积，并比较了标准曲线范围内所有浓度下的斜率和峰面积比，当在最小的高效液相保留条件下进行分析时，一组血浆样品的标准线斜率与其他来源的血浆样品的斜率有很大的不同(约高50%)，以变异系数(CV，%)表示的测定的精密度也不够高，在标准曲线范围内所有浓度下的斜率在15%~30%之间变化，当相同的实验采用高保留时，不同血浆来源的斜率几乎相同，变异系数提高到6%~14%。通过增加k‘和提供更多的分析物的色层保留，来自血浆基质的“看不见”的干扰大部分从分析物中分离出来，实际上消除了离子抑制，此外，通过更有选择性地从血浆萃取物中消除一些内源成分，离子抑制也被最小化，给出了详细的数据和这些实验的设计。此外，还描述了用加热的雾化器(HN)接口而不是TISP接口的LC/MS/MS建立了一种高灵敏度的分析方法，在这种情况下，没有观察到样品基质的影响。
Contrary to common perceptions, the reliability of quantitative assays for the determination of drugs in biological fluids using high-performance liquid chromatography with tandem mass spectrometric (LC/MS/MS) detection methods and the integrity of resulting pharmacokinetic data may not be absolute, Results may be adversely affected by lack of specificity and selectivity due to ion suppression caused by the sample matrix, interferences from metabolites, and "cross-talk" effects, Tn this paper, an example of the effect of the sample matrix on the determination of finasteride (I) in human plasma is presented, The ion suppression effect was studied by analyzing standards of I injected directly in mobile phase and comparing the response (peak areas) of I and an internal standard (II) with the peak. areas of the same analytes spiked before extraction into five different plasma pools and standards spiked into the plasma extracts after extraction, The LC/MS/MS analyses were performed using a turbo ion spray interface (TISP) under chromatographic conditions, characterized by minimal (total run time of 2 min, capacity factors, k' of 1.50 and 1.75 for I and II, respectively) and high retention of the analytes (total run time 6 min, k' of 3.25 and 13.25 for I and II, respectively), The absolute peak areas for I and II in different plasmas were calculated, and the slopes and peak area ratios at all concentrations within the standard curve ranges were compared, When analyses were performed under conditions of minimal HPLC retention, the slope of the standard line for one set of plasma samples was substantially different (about 50% higher) from that from other plasma sources, The precision of the assay, expressed as coefficient of variation (CV, %) was also inadequate and varied from 15 to 30% at all concentrations within the standard curve range, When the same experiments were repeated using high HPLC retention, the slopes from different plasma sources were practically the same, and the CV was improved to 6-14%. By increasing k' and providing more chromatographic retention of analytes, the "unseen" interferences from plasma matrix were mostly separated from analytes, practically eliminating the ion suppression, In addition, by eliminating from plasma extracts a number of endogenous components through more selective extraction, the ion suppression was also minimized, The detailed data and the design of these experiments are presented, In addition, development of a highly sensitive assay for I in human plasma at low picogram per milliliter concentrations using LC/MS/MS with a heated nebulizer (HN) interface, instead of a TISP interface, is described, In this case, the effects of sample matrixes were not observed.