Abstract:
The effectiveness of highly polar agents in cancer treatment is well recognized, but their physicochemical properties make their analytical determination a demanding task. Their analysis requires peculiar sample preparation and chromatographic separation, which heavily impacts the precision of such an analytical method. As a case study, we chose a polar cytotoxic bleomycin, which is a mixture of complexing congeners with relatively high molecular mass, a fact that creates an added challenge in regard to its detection via electrospray mass spectrometry. These issues combined lead to a deprived method performance, so the aim of this study is manifold, i.e., to optimize, validate, and establish quality performance measures for determination of bleomycin in pharmaceutical and biological specimens. Quantification of bleomycin is done at diametrically different concentration levels: at the concentrations relevant for analysis of pharmaceutical dosage forms it is based on a direct reversed-phase HPLC-UV detection, involving minimum sample pretreatment. On the contrary, analysis of bleomycin in biological specimens requires phospholipid removal and protein precipitation followed by HILIC chromatography with MS/MS detection of bleomycin A2 and B2 copper complexes being the predominant species. This study further attempts to solve the traceability issue in the absence of certified reference standards, determines measurement uncertainty, investigates BLM stability and method performance characteristics, and, last but not least, provides an explanatory example of how a method quality assurance procedure should be established in case of an exceedingly complex analytical method.
摘要:
高度极性药物在癌症治疗中的有效性得到了广泛认可,但是它们的物理化学特性使它们的分析测定成为一项艰巨的任务。他们的分析需要特殊的样品制备和色谱分离,这严重影响了这种分析方法的精度。作为一个案例研究,我们选择了极性细胞毒性博来霉素,它是分子质量相对较高的络合同源物的混合物,这一事实在通过电喷雾质谱检测方面产生了额外的挑战。这些问题加在一起导致了一种被剥夺的方法性能,所以这项研究的目的是多方面的,即,为了优化,验证,建立药物和生物样品中博莱霉素的质量性能测定方法。博来霉素的定量是在完全不同的浓度水平下进行的:在与药物剂型分析相关的浓度下,它基于直接反相HPLC-UV检测,涉及最小的样品预处理。相反,分析生物标本中的博来霉素需要去除磷脂和蛋白质沉淀,然后进行HILIC色谱,MS/MS检测博来霉素A2和B2铜络合物是主要物种。本研究进一步试图在缺乏认证参考标准的情况下解决可追溯性问题,确定测量不确定度,研究BLM稳定性和方法性能特征,and,最后但并非最不重要的,提供了一个解释性的例子,说明在使用极其复杂的分析方法的情况下,应如何建立方法质量保证程序。