Matthew James | Authors


Low-Level Determination of Mutagenic Nitrosamine Impurities in Drug Substances by LC–MS/MS

This article discusses the development of a series of applications that will allow for the determination of a number of nitrosamines that have been identified by the FDA as genotoxins to monitor, initially showing how to perform a separation of these compounds from the API and then looking at how MS can be applied to the analysis to ensure that the required detection limits can be reached.

Maximization of Selectivity in Reversed-Phase Liquid Chromatographic Method Development Strategies

The selectivity of different combinations of organic modifiers, pH, and types of reversed-phase liquid chromatography (LC) materials has been characterized using Tanaka column characterization, linear solvent energy relationships (LSER), and selectivity correlations. The three characterization techniques highlighted the potential complementary selectivity of these phases and conditions as well as the type and dominancy of some of the retention mechanisms involved. Subsequently, selectivity differences were proven to be valid in the practical separation of acids, bases, and neutral analytes. This paper aims to assist chromatographers in producing highly efficiency method development strategies for reversed-phase LC separations in a relatively short time frame.