Defining drug purity through chromatographic and related methods: current status and perspectives

Chromatographic and electrophoretic techniques play a preeminent role in assessing the quality of drug substances and drug products. Current ICH guidelines place in a legal framework what has been common practice in modern pharmaceutical research and quality control. This paper reviews some aspects of current requirements for evaluating the purity of chemically synthesized new drug substances and drug products, and suggests some possible future trends.