Most drugs exert pharmacological effects through interaction with their target proteins.Therefore, drug target identification is a crucial step towards the understanding of the mechanism of drug action.It is also imperative to study the pharmacodynamics of a known drug, with an aim to discover the potentially unrevealed actions and thus refine its future clinical applications.Currently, drug-target identification is either through in vitro affinity chromatography-based approaches or in vivo activity-based protein profiling (ABPP) approaches.