In this manuscript we describe our work on the development of a label-free chemoproteomics screening platform for cysteine reactive covalent fragments on a 96 well plate format. This platform profiles cysteine reactive fragments by competition with the hyper-reactive iodoacetamide desthiobiotin (IA-DTB) in cell lysates and live cells. We employ label free quantification and data independent acquisition (DIA) on an Evosep One – Bruker timsTOF Pro. In this submission we report this use of global proteomics to explore protein expression in HEK293T.