A fluorescent probe for specific detection of cysteine in the lipid dense region of cellsElectronic supplementary information (ESI) available: Invention disclosure no.: 2015-INV-0021. Details of synthesis, X-ray crystal data for ER-F, photophysical studies, and imaging studies. CCDC 1420800. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5cc07450a

A new cysteine (Cys) specific chemodosimetric reagent ( ER-F ) is used in imaging of endogenous Cys localized in the lipid dense region of the live Hct116 cells and the release of Cys within HepG2 cells from a drug following a biochemical transformation. A silica surface, modified with ER-F , could be used for quantitative estimation of Cys present in aqueous solution (pH 7.2) and in a human blood plasma (HBP). Use of a cysteine specific chemodosimetric receptor for probing its release in the ER-region of the HepG2 cells during drug metabolism and silica based strips for quantitative estimation of Cys in a human blood plasma sample.