4'-(Aminomethyl)fluorescein hydrochloride

4'-(Aminomethyl)fluorescein is an excellent building block for developing fluoresceinated bioconjugates. Its amino group readily reacts with activated carboxy esters (such as NHS ester). The primary aliphatic amine of 4'-(aminomethyl)fluorescein can be reversibly coupled to aldehydes and ketones to form a Schiff base, which can be reduced to a stable amine derivative by sodium borohydride (NaBH4) or sodium cyanoborohydride (NaCNBH3) to form new probes. Carboxylic acids of proteins and other water-soluble biopolymers can be coupled to this molecule in aqueous solution using water-soluble carbodiimides such as EDAC. Spectral Data: lambdaex 494 nm, lambdaem 520 nm.