Invitrogen™ Alexa Fluor™ 350 Hydrazide

Invitrogen™ Alexa Fluor™ 350 Hydrazide

The primary aliphatic amine of 5-(aminoacetamido)fluorescein (fluoresceinyl glycine amide) 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 (NaCNH3) 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 (E2247). The glycine may be the better amine probe for direct carbodiimide-mediated coupling, since it is likely to remain unprotonated at a lower pH than other aliphatic amines.