Immobilization of His-Tagged Proteins through Interaction with L-Cysteine Electrodeposited on Modified Gold Surfaces

Abstract

A method for preparing a high-density His-tagged protein array was developed. The method is based on specific binding between His-tags and Ni ions chelated with the carboxyl groups of L-cysteine applied to the substrate surface by electrodeposition. About 13 ng/mm2 of His-tagged green fluorescent protein (His-GFP) could be immobilized on the substrate. The immobilized His-GFP could be subsequently released by washing with imidazole, suggesting that immobilization involves specific binding between the His-tag and the Ni ion complex.