A novel organic solvent‐based coupling method for the preparation of covalently immobilized proteins on gold

A novel organic solvent‐based coupling method has been developed for the covalent immobilization of biological material to gold surfaces. The method employs the polar organic solvent anhydrous 2,2,2‐trifluoroethanol as the reaction medium and involves dissolution of the protein (catalase) in the solvent allowing protein coupling to proceed under basic conditions in a dry organic environment. The advantage of this method is that protein attachment is favored over hydrolysis of the coupling reagent. We have shown qualitatively and quantitatively that following attachment to the gold surface a significant proportion of the enzyme catalase remains catalytically active (at least 20–31%).