Biomolecule Immobilization 127 Applied Biochemistry and Biotechnology Vol. 89, 2000 Copyright © 2000 by Humana Press Inc. All rights of any nature whatsoever reserved. 0273-2289/00/89/0127/$13.00 127 *Author to whom all correspondence and reprint requests should be addressed. Biosensors Based on Immobilization of Biomolecules by Electrogenerated Polymer Films New Perspectives SERGE COSNIER Laboratoire d’Electrochimie Organique et de Photochimie Rédox, UMR CNRS 5630, Université Joseph Fourier Grenoble 1, BP 53, 38041 Grenoble, Cedex 9, France, E-mail Serge.Cosnier@ujf-grenoble.fr Abstract The concept and potentialities of electrochemical procedures of bio- molecule immobilization are described. The entrapment of biomolecules within electropolymerized films consists of the application of an appropriate potential to an electrode soaked in an aqueous solution containing monomer and biomolecules. This method of biosensor construction is compared with a two-step procedure based on the adsorption of an aqueous amphiphilic pyrrole monomer-biomolecule mixture on an electrode followed by the electropolymerization of the adsorbed monomers. Another approach is based on the electrogeneration of polymer films functionalized by specific groups allowing subsequently the attachment of biomolecules. The immobi- lization of biomolecules on these films by covalent binding or noncovalent interactions is described. Index Entries: Avidin; biosensor; biotin; enzyme; functionalized polymer; polypyrrole. Introduction The ingenious concept of combining the recognition properties of macromolecular biological molecules to the sensitivity of electrochemical devices has led to the emergence of biosensors as valuable analytical tools for the monitoring of target analytes in different technological areas. For three decades, biosensors have been the subject of increasing research effort and now constitute a major component of mainstream analytical chemistry (1,2).