ORGANIC CHARGE-TRANSFER COMPLEX BASED PRINTABLE BIOSENSOR

This paper describes the preparation of an organic charge transfer com plex (CTC) based printable enzyme electrode. CTC crystals were prepare d by mixing TCNQ powder with TTF solution (in acetonitrile). Glucose o xidase (GOD) was adsorbed at the CTC crystal surface in a monolayer. A printable paste was prepared by mixing GOD-adsorbed crystals with a b inder and a solvent. This paste was applied to an electrode cavity and vacuum dried. A thin layer of gelatin was cast on the paste filled dr ied electrode, and crosslinked with glutaraldehyde in the dry conditio n. The sensors were fixed in a flow injection system, and continuously polarized at 0.15 V and 37 degrees C, and the samples were automatica lly injected every 30 min. The developed sensors produced a huge respo nse current with an extended linear range of detection (0 - 100 mM) an d the response was unaffected by the presence of normal oxygen in the buffer solution. The sensor showed excellent stability. The performanc e of the sensors was significantly influenced by the binder used. (C) 1996 Elsevier Science Limited