A disulfide-carrying polymer with pendent glucose residues (poly(2-methacryloyloxyethyl D-glucopyranoside)) was obtained by using a benzyl N,N-diethyldithiocarbamoyl derivative which shows the abilities of initiation, chain transfer, and termination (iniferter). The disulfide-carrying polymer was accumulated on a colloidal Au-immobilized glass substrate, and the usefulness of the polymer as a sensing element of concanavalin A (Con A) was examined by using a UV-visible spectrophotometer with the help of surface plasmon resonance. The sensor showed a concentration-dependent specific binding of Con A with a detection limit of 1.9 nM, and furthermore, it had a very high stability at high ionic strength. The polymer-coated device examined here was not only useful as a simple biosensor chip but is also expected to expand our knowledge of interfacial phenomena by introducing various functional polymers on colloidal Au.

A disulfide-group-carrying novel iniferter (a compound which pursues initiation, chain transfer, and termination) (Cys-BDC) was prepared by coupling N,N-diethyldithiocarbamoylmethylbenzoic acid succinimidyl ester with cystamine dihydrochloride. Block copolymerization of methacrylic acid (MA) and 2-methacryloyloxyethyl D-glucopyranoside (MEGlc) was performed by successive UV-irradiation in the presence of the iniferter and N,N,N′,N′-tetraethylthiuram disulfide. The block telomer formed a selfassembled monolayer (SAM) on a gold electrode and vacuum-evaporated gold thin film, as confirmed by cyclic voltammetry and infrared reflection-absorption spectroscopy (IRRAS), respectively. The pHresponsiveness of the MA telomer block on the gold surface and silver colloid was confirmed by contact angle and ζ-potential measurements, respectively. Recognition of glucose residues in the MEGlc block by a lectin (Concanavalin A) was followed on the gold surface and silver colloid by IRRAS and turbidity measurements, respectively. Our results strongly support the usefulness of the iniferter for the preparation of various block-telomer-carrying SAMs with biorelated functions.

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