Piezoelectric crystal for sensing bacteria by immobilizing antibodies on divinylsulphone activated poly-m-aminophenol film

A polymer sorbent formed at the surface of gold-plated piezoelectric crysta l by anodic oxidation of m-aminophenol was investigated by voltammetric, FT IR techniques for antibody coupling after activation by divinylsulphone. A novel film with increased capacity for immobilizing antibodies was obtained using phloroglucinol to modify poly-m-aminophenol via divinylsulphone. Com pared with the dip-coating methods using polyethylenimine and (gamma-aminop ropyl)trimethoxysilane, this new technique gave more reproducible results f or the immobilization of antibody from sample to sample due to the improved homogeneity and reproducibility of the coating. With present modification method, a piezoelectric immunosensor was developed for the detection of Sal monella enteritidis. A detection limit of 1 x 10(5) cells ml(-1) and an ass ay time of 25 min were achieved. (C) 2000 Elsevier Science B.V. All rights reserved.