A Molecular bio-wire based multi-array biosensor with integrated potentiostat

Abstract

One of the important factors determining the sensitivity of any biosensing system is successful integration of bio- molecular transducers with peripheral signal processing circuitry. In this paper we present an architecture of a multi-array biosensor that integrates molecular bio-wires based immunosensor with a multi-channel potentiostat array. The biosensor operates by converting binding events between antigen and antibody into a measurable electrical signal using polyaniline nanowires as a transducer. The electrical signal is measured using a multichannel potentiostat where each channel comprises of a semi- synchronous SigmaDelta modulator. Measured results using a fabricated potentiostat array demonstrate sensitivity down to 50 femtoampere range which makes it ideal for detecting pathogens at low concentration levels. Experiments using the biosensor array specific to Bacillus Cereus bacterium validate the functionality of the platform in detecting the pathogen at different concentration levels.