(Invited) A Chemiresistive Glucose Sensor Based on Polyaniline Nanowire Network

A simple fabrication technique of a low cost and disposable glucose sensor is proposed and demonstrated.  The sensor consists of an inkjet-printed polyaniline nanowire network pattern as a chemiresistive sensing material and glucose oxidase with metallic nanoparticles as enzyme and catalyst for detecting glucose.

In this work, we propose the use of catalytic nanoparticles and glucose oxidase (GOx) in conjunction with polyaniline nanowires for the development of a printable glucose sensor that is simple, low cost and manufacturable on a large scale.  The working principle is as follows: glucose oxidase converts glucose into to gluconolactone and in the process releases hydrogen peroxide as a byproduct.  Hydrogen peroxide reacts with the catalytic nanoparticles to produce hydroxide ion resulting in an increase in pH.  Since the conductivity of polyaniline is pH sensitive, any production of hydrogen peroxide will lead to an increase in resistance of the polyaniline.  Hence the concentration of glucose can be determined by observing the change in the conduction current through the polyaniline-based chemiresistor.

Polyaniline nanowires were chemically synthesized and printed on a PET film by inkjet printing.  Subsequently, catalytic nanoparticles and glucose oxidase were deposited and dried on the patterned polyaniline nanowires.  The printed sensor was tested with glucose and the conduction current change was observed.  The concept demonstrated in this work can potentially lead to a fully printed biosensor.