Polyaniline-graphite on cellulose substrate: a flexible, low-cost, use-and-throw sensor for glucose concentration detection

Polyaniline-graphite (PANI-Graphite) composite deposited on cellulose paper substrate has been studied for the development of a glucose biosensor kit. Thin graphite layers were deposited by pencil graphite on one side of the commercially available cellulose paper substrate, and upon that the layer of PANI was deposited through a physical vapor deposition technique. The physical characterizations of the prepared samples were carried out using X-ray diffraction analysis, ultraviolet (UV)-visible absorption spectroscopy, scanning electron microscopy, and electrical transport measurements. The sensing responses of glucose with different concentrations were studied by observing the resistive changes due to glucose interaction. The analysis of sensor studies shows a nearly linear response with a sensitivity of 18.78 mu A(mg/dL)(-1) cm(-2) for the variation of glucose concentration. The limit of detection has been obtained as 1.6 mg/dL. The results indicate that PANI-Graphite on cellulose would be a potential candidate for using it as an active material for glucose concentration detection and it would find a profound interest because of its very lightweight, low cost, the flexibility of a paper-based kit, and is a biodegradable one.