Conducting paper based sensor for cancer biomarker detection

We report results of studies relating to the fabrication of a paper based impedimetric biosensor using poly (3,4ethylenedioxythiophene):poly (4-styrene sulfonate) (PEDOT:PSS) modified Whatman paper. The layer-by-layer assembly of PEDOT:PSS deposited on the paper substrate results in the formation of a stable, conductive and homogenous film. The film has been characterized using Fourier transfer Infrared spectroscopy and scanning electron microscopy. This conducting paper platform has been used for the conjugation of anti-carcinoembryonic antigen (CEA) protein for quantitative estimation of CEA, a cancer biomarker that is frequently used in detection and monitoring of cancer. The results of the electrochemical impedimetric response studies indicate that the fabricated paper electrode can be used to estimate CEA in the range from 6-20 ngmL-1, has sensitivity of 3.6 Ω mL ng-1 with a lower detection limit of 2.68 ng mL-1.