Organic photoelectrochemical transistor detection of tear lysozyme

Abstract

Rational utilization of rich interplay between light and materials taking place in an organic electrochemical transistor (OECT) is emerging and gaining more interest from the scientific community. Light modulation is expected to realize the advanced organic photoelectrochemical transistor (OPECT) with better performance. A tear holds great potential for biodetection as it contains many biomarkers of physiological importance. In this work, we introduce a novel OPECT towards detection of a tear biomarker, which is demonstrated by assembling CdS quantum dots (QDs) onto a metallic Ti wire followed by assembly of specific aptamers toward a model target of lysozyme. Upon light illumination, the alternation of the potential drop at the CdS QDs/Ti gate electrode surface induced by biorecognition could intimately change the doping/de-doping status of the poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), resulting in amplified channel current signals for sensitive lysozyme detection. This work provides a new and simple platform for detection of a tear biomarker and beyond.