Light-dependent on/off ratio of organic photoelectrochemical transistor biosensing

Organic electrochemical transistors (OECTs) possessing controllable on/off ratio (Ron/off) has long been pursued but remains challenging. Till now, few solutions to this problem are well established. Innovative light-material interactions have seen a tremendous growth in diverse electronic applications, but its possibility in Ron/off modulation has not been studied. This study addresses the challenge by the technique of organic photoelectrochemical transistor (OPECT), which is represented by metal-organic framework (MOF) derivative Ce-doped ZnIn2S4 (Ce-ZIS) gated poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) channel upon proper light impact. Interestingly, the interplay between light and Ce-ZIS could appropriately alter the device physics, rendering the light-dependent Ron/off for better transduction of biosensing signal within a fixed VG window. Biologically interfacing with a non-linear hybrid chain reaction directed dendritic DNA superstructure, the device has been shown possible for detection of microRNA-25 with good performance.