Highly sensitive and stable glucose sensing using N-type conducting polymer based organic electrochemical transistor

Abstract

Glucose sensors have emerged as indispensable tools in monitoring glucose concentrations, enabling individuals to take proactive measures in managing their health effectively. Organic electrochemical transistors (OECTs) have emerged as promising platforms for glucose sensing, offering inherent advantages, such as stability in aqueous environments, low operating voltage requirements, and remarkable sensitivity. In this study, we present the development of an OECT-based glucose sensor using a N-type conducting polymer poly(benzimidazobenzophenanthroline) (BBL) as the active layer. BBL exhibited high performance and stability in an aqueous electrolyte, making it an ideal candidate for glucose sensing applications. By incorporating ferrocene (FC) as an electron mediator and immobilizing glucose oxidase (GOx) on the gate electrode, we achieved remarkable sensitivity and linearity within the glucose concentration range relevant to typical blood sugar levels. Stability tests revealed consistent performance over multiple cycles and continuous stressing, indicating the sensor's long-term stability and reliability. Additionally, we investigated the role of FC through electrochemical absorption and Raman shift spectra, providing insights into the glucose sensing mechanism. Moreover, the glucose sensor demonstrated promising performance on a flexible PET substrate, highlighting its versatility for practical applications in glucose sensing and beyond.