Electrochemical biosensor for targeted detection in blood using aligned Au nanowires

In this work, an electrochemical biosensor using aligned Au nanowires in a micro-fluidic platform is proposed for sensitive and selective estimation of targeted species, such as cholesterol in blood. The aligned Au nanowires were modified with specific enzymes—cholesterol oxidase (COX) and cholesterol esterase (CE), using covalent chemistry to act as the working electrode. The biosensor showed a linear relationship between cholesterol level (10–60 μM) and current response, with a sensitivity of 0.85 nA/μM. Further, studies performed with higher level of interfering species usually found in blood showed a stable and selective electrochemical response.