Highly Sensitive Fentanyl Detection Based on Nanoporous Electrochemical Immunosensors

Rapid and accurate detection of fentanyl (highly potent opioid) is a critical importance due to current opioids crisis worldwide. We report the highly sensitive detection of fentanyl utilizing the synergetic effect of nanoporous silicon as a substrate with a high interfacial area and specific antibody functionalization of nanoporous silicon. The electrochemical sensor consists of gold working electrode (WE) and counter electrode (CE) deposited on nanoprous silicon, antibodies immobilized between these electrodes, and an Ag/AgCl reference electrode (RE). Square wave voltammetry (SWV) was used as an electrochemical transduction method. The detection limit was determined as 6 and 11.5 ng/mL for specific peak (fentanyl signature) in phosphate buffer (PB) and human sweat, respectively. A future goal of this study is to develop a wearable sweat sensor array for rapid and on-site detection of multiple opioids with analytical sensitivity comparable with laboratory tests.