(Invited) Development of Fuel Cell-Based Electrochemical Micro Gas Sensor for Monitoring Anesthetic Organic Compounds

Abstract

Surgical procedures require administering anesthetic agents in concentrations between 0.5 and 2.0% to maintain a patient's sedation. Maintaining the concentration of the anesthetic agents within the specified range is vital in preventing overdose or awareness during procedures. There is an increasing demand for developing an accessible, low-cost, wearable anesthetic sensor to ensure patient and personnel safety. This work focuses on fulfilling the clinical demand by developing a transcutaneous biosensor device that can accurately measure and monitor the concentration of anesthetic agent isoflurane (1-chloro-2,2,2-trifluoromethyl difluoromethyl ether) in the human body at a lower cost per unit to address this unmet need. The approach utilizes the creative form of a micro-fuel cell sensor that is composed of a proton exchange membrane (PEM) sandwiched between two metal electrodes to measure the isoflurane excreted through the subject's skin. At the anode, the isoflurane oxidative reaction generates electrons transferred to the cathode electrode. The oxygen reduction reaction is triggered by protons moving across the PEM at the cathode. Isoflurane concentration is measured in terms of electrical signals from the electrons traveling in the external circuit that produce a current proportional to concentration. Furthermore, we investigate the impact of different catalysts, platinum-group metals (PGM) and PGM-free, on the voltage and current output. The fuel cell-based electrochemical biosensor exhibits excellent sensitivity, linearity, and a low detection limit. Higher accuracy in the ultra-low concentration range of sub 40ppm is achieved by imputing the obtained data into a principal component regression (PCR) algorithm. This work highlights an integrated microsensor to monitor transcutaneous isoflurane concentration continuously. Current research enables understanding the dynamic interaction between sensing surface area and volatile anesthetics excreted through the patient's skin. Furthermore, creating a novel approach for non-invasive wearable healthcare devices for detecting volatile organic compounds in the human body. Figure 1