Designing Bimetallic Sensors for Acetone Biomarker Detection

The analysis of volatile organic compounds (VOCs) in exhaled breath has emerged as a rapid method for diagnosing lung diseases. The current study focuses on the computational design of bimetallic biosensors that can detect VOC biomarkers. We performed density functional theory (DFT) calculations to investigate the adsorption of acetone as a lung cancer biomarker versus interfering air molecules (N₂, CO₂, and H₂O) on Fe₂N₅P dual-atomic site embedded C60 fullerene (Fe₂N₅P/C60). Despite the impressive performance of Fe₂N₅P/C60, subsequently, we shifted to dual-doped biosensors and achieved improved detecting performance. In this respect, the bimetal sensors, namely, FeCoN₅P/C60, FeNiN₅P/C60, FeCuN₅P/C60, and FeZnN₅P/C60, are designed for their bifunctional performance toward acetone gas molecule. Our results revealed that a superior synergistic effect is obtained in the FeCuN₅P/C60-codoped system. Our findings also indicate an increase in the adsorption energy of acetone on the FeCuN₅P/C60 bimetallic sensor when exposed to interfering air molecules. The calculated work function values of the acetone/nanocage complexes revealed that all of the designed sensors are sensitive to acetone gas molecules. Furthermore, the obtained recovery time determines the relatively fast recovery of the Fe₂N₅P-based biosensors.