Abstract
World-wide lung cancer is one of the most frequent categories of cancer. Early detection can substantially reduce the numbers significantly. Biosensors are the most promising solution towards early detection of deadly diseases compared to other techniques. In this study, we report the development of an impedance-based sensor based on carbon porous nanopowder (CPN) for the detection of isoprene, a volatile organic compound (VOC) present in the breath, thereby acting as a breath biomarker for lung cancer detection. The CPN is characterized using advanced analytical techniques including XRD, FTIR, UV–Vis spectroscopy, SEM, XPS and BET gas adsorption analyzer. The sensing is performed using printed circuit board (PCB) electrode via Electrochemical Impedance Spectroscopy (EIS) within the isoprene concentration range 10 ppb–134 ppb at room temperature in the frequency range 0.1 Hz - 0.1 MHz, with a small signal amplitude of 10 mV. The sensor has a limit of detection (LoD) of 10 ppb, a sensitivity of 2.4 Ω/ppb/mm2, and good selectivity for isoprene among other VOCs present in breath (acetone, ethanol, toluene, water vapors and nitrogen). The response time of around 10 s is obtained. The hypothesis proposed in this study for the detection of isoprene is also confirmed using the z-view simulation modelling across various concentrations. The developed sensor surpasses various prior isoprene detection technologies, making it ideal for the detection of isoprene.
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•Lung cancer is the main cause of cancer-related fatalities worldwide.•CPN is used for impedance-based sensing of Isoprene (a lung cancer biomarker).•The sensor showed good sensitivity (2.4 Ω/ppb/mm2) & high selectivity.•The LoD is found to be 10 ppb with response time of 10 s at room temperature.