Development of an innovative flexible paper-based methanol fuel cell (PB-DMFC) sensing platform – Application to sarcosine detection

This work describes for the first time a paper-based direct methanol fuel cell platform (PB-DMFC) that functions as an energy source and biosensor, assembled on simple paper substrate point-of-care (POC) applications, targeting sarcosine proof-of-concept. Specifically, strip was developed from square of Whatman paper, acting substrate. The treated with impermeable agent (paraffin solution) supported all device components, including electrolyte (Nafion®), anode electrode (carbon black Pt/Ru), cathode Pt), current collectors (silver edges). All described components formed flexible single layer operated in completely passive mode by adding few microliters solution side using atmospheric oxygen side. obtained had stable electrical signal average OCV value 0.45–0.55 V maximum power density 20–50 µW/cm2, depending concentration used (0.5 M–2 M). A sensing built situ electropolymerization 3,4-ethylenedioxythiophene (EDOT) pyrrole (Py) monomers. PB-DMFC/biosensor calibrated at room temperature buffer healthy human urine showed linear responses 1.0 × 10−7 to 10−3 M detection limit 6.6 10−8 M. Selectivity studies evidenced signals changing within 1–10%, both positive negative directions. Results good reproducibility. Overall, results demonstrate self-sufficient biosensor consisting innovative strip. concept can open new horizons massification biosensors even places shortage.