Development of conducting paper-based electrochemical biosensor for procalcitonin detection.

In the present research, an advanced cellulose fiber paper (CFP) based biosensor is developed. This sensor is modified with nanocomposites containing poly(3,4-ethylene dioxythiophene) polystyrene sulfonate (PEDOT:PSS) as the main matrix and functionalized gold nanoparticles (PEDOT:PSS-AuNP@CFP) for the selective and sensitive detection of bacterial infection (BI)-specific biomarker procalcitonin (PCT). Scanning electronic microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction are used to characterize the PEDOT:PSS-AuNP nanocomposite. This biosensor exhibits a high sensitivity of 1.34 μA (pg mL^-1)^-1 in the linear detection ranges of 1-20×10⁴ pg mL^-1, and a 24-day life span for PCT antigen detection. Anti-PCT antigenic protein is used for immobilization for PCT quantification. The results of electrochemical response studies showed that this conductive paper bioelectrode had good reproducibility, stability, and sensitivity in physiological ranges (1-20×10⁴ pg mL^-1). Further, the proposed bioelectrode is an alternative choice for point-of-care PCT detection.