Electrochemically Engineered PEDOT:PSS/MXene Composite Electrode for the Label‐Free Procalcitonin Detection

ABSTRACT Procalcitonin (PCT) serves as a valuable yet challenging biomarker for bacterial infections, with conventional detection methods constrained by prolonged assay durations. Electrochemical techniques provide a faster and more straightforward alternative, though they face challenges such as electrode fouling and limited sensitivity and selectivity. To address these issues, we developed a sensor using highly conductive 2D material, i.e. Ti 3 C 2 T x MXene combined with poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS), serving as an ideal microenvironment for the direct immobilization of PCT antibody, with a bovine serum albumin (BSA) coating to provide antifouling activity. The resulting BSA/Ab‐PEDOT:PSS/MXene‐based sensor is characterized with a wide PCT detection range (25–250 pg mL −1 ) and gained low detection limit (4.4 pg mL −1 ). The sensor shows promise as a rapid, simple tool for diagnosing bacterial infections or sepsis, enabling timely diagnosis and improved patient outcomes.