Semiconductive biocomposites enabled portable and interchangeable sensor for early osteoarthritis joint inflammation detection

Early osteoarthritis (OA) joint inflammation detection is crucial for effective diagnosis and treatment. Thus, regular screening of OA is highly recommended, especially for the higher-risk population. However, the current OA biomarker detection methods are based on laboratory testing, which is low efficiency and high cost, and there is no point of care (POC) method available. In this work, we synthesized a biocomposite thin film in which TNF-a antibody (Abs) was covalently crafted on the PANI conjugating skeleton to form the semiconductive Ab-PANI composites, as the TNF-a acceptor and also the signal amplifier. The PANI structure was altered during the adsorption with the UV–visible spectroscopy and also caused the electrochemical impedance spectroscopy (EIS) signal change by monitoring the TNF-a adsorption behavior. A complex EIS analysis quantified the concentration of TNF-a, and the detection method was trained in a wide concentration range of TNF-a of PBS buffer solution. This screen-printed PANI-Ab sensor (SPAS) was further evaluated with the mice serum samples showing compatible accuracy and precision in comparison to conventional enzyme-linked immunosorbent assay (ELISA). Finally, the parallel accuracy validations on SPAS arrays indicate no significant difference in both precision and accuracy of measurement, which is suitable for the future interchangeable application of long-term inflammation monitoring.