Multi-sensor electronic platform for high resolution HIV antigen detection

The growing demand for rapid, accurate, and decentralized diagnostics has accelerated the developmentof point-of-care (PoC) biosensors for early disease detection. In this work, we demonstrate the detection of the HIVspecific capsid antigen p24 protein by a compact, fully electronic, and reconfigurable bioelectronic platform based onimpedance sensing. The platform integrates a multichannel array of gold interdigitated electrodes (IDEs) that can beindependently functionalized to enable multiplexing, redundancy, and statistical validation. A differential readoutarchitecture, combining transimpedance amplification with FPGA-based digital lock-in detection, ensures the higheststability over temperature and salinity fluctuations and effective rejection of common-mode errors. Experimentalvalidation demonstrated sensitive detection of HIV p24 across multiple concentrations, with a limit of detection of8.5 pg/mL. Measurements on virus isolate samples further confirmed the robustness and reliability of the platform.These results establish the system as a versatile and scalable option for next-generation PoC diagnostics, withparticular strengths in stable, multichannel, and adaptable antigen detection: thanks to the copolymer coating of thechips, reconfiguration requires only the substitution of the spotted probes, enabling applications that range from highlyspecific biorecognition elements to broader capture molecules