Biofluid-compatible assay for cytokine tracking (BIOACT) towards point-of-care diagnostics

Point-of-care diagnostics are essential for managing diseases and disorders in resource-limited settings; however, their translation is limited by analytical performance in complex biofluids, particularly whole blood. Electrochemical immunosensors offer a solution for affordable, portable, quantitative PoC testing. Yet their accuracy is compromised by matrix-dependent distortions arising from viscosity, cellular interference, and endogenous electroactive species. Immunoprofiling of cytokine signatures is crucial for distinguishing latent and active tuberculosis (TB), particularly in high-burden, decentralized settings. We present BIOACT (Biofluid-Compatible Assay for Cytokine Tracking), an electrochemical biosensor platform engineered to concurrently quantify IL-10 and TNF-α, two immunologically antagonistic cytokines implicated in TB progression. This platform enables multiplex cytokine detection in whole blood (WB) and plasma, utilizing a calibration model applicable to both fluids, while demonstrating sensitivity across a detection range, with recovery rates conforming to CLSI standards. By providing robust, reproducible cytokine detection across relevant biofluids, BIOACT offers a scalable solution for point-of-care applications. With potential for multiplexed cytokine panels and integration with portable electronics, BIOACT is a point-of-care tool in resource-limited settings. It achieves plasma-level accuracy in whole blood, facilitating testing in resource-constrained environments. Results establish a framework for compensating matrix effects in biosensing and enabling multiplexed PoC platforms across settings.