HF-Sensor: A non-invasive biosensor system for heart failure diagnosis and monitoring at the point-of-care

Heart failure (HF) is a major public health challenge, contributing to high morbidity, mortality, and significant economic burden worldwide. Early diagnosis and accurate risk stratification are critical for improving patient outcomes and guiding clinical decisions. N-terminal pro-B-type natriuretic peptide (NT-proBNP) is a well-established blood biomarker of ventricular overload, widely used for diagnosing HF and assessing its severity. Beyond diagnosis, NT-proBNP provides valuable prognostic insights into treatment response and can predict adverse cardiovascular events, such as HF-related hospitalizations and mortality, thus playing a key role in personalized care and therapeutic management. Despite its clinical significance, current CE/FDA-certified methods for NT-proBNP measurement face critical limitations, particularly in point-of-care settings and for ongoing, minimally or non-invasive monitoring. These constraints hinder the ability to perform remote (e.g. community medical clinic) monitoring-a crucial capability for revolutionizing heart failure management. To address this challenge, we report the development and proof-of-concept validation of an ultrasensitive (compared to gold standard enzyme-linked immunosorbent assays), miniaturized electrochemical biosensor for fast and minute sample detection of NT-proBNP in tears from a well-characterized cohort of heart failure patients. Correlation analysis of NT-proBNP concentrations in tear fluid and blood plasma/serum, together with key clinical parameters, demonstrates that tear fluid is a promising non-invasive matrix for heart failure diagnosis and continuous monitoring in point-of-care settings. This approach provides a transformative pathway to advance heart failure management by enabling remote, point-of-care diagnostic monitoring outside of centralized hospitals and laboratories.