Real-time monitoring of a panel of inflammation biomarkers by a point-of-care sensor

When the entire world is grappling with the COVID-19 pandemic, this is an opportunity for us to use the lessons learned to be prepared for detecting, containing, and rapidly responding to and mitigating the spread of emerging infectious diseases. Hence, in this project, we have developed a novel biochip for rapid and real-time detection of infection at the point-of-care. The biochip features multiplexed detection of 4 inflammatory biomarkers using electrochemistry-based measurement technique. We have demonstrated the detection of Interleukin-6 (IL-6), the elevated levels of which is found to associate with adverse clinical outcomes and death in critically ill SARS‑CoV‑2 patients. Our design consists of 4 working electrodes (WE) for detecting 4 biomarkers, one reference electrode (RE), and one counter electrode (CE) for real-time monitoring of biomarkers. Gold nanoparticles (AuNPs) decorated multi-wall carbon nanotube (MWCNT) nanocomposite is formed on each WE to create a three-dimensional working surface, which substantially enhances the sensitivity. The Au-MWCNT functionalized WEs are immobilized with antibodies specific to the biomarkers. The protein biomarkers are selectively captured on the respective WEs depending on the protein-antibody binding and result in variations in current flow from WE to CE. The sensor demonstrates a sensitivity of 9.128 uA uM-1 cm-2, a limit of detection of 2.6 femtomolar, and a response time of only 2 seconds. Our research holds substantial societal benefit because it will reduce the time to detection (which is especially critical in an under-resourced setting) and save lives. Our device has huge potential to manage future pandemics through early diagnosis and timely treatment and isolation.