About the Seminar: 

Heart failure (HF) is a leading cause of death worldwide and continues to increase in prevalence as the general population ages. Advances in the healthcare management of heart failure have led to lower morbidity and mortality rates but require accurate diagnostics to guide the process. Current HF diagnostics require expensive equipment, centralized facilities and trained personnel and invasive sampling, marginalizing healthcare in developing countries and rural communities. New point-of-care (POC) diagnostic platforms that are portable, affordable, and use non-invasive samples can address this unmet need. Biosensors integrated into microfluidic platforms for biological sample processing offer many advantages for POC applications because they are inexpensive, portable, and easy-to-use. However, these platforms lack sensitivity, the ability to provide quantitative results, and the ability to process viscous biological samples. Electrochemical biosensors are sensitive, quantitative analytical methods popular in POC diagnostics due to the potential for inexpensive, portable instrumentation. An emerging non-invasive biological sample matrix that does not require trained personnel to collect is saliva. Recently, our team correlated concentrations of two salivary proteins (Galectin-3 and S100A7) to HF outcomes but no biosensors have been developed for measuring these biomarker levels at the POC. While saliva presents obstacles for processing in a microfluidic device, the development of a sensitive multiplexed POC biosensor for salivary biomarkers would improve healthcare management of HF. This work demonstrates an electrochemical multiplexed sandwich immunoassay based on a screen-printed carbon electrodes for the detecting the heart failure biomarkers, galectin-3 and S100A7 in pooled saliva samples. In parallel, a novel capillary driven microfluidic platform that can process varying viscosities of saliva in less than 15 minutes was developed. The proposed electrochemical immunoassay demonstrated a linear signal response in the clinically relevant range and a limit of detection of 9.66 ng/mL (galectin-3) and 39.0 ng/mL (S100A7).  The preliminary results of the integration of the biosensor into the microfluidic platform indicate the first step towards a robust and non-invasive electrochemical sensor for HF biomarkers.