Highly sensitive and rapid MicroRNA detection for cardiovascular diseases with electrical double layer (EDL) gated AlGaN/GaN high electron mobility transistors

This study reports the development of an efficient and sensitive method to directly sense microRNA (miRNA) in high ionic strength solutions with the use of electrical double layer (EDL) gated AlGaN/GaN high electron mobility transistor (HEMT). This FET structure uses a complementary DNA probe functionalized gate electrode which is separated from the transistor channel. In this research, we focus on the detection of miRNA samples, miR-126, miR-208a and miR-21 which are biomarkers of cardiovascular diseases (CVD). The sensor has a dynamic range that is comparable to the clinically relevant concentration range with a detection limit as low as 1 fM. Selectivity of the sensor is demonstrated by evaluating sensor response at fully complementary and slightly mismatched sequences. The miniaturized sensor can be used in point of care or homecare diagnostics for rapid miRNA detection to evaluate CVDs at an early stage.