Center for Functional Nanomaterials Seminar

Chronic diseases are a major healthcare challenge with significant human and economic costs. In the U.S., the economic burden of chronic diseases has reached ~$3.8 trillion in 2017 and is expected to increase as the population ages. Mobile (handheld, wearable, implantable) sensors that can measure analytes from biofluids (e.g. sweat, saliva) have the potential to revolutionize healthcare by providing inexpensive and non-invasive disease monitoring. Another important healthcare area is early diagnostics, requiring sensors that can detect biomolecules at ultra-low (< 10-18 M) concentrations. Additionally, there are many unmet sensing needs in IoT such as agriculture and food safety that also require mobile sensors. To address these sensing challenges, we leverage physics principles and the vast expertise of the semiconductor technology to demonstrate innovative sensors that are notably superior than the current sensors. For example, we proposed and demonstrated the bipolar junction transistor (BJT) device as a significantly improved transducer in comparison to the widely used field effect transistors (FET) transducer.[1-3] The BJT based sensors are shown to be well suited for mobile applications with inherently simpler calibration (one-point), low power requirements, enhanced sensitivity and resolution. Additionally, we have demonstrated a novel reference electrode that enables measurement of analytes from solid mediums (e.g. tissue, soil), thus enabling implantable sensing applications in healthcare and IoT (e.g. agriculture, food safety). These sensing results (including application examples) will be presented. Lastly, silicon nanowire FET sensors for early diagnostic applications will be discussed. These sensors have been extensively investigated for >15 years but are hindered by large fabrication-induced sensor variability, an impediment to quantitative studies and clinical applications. We will present our approach t