Medical Engineering Distinguished Seminar, Muhammad A. Alam
Field-deployed implantable and wearable sensors are transforming how we tackle global challenges like sustainable agriculture, healthcare, and water-quality monitoring. These sensors, however, operate in harsh conditions. Field-deployed potentiometric ion-selective electrodes (ISEs) operate in fluctuating ambient temperatures with rapid sensor drift, while amperometric wearable sensors must grapple with biofouling and small-volume effects. Many ambitious projects fail because intrinsic differences between the laboratory and field operations are not appreciated.
In this talk, I will discuss simple yet foundational concepts to make these sensors more dependable, including (a) the use of the Nernst principle to measure self-temperature from the voltage of paired sensors, (b) borrowing ideas from communication theory, monitor temperature to detect and correct sensor drift on the fly, and (d) reframing the transient response of Michaelis-Menten equations for finite volume micro-needles.
This method works across lab tests, greenhouses, and even in real agricultural fields, delivering precise results for months, even under harsh conditions. Our approach opens exciting possibilities for affordable, reliable sensing in real-world settings.
Biography: Professor Alam is the Jai N. Gupta Distinguished Professor at Purdue University, where his research focuses on the physics and technology of semiconductor devices operated in extreme environments. From 1995 to 2003, he was at Bell Laboratories, Murray Hill, NJ, focusing on optoelectronic integrated circuits and transistor reliability. Since 2004, Dr. Alam has authored over 300 papers on the fundamental performance limits and reliability physics of transistors, biosensors, and solar cells. He is a fellow of the IEEE, APS, and AAAS and has received numerous awards, including the 2006 IEEE Kiyo Tomiyasu Medal, the 2015 SRC Technical Excellence Award, and the 2018 IEEE EDS Education Award. Dr. Alam enjoys teaching and his web-enabled courses have reached over 500,000 students globally.
https://sites.google.com/view/alam-research-group/home
References
(2) Saha, A., Yermembetova, A., Mi, Y., Gopalakrishnan, S., Sedaghat, S., Waimin, J., Wang, P., Glassmaker, N., Mousoulis, C., Raghunathan, N. and Bagchi, S., 2022. Temperature self-calibration of always-on, field-deployed ion-selective electrodes based on differential voltage measurement. ACS sensors, 7(9), pp.2661-2670.
(2) Saha, A., Mi, Y., Shakouri, A. and Alam, M.A., 2023. In Situ Drift Monitoring and Calibration of Field-Deployed Potentiometric Sensors Using Temperature Supervision. ACS sensors, 8(7), p. 2799.
(3) Fratus, Marco and Muhammad A. Alam. "The viability of Parkinson's monitoring by microneedle patches: A theory-guided critical analysis." Applied Physics Letters 125, no. 17 (2024).
https://engineering.purdue.edu/ECE/People/ptProfile?resource_id=3171