Research Interests: Microbial electrophysiology and bioelectronics.Job Interests: Academia, post-doc, industry R&D.
Tom J. Zajdel is a PhD Candidate in Electrical Engineering at UC Berkeley, where he designs microsystems that interface with bacterial cells for biosensing. During graduate school, he co-developed "EE40LX: Electronic Interfaces" with Professor Michel Maharbiz, a massive open online course that teaches basic circuit principles, reaching over 80 thousand students worldwide. He is a recipient of the Berkeley Chancellor's Fellowship and the NSF Graduate Research Fellowship. He completed his BS in Electrical and Computer Engineering from The Ohio State University in 2012.
Tethered Bacteria-Based Biosensing [BPN853]
The objective of this work is to construct a low-power biosensor suitable for use in microrobotics applications. The target detection limit is 10 parts per billion and the target response time is on the order of 30 seconds or less. When sensing dissolved analytes, speed, sensitivity, and size are subject to fundamental physical constraints set by diffusion noise. The chemical receptors and pathways used by E. coli during chemotaxis - the cellís motility response to chemicals in the medium - are known to approach the fundamental limits on response time and sensitivity for a cell of its volume, roughly 1 fL. Despite this natural capacity, no modern engineered biosensing system approaches these limits in the same deployable size as a bacterium. We propose to monitor chemotactic motor switching in an array of E. coli cells, each tethered by one flagellum, to estimate the concentration of bioanalytes in their surroundings. We have fabricated microelectrode arrays to monitor solution impedance perturbations as tethered bacterial cells rotate between electrodes, which will eventually allow for the monitoring of bacteria without being tethered to a microscope.