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High-Resolution Biochemical Activity Measurements with Commercial Transistors
Published
Author(s)
Seulki Cho, Son T. Le, Curt A. Richter, Arvind Balijepalli
Abstract
We demonstrate that single-gated, commercially-sourced, field-effect transistors (FETs) operated with a lock- in amplifier (LIA) under closed-loop control can achieve an average pH resolution of 9x10^-4. This performance represents an 8-fold improvement over previous FET measurements. The measurement sensitivity was found to be 56 mV, consistent with the Nernst potential at room temperature. The precision of our approach makes it ideally suited for sensitive bioanalytical measurements. We show that the technique can be applied to measure the therapeutic efficacy of small polypeptide molecules that regulate enzymes implicated in Alzheimer's disease.
Cho, S.
, Le, S.
, Richter, C.
and Balijepalli, A.
(2020),
High-Resolution Biochemical Activity Measurements with Commercial Transistors, Proceedings of Micro Total Analysis Systems 2020, Online, CA, US, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=930772
(Accessed October 8, 2025)