We demonstrate a proof-of-concept sensor for detection lactate using a CBPE.<br/>Using a bipolar configuration of lactate detection allows 2 key benefits compared to traditional enzyme sensors. First is the separation of the sample and measurement compartment help mitigating common interferences, which may compromise the measured signal. Second, by relying on potentiometric changes due to reduction/oxidation of the redox probe modified enzyme, the signal is independent to surface area, and can be used for continuous detection of lactate by “resetting” the bipolar electrode. To demonstrate this, we show the ability to reverse the electrode polarity, allowing for continuous detection.<br/>The bipolar electrode is composed of a lactate sensitive potentiometric sensor using redox-probe, amine reactive phenazine ethosulfate (arPES), modified lactate dehydrogenase and Prussian blue deposited gold disk electrode. The Ag/AgCl electrode is placed in an external compartment to maintain the potential in a sensing compartment based on the ratio of Prussian blue/white deposited bi-polar electrode. Electrical communication between these two electrodes is thus maintained through the faradaic reactions based on the equilibrium of Ag and Cl<sup>-</sup> in the reference compartment, and the ratio of Prussian blue to Prussian white on the bi-polar electrode. Lactate is measured using different electrode surface areas ranging from 3mm diameter 10µm diameter gold disk electrode. We demonstrate the ability to measure sweat physiological range of lactate, as shown in the figure below, as well as the ability to avoid common interference such as acetaminophen, and ascorbic acid when introduced to the sensor.

Development of a closed bipolar electrode (CBPE) based enzyme sensor for detection of lactate using microelectrodes

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.