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Two-dimensional (2D) layered materials that integrate metallic conductivity, catalytic activity and the ability to stabilize biological receptors provide unique capabilities for designing electrochemical biosensors for large-scale detection and diagnostic applications. Herein, we report a multifunctional MXene-based 2D nanostructure decorated with enzyme mimetic cerium oxide nanoparticle (MXCeO2) as a novel platform and catalytic amplifier for electrochemical biosensors, specifically targeting the detection of oxidase enzyme substrates. We demonstrate enhanced catalytic efficiency of the MXCeO2 for the reduction of hydrogen peroxide (H2O2) and its ability to immobilize oxidase enzymes, such as glucose oxidase, lactate oxidase and xanthine oxidase. The designed biosensors exhibit high selectivity, stability, and sensitivity, achieving detection limits of 0.8 μM H2O2, 0.49 μM glucose, 3.6 μM lactate and 1.7 μM hypoxanthine, when the MXCeO2 and their respective enzymes were used. The MXCeO2 was successfully incorporated into a wearable fabric demonstrating high sensitivity for lactate measurements in sweat. The unique combination of MXenes with CeO2 offers excellent conductivity, catalytic efficiency and enhanced enzyme loading, demonstrating potential of the MXCeO2 as a catalytically active material to boost efficiency of oxidase enzyme reactions. This design can be used as a general platform for increasing the sensitivity of enzyme based biosensors and advance the development of electrochemical biosensors for a variety of applications.
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This content will become publicly available on April 29, 2027
An Automated Electrochemistry Platform for Accelerating the Characterization of Enzymatic Electrochemistry
Enzymatic electrochemistry harnesses the selectivity of enzymes to enable electrochemical applications spanning sensing, synthesis, and energy conversion. However, the sequential nature of electroanalytical experiments limits throughput, restricting the scale at which enzyme-electrode systems can be screened. Here we demonstrate the capabilities of an automated electrochemistry platform, eLab, to increase the throughput of enzymatic electrochemistry investigations. We used the eLab to collect over 10,000 cyclic voltammograms across a large parameter space consisting of two enzyme variants (promiscuous and wild-type glucose oxidase), 20 saccharide substrates, 21 concentrations, and four scan rates, with measurements being made all in triplicate. The expansive dataset enabled rapid identification of apparent outlier behavior of wild-type glucose oxidase toward glucose, which was confirmed to arise from oxygen sensitivity through targeted manual experiments. The promiscuous variant showed negligible oxygen sensitivity, a critical advantage for applications, such as enzymatic sensors, bioelectrosynthesis, and biofuel cells. Overall, this work demonstrates how automation can be applied to accelerate discovery in bioelectrochemistry.
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- PAR ID:
- 10682111
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Electrochemistry
- ISSN:
- 2997-0571
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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