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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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Review—Catalytic Electrochemical Biosensors for Dopamine: Design, Performance, and Healthcare Applications
Dopamine is an essential neurotransmitter for daily cognitive functions controlling many neurophysiological processes including memory, cognition, and physical control. Development of analytical methods and sensors to detect dopamine is important for health monitoring and neurological research. This review provides an overview of recent advances in the development of electrochemical catalytic biosensors based on enzyme and enzyme-mimetic materials and discusses their potential applications for measurements of dopamine in biological fluids. The first part of the review summarizes and critically assesses the different types of enzymes and enzyme mimetic materials that can be used to catalytically convert dopamine, followed by a discussion of the biosensor’s fabrication, key design parameters, and detection mechanism on various electrode platforms ranging from single-use screen-printed electrodes to microneedles and implantable microelectrodes. The second part provides examples of measurements of dopamine in biological samples, including saliva, urine, serum, cell cultures, and brain tissue. We conclude with a summary of advantages and limitations of these devices in the clinical field, and an outlook to future research towards the implementation and broader adoption of electrochemical biosensors in neurophysiology, pharmacology, and the clinical field.
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- Award ID(s):
- 2042544
- PAR ID:
- 10500096
- Publisher / Repository:
- The Electrochemical Society
- Date Published:
- Journal Name:
- ECS Sensors Plus
- Volume:
- 3
- Issue:
- 2
- ISSN:
- 2754-2726
- Format(s):
- Medium: X Size: Article No. 020601
- Size(s):
- Article No. 020601
- Sponsoring Org:
- National Science Foundation
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