longevity, and poor repeatability. In this direction, Liu et al. [49] recently published

an MXene-based microfluidic biosensor for continuous multicomponent whole blood

analysis. The fabrication approach combines Ti3C2Tx–MXene/SPE with a low-cost mi­

crofluidic device. The MXene/SPE electrode measured creatinine, while the urease/

MB–MXene/SPE electrode recognized urea and uric acid. Three important biomarkers

are used to detect serious kidney impairment and the requirement for hemodialysis: urea,

UA, and Cre. The developed electrochemical biosensor enabled excellent sensitivity and

selectivity simultaneous multi-component measurement of urea, UA, and Cre in whole

blood. Ti3C2Tx–MXene was created utilizing a wet etching technique with HF etchant.

The EIS of SPE revealed a well-defined semicircle with an interfacial resistance of 372.71,

which nearly vanished after SPE was changed with MXene, indicating that the Ti3C2Tx

had a high electron transfer capacity. When MB was immobilized on the MXene/SPE, the

charge transfer resistance was unaltered. After immobilizing urease on it, the resistance

increased to 963.41, revealing that the enzyme that restricts the transfer of electron

pathway was successfully immobilized.

15.5 Conclusions and Future Perspectives

MXene is a versatile 2D nanomaterial that can significantly improve the mechanical, elec­

trical, and thermal properties of polymers. A MXene has very significant hydrophilic

properties, which makes it very suitable for the preparation of nanocomposites. However,

owing to the macromolecular structure of the polymer, the mixing effect of MXene in the

polymer matrix still needs to be improved. As a result, in situ polymerization mixing can be

used to make MXene/polymer nanocomposites. This solution is ideal for thermosetting and

linear polymers that can be polymerized at low temperatures and blended with MXene.

MXenes are opening up a new route for the production of conducting composites with

metallic conductivity, which could improve the sensing capabilities of amperometric en­

zymatic biosensors, thanks to direct charge transfers between MXenes and heme-based

redox proteins. This finding offers up new possibilities for MXene-based biosensors

and biofuel cells that use additional redox enzymes that can transmit direct charge.

Furthermore, MXenes’ ability to adsorb redox enzymes in 2D planes should be advanta­

geous in biofuel cell applications since enzyme orientation would be less important in such

a system, resulting in significantly greater electrochemically active surface areas of biofuel

cell electrodes. MXenes have the drawback of being only available in very small sheets (up

to 1 m in length and breadth).

References

1. S. Li, L. Ma, M. Zhou, Y. Li, Y. Xia, X. Fan, C. Cheng, H. Luo, New opportunities for

emerging 2D materials in bioelectronics and biosensors, Current Opinion in Biomedical

Engineering, 13 (2020) 32–41.

2. A. Chortos, J. Liu, Z. Bao, Pursuing prosthetic electronic skin, Nature Materials, 15 (2016)

937–950.

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