measuring and stimulating several physiological parameters is crucial for powerful map­

ping capacity. Such bioelectronic devices comprise temperature, pH, and mechanical strain

sensors, optical stimulators, and thermal/electrical actuators. Multifunctional sensor array-

based bioelectronic devices have a great deal of promise to realize non-invasive biomedical

implants. In addition, these devices could be used for epidermal electronics and provide

data to evaluate disease and clinical monitoring.

3.5 Emerging Challenges and Future Prospective

Bioelectronics applications of 2D materials face several obstacles, despite the considerable

progress achieved in the synthesis and processing of these materials for electrical ap­

plications. To be compatible with soft tissues, bioelectronic devices need materials that

are both robust and flexible. The material’s biocompatibility, shape conformity, me­

chanical, electrical, optical, and thermal properties must be taken into account while

developing a bioelectronic device. The performance of 2D materials–based bioelectronic

devices also depends on the synthesis protocol of 2D materials. It is emergent to hunt

easy and green synthesis protocols to develop 2D materials having suitable interfaces

compatible with biomolecules and tissues. To attain this aim, researchers should focus

their efforts on easy surface modification of 2D materials using targeted molecules. It is

also critical to note that certain 2D materials (MoS2, BPs, and MXenes) have unacceptable

interfacial stabilities. Therefore, the antioxidant properties of these materials must be

improved via interface protection strategies. Such improvements result in the utilization

of these materials for long-term in-vitro and i- vivo exposure to physiological fluids.

Another challenge is the scaling-up of present single prototype devices to array-level or

batch-level devices. This significantly demands the synthesis of wafer-scale, highly uni­

form, and defect-controlled 2D materials except for graphene (which has been un­

successful until now). In addition, it is still difficult to prevent the deterioration of these

devices due to contamination during processing. The mechanical and chemical stability of

these materials may need future development of specific patterning, modification, or

packaging processes. Furthermore, a variety of bioelectronic devices may be integrated to

create multifaceted bioelectric systems capable of performing a wide range of tasks.

Consequently, greater efforts are required to make 2D materials compete with conven­

tional bioelectronic materials. Additionally, the identification of individual biomolecules

amid a vast number of interferents is still difficult for 2D materials–based bioelectronics.

It is also important to pay attention to 2D materials–based bioelectronics that possesses

specific bio-interactions on targeted cells, and even pathogens. Hence, the practical ap­

plication potential in therapeutic domains may be pushed ahead.

References

1. B. Wang, Y. Sun, H. Ding, X. Zhao, L. Zhang, J. Bai, K. Liu, Bioelectronics-related 2D ma­

terials beyond graphene: Fundamentals, properties, and applications, Adv. Funct. Mater. 30

(2020). https://doi.org/10.1002/adfm.202003732

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