20.6 Future Developments and Associated Roadblocks

From the discussion conducted so far, it is clear that self-powered technology has tre­

mendous advantages that can potentially revolutionize the entire field of bioelectronics

gadgets. A time in the history of the human race where each biomedical device discussed

so far runs on such technology is not very far away. However, getting there would re­

quire the entire scientific community to identify the challenges that persist at each im­

plementation step. In this section, we compile some of the roadblocks ahead of us and we

shall try to provide some of our understanding of how those can be tackled to achieve the

goal of advanced medical care for all.

1. The most significant challenge associated with the self-powered biomedical device

is that it must meet all the biocompatibility requirements, especially considering

that these devices are required to be implanted inside the body. The in-vivo

conditions are especially harsh considering that the nanogenerators involve certain

configurations, which need to be shielded from such environments. Thus,

encapsulation is an extreme necessity, and materials providing such tight en­

capsulation that does not significantly degrade are required. Additionally, the

human body has a very complex structure. Therefore, flexible devices that can

handle deformations without damaging internal electronics can be a great asset.

2. The nanogenerators shall be primarily based on the piezoelectric/pyroelectric/

triboelectric effect to power the devices. Thus, ensuring that the external packa­

ging does not disrupt these devices to tap the mechanical vibrations/temperature

fluctuations. Therefore, the encapsulation layers must not be unnecessarily thick,

and at the same time, they must be able to maintain the sensitivity of the na­

nogenerators. Research has suggested that flexible polymers like PDMS and

polyimide (PI) films can serve as excellent encapsulation layers. However, the

FIGURE 20.7

(a–d) TENG-based cardiac pacemaker implanted in a pig model, (e and f) shows the associated electronics of the

TENG model and how it helps in real-time monitoring of the heart rate and (g) shows the ECG and the as­

sociated voltage generated from the TENG due to energy harvesting from the heart. Adapted with permission

[ 29]. Copyright, The Authors, some rights reserved; exclusive licensee Nature. Distributed under a Creative

Commons Attribution License 4.0 (CC BY).

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