Biocompatibility and in vivo operation of implantable mesoporous PVDF-based nanogenerators

Abstract

The rapid developments of implantable biomedical electronics give rise to the motivation of exploring efficient and durable self-powered charging system. In this paper, we report a mesoporous polyvinylidene fluoride (PVDF)-based implantable piezoelectric nanogenerator (NG) for in vivo biomechanical energy harvesting. The NG was built with a sponge-like mesoporous PVDF film and encapsulated by polydimethylsiloxane (PDMS). After embedding this NG into rodents, a Voc of ~200 mV was produced from the gentle movement of rodent muscle. Meanwhile, no toxicity or incompatibility sign was found in the host after carrying the packaged NG for 6 weeks. Moreover, the electric output of this NG was extremely stable and exhibited no deterioration after 5 days of in vivo operation or 1.512 × 108 times mechanical deformation. This NG device could practically output a constant voltage of 52 mV via a 1 µF capacitor under living circumstance. The outstanding efficiency, magnificent durability and exceptional biocompatibility promise this mesoporous PVDF-based NG in accomplishing self-powered bioelectronics with potentially lifespan operation period.

Stretchable, Transparent, and Thermally Stable Triboelectric Nanogenerators Based on Solvent‐Free Ion‐Conducting Elastomer Electrodes

“…The STENG can convert tiny mechanical energy in the environment into electrical energy 40,51–55. In our experiment, we converted the energy of human motions into electrical energy by ICE‐iTENG.…”

Recent Progress on Piezoelectric, Pyroelectric, and Magnetoelectric Polymer‐Based Energy‐Harvesting Devices

“…An open‐circuit voltage of 0.26 V and a short‐circuit current of 0.17 µA were observed when the rat moved. After 5 days, with the device within the mouse, the voltage was stable around 0.20–0.26 V, with no signs of toxicity or biocompatibility problems . A system capable of harvesting energy from the arterial pulse on the human wrist was also reported.…”

On mechanical properties and bioactivity of PVDF-BCP composites

“…These results indicated high proliferation of the osteoblast cells, which are bone cells, in PVDF films [28], and more bioactivity in the polar PVDF phase (β-PVDF) and poled PVDF films, mainly under mechanical stimuli [29,30]. Currently, a novel generation of highly advanced PVDF-based implants has been thought and developed, as those where PVDF-based nanogenerators, that were successfully implanted/tested in rats [31], attested the applicability of PVDF for bio-applications. Furthermore, a PVDF-HA composite was also developed as an osseous implant [32].…”

“…In this way, considering previous reports where the influence of the electric charge surface on the activity of biomaterials [25] was pointed out and discussed, it is ease to intuit that piezoelectric materials can be used to catalyze biological responses. Recent studies have been conducted in order to understand the potentialities of the polyvinylidene fluoride [(C 2 H 2 F 2 ) n or PVDF] matrix composites in human implants [26][27][28][29][30][31][32]. In this way, different biological applications have been thought for PVDF polymer, leading to different synthesis technique and sample architectures, as scaffold, for example [27].…”