Biodegradable piezoelectric devices hold great promise in on-demand transient bioelectronics. Existing piezoelectric biomaterials, however, remain obstacles to the development of such devices due to difficulties in large-scale crystal orientation alignment and weak piezoelectricity. Here, we present a strategy for the synthesis of optimally orientated, self-aligned piezoelectric γ-glycine/polyvinyl alcohol (γ-glycine/PVA) films via an ultrasound-assisted process, guided by density functional theory. The first-principles calculations reveal that the negative piezoelectric effect of γ-glycine originates from the stretching and compression of glycine molecules induced by hydrogen bonding interactions. The synthetic γ-glycine/PVA films exhibit a piezoelectricity of 10.4 picocoulombs per newton and an ultrahigh piezoelectric voltage coefficient of 324 × 10 −3 volt meters per newton. The biofilms are further developed into flexible, bioresorbable, wireless piezo-ultrasound electrotherapy devices, which are demonstrated to shorten wound healing by ~40% and self-degrade in preclinical wound models. These encouraging results offer reliable approaches for engineering piezoelectric biofilms and developing transient bioelectronics.

中文翻译：

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基于高度自对准压电生物膜的柔性、可生物降解超声波无线电疗装置


可生物降解的压电器件在按需瞬态生物电子学领域具有广阔的前景。然而，现有的压电生物材料由于难以大规模晶体取向排列和弱压电性，仍然阻碍了此类器件的发展。在这里，我们提出了一种在密度泛函理论指导下，通过超声辅助过程合成最佳取向、自对准压电γ-甘氨酸/聚乙烯醇（γ-甘氨酸/PVA）薄膜的策略。第一性原理计算表明，γ-甘氨酸的负压电效应源于氢键相互作用引起的甘氨酸分子的拉伸和压缩。合成的γ-甘氨酸/PVA薄膜表现出10.4皮库伦/牛顿的压电性和324×10的超高压电压系数−3伏特米每牛顿。这些生物膜被进一步开发成灵活的、可生物吸收的、无线压电超声电疗设备，经证明可将伤口愈合时间缩短约 40%，并在临床前伤口模型中自我降解。这些令人鼓舞的结果为工程压电生物膜和开发瞬态生物电子学提供了可靠的方法。