Abstract:
Implantable electronics hold enormous clinical potential for diagnosis and treatment of neurodegenerative and cardiac diseases and abnormalities. Transient devices are attractive alternatives to conventional silicon electrodes, as they can provide short-term electrical stimulation/recording followed by complete device degradation, mitigating the need for removal surgeries. Packaging transient metals is inherently challenging as they degrade upon contact with aqueous conditions. Development of new transient metal packaging strategies is a critical step toward transient device development. In this fundamental work, a solvent-free compression molding approach to encapsulate magnesium, a resorbable metal, in silk fibroin protein is reported. Silk fibroin was selected because of its processing versatility, desirable mechanical properties, compatibility with biological environments, and controllable degradation behavior in aqueous environments. The silk/magnesium composites were fabricated via compression molding, followed by water annealing to modify the secondary structure of the silk protein matrix to tune physical properties. Transient composite properties as a function of water annealing time are presented, which elucidate synergies between silk physical properties and degradation kinetics of the encapsulated magnesium, information useful in the design of multifunctional, transient metal-based constructs.
摘要:
植入式电子器件在诊断和治疗神经退行性疾病和心脏疾病和异常方面具有巨大的临床潜力。瞬态器件是传统硅电极的有吸引力的替代品,因为它们可以提供短期电刺激/记录,然后是完全的设备退化,减轻移除手术的需要。封装瞬态金属固有地具有挑战性,因为它们在与水性条件接触时降解。开发新的瞬态金属封装策略是迈向瞬态器件开发的关键一步。在这项基础工作中,无溶剂压缩成型方法来封装镁,一种可吸收的金属,丝素蛋白中有报道。丝素蛋白之所以被选中是因为其加工的多功能性,理想的机械性能,与生物环境的兼容性,和在水环境中的可控降解行为。丝/镁复合材料是通过压缩成型制备的,然后进行水退火以修饰丝蛋白基质的二级结构以调节物理性质。给出了作为水退火时间函数的瞬态复合材料性能,这阐明了丝的物理性质和包封镁的降解动力学之间的协同作用,对多功能设计有用的信息,瞬态金属基结构。