Conducting Biomaterials for Nerve Regeneration

描述（由申请人提供）：在美国，每年有超过一百万人遭受严重的周围神经损伤，每年进行20,000例手术来修复被切断的周围神经。神经引导通道（NGCs）是一种中空的导管，用于连接周围神经的大间隙。目前的NGC材料有许多缺陷，这些缺陷经常妨碍它们的使用或导致程序失败。因此，需要一种新的生物材料来促进神经再生，以制备改良的神经干细胞。

DESCRIPTION (provided by applicant): In the U.S. more than one million people suffer serious peripheral nerve injuries every year and 20,000 procedures are carried out annually to repair severed peripherals nerves. Nerve guidance channels (NGCs) are hollow conduits used to bridge large gaps of severed peripheral nerves. Current NGC's materials have many drawbacks that often preclude their use or cause failure of the procedure. Therefore, new biomaterials that actively promote nerve regeneration are needed for the fabrication of improved NGCs. Electrically conducting biomaterials are of interest because they can be used to deliver electrical stimulation to responsive cells like osteoblasts, endothelial cells, and neurons. Polypyrrole (PPy) is an electrically conducting polymer that is not cytotoxic and has been demonstrated to favor the regeneration of damaged peripheral nerves in rats. Because PPy is a semiconductor, it can be used to deliver electric stimuli to cultured cells, accelerating their growth, migration and proliferation. Unfortunately PPy is not biodegradable, and NGCs made of PPy must be removed from the body upon healing, requiring a second surgery and causing additional site morbidity. Moreover, PPy, like most conducting polymers, is insoluble and infusible, and has poor mechanical properties. Therefore, it is very difficult to process it into the necessary form. Together, these properties limit the practical applications of PPy in tissue engineering. The objective of this project is to make a biodegradable form of PPy that can be processed from solution, and to test its properties as a support for the regeneration of severed nerves. During the Phase I project TDA successfully prepared a PPy-based biomaterials that are electrically conducting, can be processed from solution and support well neuron growth in vitro.