School of Biomedical Engineering and Sciences, Wake Forest University-Virginia Polytechnic Institute and State University, Winston-Salem, NC, 27106, USA.
Department of Plastic and Reconstructive Surgery, Wake Forest Baptist Health, Winston-Salem, NC, 27157, USA.
J Mater Sci Mater Med. 2023 Nov 15;34(11):61. doi: 10.1007/s10856-023-06763-x.
Improved materials for peripheral nerve repair are needed for the advancement of new surgical techniques in fields spanning from oncology to trauma. In this study, we developed bioresorbable materials capable of producing repeated electric field gradients spaced 600 μm apart to assess the impact on neuronal cell growth, and migration. Electrically conductive, biphasic composites comprised of poly (glycerol) sebacate acrylate (PGSA) alone, and doped with poly (pyrrole) (PPy), were prepared to create alternating segments with high and low electrically conductivity. Conductivity measurements demonstrated that 0.05% PPy added to PSA achieved an optimal value of 1.25 × 10 S/cm, for subsequent electrical stimulation. Tensile testing and degradation of PPy doped and undoped PGSA determined that 35-40% acrylation of PGSA matched nerve mechanical properties. Both fibroblast and neuronal cells thrived when cultured upon the composite. Biphasic PGSA/PPy sheets seeded with neuronal cells stimulated for with 3 V, 20 Hz demonstrated a 5x cell increase with 1 day of stimulation and up to a 10x cell increase with 3 days stimulation compared to non-stimulated composites. Tubular conduits composed of repeated high and low conductivity materials suitable for implantation in the rat sciatic nerve model for nerve repair were evaluated in vivo and were superior to silicone conduits. These results suggest that biphasic conducting conduits capable of maintaining mechanical properties without inducing compression injuries while generating repeated electric fields are a promising tool for acceleration of peripheral nerve repair to previously untreatable patients.
需要改进周围神经修复材料，以推动从肿瘤学到创伤学等领域的新手术技术的发展。在这项研究中，我们开发了可生物吸收的材料，能够产生间隔 600μm 的重复电场梯度，以评估其对神经元细胞生长和迁移的影响。由聚（甘油）癸二酸酯丙烯酰胺（PGSA）单独组成的导电双相复合材料，和掺杂聚（吡咯）（PPy），被制备成具有高和低导电性的交替段。导电性测量表明，0.05% PPy 添加到 PSA 中可达到 1.25×10 S/cm 的最佳值，用于随后的电刺激。掺杂和未掺杂 PGSA 的 PPy 拉伸测试和降解表明，PGSA 的丙烯酰化率为 35-40% 与神经机械性能相匹配。当在复合材料上培养成纤维细胞和神经元细胞时，两者都生长良好。用 3V、20Hz 刺激的双相 PGSA/PPy 片上接种神经元细胞，与未刺激的复合材料相比，在刺激 1 天时细胞增加了 5 倍，在刺激 3 天时细胞增加了 10 倍。适合植入大鼠坐骨神经模型进行神经修复的重复高和低导电性材料制成的管状导管在体内进行了评估，优于硅胶导管。这些结果表明，能够维持机械性能而不会引起压迫性损伤，同时产生重复电场的双相导电导管是加速以前无法治疗的患者周围神经修复的有前途的工具。
