基于丝素/聚丙烯酸水凝胶的柔性释药生物电极

Flexible Drug Release Bioelectrode Based on Silk Fibroin/Polyacrylic Acid Hydrogel

采用原位自由基聚合法在丝素溶液中聚合丙烯酸,制备得到丝素/聚丙烯酸水凝胶。在水凝胶上加载正电荷药物盐酸万古霉素,并将水凝胶与柔性导电基底复合,得到柔性凝胶释药生物电极。对该凝胶的电极力学、黏附、药物释放等性能进行表征,发现丝素与丙烯酸质量比为1∶10的水凝胶具有8.5 kPa的杨氏模量和143%的断裂伸长率,同时黏附强度也达到了56 kPa,证实其在拉伸和黏附性能方面具有良好的平衡性。凝胶内部介观网络结构提供了加载正电药物的空间和位点,在48 h后凝胶可达到药物加载的饱和点。凝胶电极可在0.5 V的电压下实现10 h持续电控释放。本研究为柔性电控释药电极的发展奠定了基础,有望应用在促进伤口愈合等领域。

Silk fibroin/polyacrylic acid hydrogel was prepared by in-situ radical polymerization of acrylic acid in silk fibroin solution.Positive charge drug vancomycin hydrochloride was loaded on the hydrogel,and a flexible gel drug release bioelectrode was obtained by combining the hydrogel with the flexible conductive substrate.The mechanical,adhesive and drug release properties of the gel electrode were characterized.The results show that the hydrogel with a 1∶10 mass ratio of silk fibroin and acrylic acid has a Young's modulus of 8.5 kPa and an elongation at break of 143%,as well as an adhesion strength of 56 kPa,demonstrating a good balance in tensile and adhesive properties.The mesoscopic network in the hydrogel provides space and sites for loading positive drugs,the hydrogel reaches to the saturation point of drug loading after 48 h.The gel electrode keeps electric control release of 10 hours under the voltage of 0.5 V.This study lays a foundation for the development of flexible electrically controlled drug release electrodes and is expected to be applied in medical fields such as promoting wound healing.