National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou 215123, People's Republic of China.
I3Bs Research Institute on Biomaterials, Biodegrabilities, and Biomimetics, Headquarters of the European Institute of Excellence on Tissue Engineering and Regenerative Medicine, University of Minho, Barco 4805017, Portugal.
Int J Biol Macromol. 2023 Jul 1;242(Pt 1):124684. doi: 10.1016/j.ijbiomac.2023.124684. Epub 2023 May 4.
To date, very limited work has been done on convenient and active control of insulin release. Herein, we report an electro-responsive insulin delivery system based on thiolated silk fibroin. The disulfide cross-linking points in TSF were reduced and broken to form sulfhydryl groups under electrification, which led to the increase of microneedle swelling degree and promoted insulin release. After power failure, the sulfhydryl group is oxidised to form disulfide bond crosslinking point again, resulting in the reduction of microneedle swelling degree and thus the reduction of release rate. The insulin loaded in the electro-responsive insulin delivery system showed good reversible electroresponsive release performance. The addition of graphene reduced the microneedle resistance and increased the drug release rate under current conditions. In vivo studies on type 1 diabetic mice show that electro-responsive insulin delivery system effectively controls the blood glucose before and after feeding by switching on and off the power supply, and this blood glucose control can be maintained within the safe range (100-200 mg/dL) for a long time (11h). Such electrically responsive delivery microneedles show potential for integration with glucose signal monitoring and are expected to build closed-loop insulin delivery systems.
迄今为止，人们对胰岛素的方便和主动释放的控制研究非常有限。本文报道了一种基于巯基化丝素蛋白的电响应胰岛素递送系统。在通电时，TSF 中的二硫键交联点被还原和打破形成巯基，这导致微针的溶胀度增加，促进胰岛素释放。断电后，巯基再次被氧化形成二硫键交联点，导致微针溶胀度降低，从而降低释放速率。负载在电响应胰岛素递送系统中的胰岛素表现出良好的可逆电响应释放性能。添加石墨烯可降低在电流条件下微针的阻力并增加药物释放速率。在 1 型糖尿病小鼠的体内研究中，电响应胰岛素递送系统通过打开和关闭电源，有效地控制了进食前后的血糖水平，并且这种血糖控制可以在较长时间（11 小时）内维持在安全范围（100-200mg/dL）内。这种电响应递送微针有望与葡萄糖信号监测集成，并构建闭环胰岛素递送系统。
