940-P: Porous Insulin Microneedles for Diabetes Treatment

Introduction and Objective: Patients with type 1 and type 2 diabetes are subjected to insulin injection therapies. Repeated subcutaneous insulin administrations leads to physiological and psychological issues, such as low adherence, infections, subcutaneous nodules, scarring, and so on. Insulin microneedles enables minimally invasive delivery of insulin, reducing adverse effects of insulin therapy in patients. Herein, we designed a porous insulin microneedle that can release insulin in a controlled manner for diabetes treatment. Methods: Porous microneedles were constructed by gelatin methacrylamide loaded with insulin. We characterized the porous insulin microneedles via optical microscopy and scanning electron microscopy. Biocompatibility was evaluated by utilizing CCK8 assays. To observe penetration effects, agarose hydrogel was used for simulating human skin. The release of insulin from the microneedles was investigated by labeling insulin with FITC. Diabetic mouse models were established and treated with porous insulin microneedles, followed by continuous observation of blood glucose levels. Results: The porous microneedles were demonstrated homogeneous microneedle arrays under microscopy. Transversal section of the microneedles had porous structure, capable of loading macromolecules including insulin. It was shown good biocompatibility when culturing with cells. As minimally invasive patches, the fabricated porous insulin microneedles can penetrate through the skin model, which released insulin into the subcutaneous spaces rapidly. Diabetic mouse models were successfully established with high blood glucose levels. Treated with the porous insulin microneedles, the hyperglycemia was ameliorated in diabetic mice. Conclusion: The resultant porous insulin microneedles can delivery insulin efficiently in a minimally invasive manner, reducing high blood glucose levels of diabetic mice. It is innovative for diabetes treatment, drug delivery, and smart medicine. Disclosure J. Li: None. Z. Huan: None. L. Li: None. Funding National Natural Science Foundation Major International (Regional) Joint Research Program (82320108003); National Natural Science Foundation (82170845, 82000740, 81970717); Key Research & Developement Program (No.BE2022853); Medical Key Discipline (ZDXK202203) of Jiangsu Province; SEU Innovation Capability Enhancement Plan for Doctoral Students (CXJH_SEU 24223)