A customized partitioned microneedle array based on functionalized glycol chitosan for prolonged blood glucose regulation and prevention of diabetic neuropathy

Efficient glycemic control serves as the cornerstone of diabetes and its complication treatments, necessitating additional symptomatic medications or nutritional supplements tailored to various complications. However, different diseases and medications require specific treatment regimens and drug delivery methods. For instance, conventional subcutaneous insulin injections suffer from uncontrollable release rates and onset times. This study has developed a segmented microneedle array that integrates two controlled-release mechanisms within a single array. Different drugs are loaded into distinct regions, allowing for modular and simultaneous timed-release therapies. The posterior segment of the microneedle tip releases insulin via a glucose-sensitive mechanism, enabling real-time intelligent glycemic regulation and effective glycemic control for up to 43.7 h, which is nearly 8 times longer than subcutaneous injections. The anterior segment releases vitamin B9 via a sustained-release mechanism, which has potential preventive and reparative effects on diabetic neuropathy, providing a gentler and more sustained nutrient supply. The regionalized design of the microneedles significantly enhances drug delivery efficiency and the intelligent customization of drug release, especially in managing diabetic neuropathy.