Microneedles with Two-Stage Glucose-Sensitive Controlled Release for Long-Term Insulin Delivery

Diabetes patients cannot complete effective blood glucose regulation due to their impaired pancreatic function. At present, subcutaneous insulin injection is the only treatment for patients with type 1 and severe type 2 diabetes. However, long-term subcutaneous injection will cause patients with intense physical pain and lasting psychological burden. In addition, subcutaneous injection will lead to hypoglycemia risk to a large extent because of the uncontrollable release of insulin. In this work, we developed a glucose sensitive microneedle patch based on phenylboronic acid (PBA)modified chitosan (CS) particles and poly(vinyl alcohol) (PVA)/ poly(vinylpyrrolidone) (PVP) hydrogel for the efficient delivery of insulin. Meanwhile, through the double glucose-sensitive response process of CS-PBA particle and external hydrogel, the sudden release of insulin was well restrained, and a more persistent blood glucose control was achieved. Finally, the painless, minimally invasive, and efficient treatment effect of the glucose-sensitive microneedle patch indicated its great advantages as a new generation of injection therapy.

Automated summary

Diabetes patients with impaired pancreatic function cannot effectively regulate blood glucose and currently, subcutaneous insulin injection is the only treatment option. However, this method causes intense physical pain and psychological burden. Additionally, the uncontrollable release of insulin in subcutaneous injection leads to a high risk of hypoglycemia. In this study, a glucose-sensitive microneedle patch was developed using modified chitosan particles and hydrogel, which effectively delivered insulin and achieved persistent blood glucose control. The painless and minimally invasive nature of this patch indicates its advantages as a new generation of injection therapy.