A novel controlled release implant of insulin based on Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) polymer prepared by extrusion process

INTRODUCTION: Developing and designing an implant with a controlled release of active protein drugs has always been a challenge. In order to optimize and control the release of insulin in this project, the drug complexing mechanism was used by dextran sulfate sodium and PHBV (Poly (3-hydroxybutyrate-co-3-hydroxyvalerate)) polymer.
METHODS: For this purpose, initially, the efficacy of drug binding was evaluated under different molecular ratios of Dextran sulfate sodium, and then a TGA test was done to check the stability of the drug complex in extrusion. In the final stage, rod shape implants of complexed insulin were prepared by an extrusion process, and the drug release was evaluated within 32 days. The kinetics of drug release were evaluated based on mathematical models.
RESULTS: The results showed an increase in insulin binding efficiency percent, up to a ratio of 2.6. The drug release of the implant containing complexed insulin was in a completely controlled form. The drug release followed a zero order release model. Interestingly, the complex form of drug showed a temperature resistance of 160 ˚C for ten minutes.
DISCUSSION AND CONCLUSION: In this study, for the first time, a controlled release implant of insulin has been developed based on a PHBV polymer. In this method, the extrusion process has been used, which provides the possibility of preparing implants on an industrial scale in the future, and also, their development appears to be a promising treatment for diabetic patients and lead to the elimination of frequent drug injections and then more adherence of the patients to the continuation of the treatment process.