The development and characterization of starch microspheres prepared by a sonochemical method for the potential drug delivery of insulin

This study deals with the production of starch microspheres containing insulin using the sonochemical technique. The structure and properties of the final product were studied using SEM, FTIR and XRD. A microsphere size of 600nm and the size istribution of the starch microspheres with encapsulated insulin were determined. A spectrophotometric analytical procedure was selected to evaluate the amount of loaded insulin in the starch microspheres and to perform the release studies. The product is organized in a double-layer structure (insulin layer covered by starch layer), and this composite may provide a new system for the administration of protein drugs. The microspherilization process involves the degradation of the starch to the smaller fragments due to the application of high-intensity ultrasound, and the organization of these fragments in a microsphere structure using the same type of bonds as in regular starch.