Preparation of octenyl succinic anhydride-modified debranched starch vesicles for loading of hydrophilic functional ingredients

Vesicles have been attracting a great deal of interest because of their great potential for health food, medicine, and biotechnology applications. This study aimed to develop a new type of debranched starch (DBS) vesicle for loading and delivering active components. DBS with a low degree of polymerization (6.75) and good water solubility was modified with octenyl succinic anhydride (OSA) to obtain an amphiphilic polymer. Both the Fourier transform infrared spectroscopy and the 1H nuclear magnetic resonance results confirmed the successful synthesis of amphiphilic OSA-DBS polymers. The OSA-DBS spontaneously formed 10–30 nm vesicles in a water system, as measured by transmission electron microscopy. The vesicles were relatively stable at different temperatures, pH values, and ionic strengths. Insulin was used as a hydrophilic functional ingredient model. The insulin-loaded vesicles exhibited a high loading content (∼13.36%). These OSA-DBS vesicles have potential utility as advanced carriers in the health food and biomedical industries.