Preparation of debranched starch nanoparticles by ionic gelation for encapsulation of epigallocatechin gallate.

Starch nanoparticles are promising candidates for the delivery of active compounds or drugs. The purpose of this study was to prepare nanoparticles from debranched starch using an ionic gelation method. Negatively charged carboxymethyl debranched starch (CMDBS) was obtained by modification of debranched starch (DBS). The zeta potential value of CMDBS with a degree of substitution of 0.81 was approximately -26 mV. The starch nanoparticles formed from 2 mg mL-1 CMDBS and cationized DBS (CDBS) had particle sizes of 50 to 100 nm, as determined by transmission electron spectroscopy, and most nanoparticles were spherical in shape. Measurements with a quartz crystal microbalance with dissipation monitoring confirmed a successful adsorption interaction between the negatively charged CMDBS and positively charged CDBS. Epigallocatechin gallate (EGCG) was successfully incorporated into the nanoparticles with the highest encapsulation efficiency of 84.4%, and the resulting nanoparticles showed controlled release of EGCG into simulated gastric and intestinal fluids.