Green fabrication and characterization of debranched starch nanoparticles via ultrasonication combined with recrystallization

With recent advances in nanotechnology, debranched starch nanoparticle (DBS-NP) materials have attracted considerable interest from the fields of functional food, biomedicine, and material science, thanks to their small size, biodegradability, biocompatibility, sustainability, and non-hazardous effects on health and the environment. In this study, DBS-NP was fabricated using an eco-friendly method involving ultrasonication combined with recrystallization. The effects of ultrasonication and recrystallization times on the morphology, particle size, and crystal structure of the DBS-NPs were systematically investigated. Compared with the DBS-NPs prepared using ultrasonication treatment only, the DBS-NPs formed using ultrasonication combined with recrystallization were uniform in size and well distributed in aqueous solution. Moreover, the maximum encapsulation efficiency and loading capacity of the epigallocatechin gallate (EGCG) in the DBS-NPs with ultrasonication treatment reached 88.35% and 22.75%, respectively. The particle sizes of the EGCG@DBS-NP were more stable at a neutral pH (7.4) than at an acidic pH (2.1). The EGCG in the EGCG@DBS-NP displayed excellent radical scavenging activity and antibacterial effects, and cell assays demonstrated that the EGCG@DBS-NP was non-toxic and highly biocompatible.