Preparation and characterization of cationic hyperbranched maltodextrins as potential carrier for siRNA encapsulation

The present study sought to investigate the physicochemical properties of cationic branched maltodextrins with similar degrees of substitution but different degrees of branching and their siRNA delivery capacity. The results showed that the ratio of α-1,6 glycosidic bonds was significantly increased in the sample treated with dual enzymes. The structural characterization results showed that abundant short chains reassembled by 1,4-α-glucan branching enzyme (GBEs) hydrolysis formed hyperbranched short clustered structure. The absorption peaks that appeared in the FT-IR spectrum confirmed the occurrence of quaternization. The complexes formed by self-assembly of cationic maltodextrins and siRNA were verified by the gel retardation assay and atomic force microscopy, demonstrating a uniform spherical structure with a size close to 300-350 nm. Meanwhile, cationic branched maltodextrins could effectively reduce the change of secondary structure of siRNA. Overall, the results suggested that branched maltodextrins with a cationic surface had significant potential as siRNA carriers.