Preparation and characterization of type Ⅲ sodium-phosphate cotransporter siRNA-loaded chitosan nanoparticles / 第二军医大学学报

ABSTRACT

Objective:To prepare type Ⅲ sodium-phosphate cotransporter(NaPi-Ⅲ) siRNA-loaded chitosan microspheres and to evaluate their physico-chemical properties and siRNA release in vitro.Methods: NaPi-Ⅲ siRNA was loaded into chitosan microspheres by using the complex coacervation method.The structure of the nanoparticles was observed under scanning electron microscope and their diameter distribution was measured by a laser grain analyzer.RNase assay was used to detect the efficacy of anoparticles in prevention of siRNA from degradation.Ultraviolet spectrophotometry and HPLC technique were used to determine the entrapment efficiency,loading capacity,and siRNA releasing rate in vitro.Results: The chitosan nanoparticles loaded with NaPi-Ⅲ siRNA were successfully prepared.The nanoparticles were spherical in shape and were well distributed,with an average diameter of 173 nm.After RNase treatment,D_(260) rose more slowly in chitosan nanoparticles-based siRNA suspension than in simple NaPi-Ⅲ siRNA solution(P