Synthesis and Characterization of Mesoporous Silica Nanoparticles Loaded with Repaglinide for Dissolution Enhancement

Abstract

It was evident from the literature that mesoporous silica nanoparticles can be a suitable drug carrier system because of biocompatibility, drug loading capacity; targeting ability and tunable porosity. This investigation was aimed to synthesize mesoporous silica carriers by sol-gel method using tetraethyl orthosilicate as precursor and cetyl trimethyl ammonium bromide and cetylpyrridinium chloride as a pore generating agent. Initially the effect of molar concentrations of cationic surfactants on the pore size of porous nanoparticles was studied followed by loading of repaglinide onto the surface as well as inside the pores of nanoparticles by solvent immersion method. The loaded mesoporous silica nanoparticles were evaluated for % drug loading and in vitro release. Techniques including N2-adsorption-desorption isotherm, x-ray diffractometry, scanning electron microscopy were used for characterization. The drug loading (90.3±0.25 %) was observed highest in case of nanoparticles prepared with and cetyl trimethyl ammonium bromide than that of cetylpyrridinium chloride. The drug release was found 96.5±1.15 % which was more than that of pure drug and marketed formulation. The results revealed drug loading with slight decrease in crystallinity of drug in mesoporous silica nanoparticles. The particles were spherical in shape with smooth surface. In conclusion the mesoporous silica nanoparticles had shown increased dissolution because of increased surface area.