Preparation and sustained-release performance of nitenpyram@MCM-41 mesoporous silica/HTCC nanoparticles

MCM-41 mesoporous silica was dispersed in nitenpyram aqueous solution. With further sonication, nitenpyram was absorbed and entered into the pores of MCM-41 MSNs. The efficient positively charged polymer (a quaternized chitosan, (N-(2-hydroxyl) propyl-3-trimethylammonium chitosan chloride, HTCC) coating was realized by the electrostatic interaction and hydrogen bonding between the silicon-hydroxyl groups on the silica nanoparticles and the HTCC. For the shell of HTCC, nitenpyram was encapsulated inside the pores of MSNs. So that a slow and sustained release was realized. The structures, morphologies and Zeta potential, etc. of MCM-41 MSNs and nitenpyram@MCM-41/HTCC nanoparticles were systematically studied using scanning electron microscopy (SEM), N₂ adsorption-desorption, transmission electron microscopy (TEM), X-ray diffraction assay (XRD), dynamic light scattering particle size analysis(DLS) and fourier transform infrared spectroscopy (FTIR). The adsorption capacity and release property of nitenpyram@MCM-41/HTCC nanoparticles were also evaluated. The results showed that, HTCC, successfully wrapped on the surface of nitenpyram@MCM-41 nanoparticles, was served as the shell of nitenpyram@MCM-41/HTCC nanoparticles. The loading content was 2.8%, and the novel nitenpyram@MCM-41/HTCC nanoparticles have good sustained-release performance.