Dual-responsive Controlled Drug Delivery Systems With High Drug Loading Capacity Based On Hollow Mesoporous Organosilica Nanoparticles

Amongst the various drug nanocarriers,hollow mesoporous organosilica nanoparticles?HMONs?have more advantages,such as,large specific surface area,high drug loading capacity,high biocompatibility and chemical stability,and unique stimuli-responsiveness.Herein,we have developed a novel dual-responsive DDS?DOX@HMONs-CD?with high drug loading capacity based on HMONs,For the first time,The DOX@HMONs-CD that integrate stimuli-responsiveness of the pore channels and the framework for controlled release of drugs.The drug delivery system provide significant guidance for the design of new drug controlled release system.Monodispersed SiO₂ nanoparticles were initially synthesized according to the typical Stober method,we synthesized core/shell structured SiO₂@MONs with thioether groups within the framework by a typical SiO₂ templating approach,SiO₂@MONs were further functionalized with N-phenylaminopropyltrimethoxysilane?PhAPTMS?,after the solid silica core was completely etched in HF solution and the CTAB mesoporous template was removed by HCl/ethanol solvent extraction to form the functionalized hollow mesoporous organosilica nanoparticles?HMONs-NH2?.The transmission electron microscopy?TEM?shows image of nanoparticles with highly uniform and monodispersed Spheres.The information of MAS NMR spectra,the thermal gravimetric analysis?TGA?and raman spectrum indicates the preparation core/shell nanostructures and the incorporation of PhAPTMS on the surface of organosilica framework successfully.The analysis of N2 adsorption desorption isotherm shows the nanoparticles have large surface area?989 m2/g?.We preparated dual-responsive Controlled drug delivery systems?DDS?based on HMONs,PhAPTMS used as the thread molecule,a-CD was chosen as the capping molecule.The DOX@HMONs-CD show high loading capacity?1060 mg/g?for anticancer drug?doxorubicin?.The cumulative release could be tuned by varying the pH or the concentration of dithiothreitol?DTT?,and the system exhibited an obvious enhanced release capacity in the combination of two stimuli.