Biofunctional mesoporous silica nanoparticles for magnetically oriented target and pH-responsive controlled release of ibuprofen

A dual-stimuli-responsive drug delivery system, with magnetic oriented target and pH-sensitive characters, has been prepared. The materials show highly ordered mesostructure, high pore volume, regular nanoparticle morphology (500 nm), and superior magnetic property. The materials were characterized by XRD, TEM, BET, FTIR and vibrating sample magnetometer technique (VSM). The pH-sensitive magnetic mesoporous silica nanoparticles (MMSNs) was served as a drug carrier, with ibuprofen (IBU) being the model drug. The release kinetics in simulated gastric fluid (SGF, pH 1.2) and in simulated proximal intestine fluid (SIF, pH 7.4) were studied respectively. It is found that the drug release increased rapidly when the release medium was changed from SGF to SIF. These dual-functional drug delivery systems with magnetically oriented target and pH-responsive performances may predictably have application in biomedical field. (C) 2012 Elsevier B.V. All rights reserved.