Fabrication of SnO2/porous silica/polyethyleneimine nanoparticles for pH-responsive drug delivery

Abstract

To create novel nanocarriers for achieving excellent drug delivery performance, pH-responsive fluorescent porous silica (PS) nanocarriers were developed by encapsulating SnO2 nanoparticles and coating polyethyleneimine (PEI) layer. SnO2/porous silica (SnO2/PS) nanoparticles have an average diameter of 80nm and center-radial large pore channels. The large channels endow them high surface area with a Brunauer-Emmett-Teller (BET) area of 939m(2)g(-1). Aspirin was used as test drug to evaluate the releasing behavior of SnO2/porous silica/polyethyleneimine (SnO2/PS/PEI) nanoparticles. Results indicated that aspirin can be successfully incorporated into the SnO2/PS/PEI nanoparticles and the SnO2/PS/PEI nanoparticles displayed excellent pH-responsive release. The release rate in pH7.4 buffer is higher than that in pH5.5 buffer, which attributed to the PEI structure change in varied pH buffer. In addition, the SnO2/PS/PEI nanoparticles presented novel drug-dependent fluorescence, which could be used to trace the drug release.

Keywords: Drug delivery; Drug-dependent fluorescence; Nanocarriers; SnO(2)/porous silica/polyethyleneimine; pH-responsive.