Influence of functionalized mesoporous silica in controlling azathioprine drug release and cytotoxicity properties

Abstract

The present study is focused on functionalisation of mesoporous silica (or SBA-15) to control azathioprine drug release rate and its toxic effect. The mesoporous silica was functionalised by (γ-chloropropyl)triethoxysilicane and (3-aminopropyl)triethoxysilane (APTES) via hydrothermal process. The azathioprine was loaded into SBA-15 via post impregnation method. Azathioprine-loaded pristine and functionalised SBA-15 samples were characterised using UV–visible spectrophotometry and thermogravimetric analysis to measure the drug loading efficiency. The samples were also characterised by small and wide-angle powder X-ray diffraction, scanning electron microscope, transmission electron microscope, infrared spectroscopy and nitrogen adsorption/desorption analysis to study the structure, morphology, functionalisation and drug loading in detail. The maximum drug loading efficiency of 65(±1)% was achieved. In vitro azathioprine release profiles were studied in phosphate buffered saline (pH 7.4) and results suggested that the drug release amount could be controlled by functionalisation of carrier matrix SBA-15. Azathioprine-loaded APTES-functionalised material revealed lowest release amount of ~64.5% in 60 h. The toxicity of azathioprine was significantly reduced by loading the drug into the mesoporous pristine and functionalised silica. The controlled azathioprine release reduced its repeated administration and can reduce its toxicity and side effects. These outcomes recommend that the functionalised SBA-15 is an advantageous drug carrier for achieving extended release time.