Optimization of tetracycline hydrochloride adsorption on amino modified SBA-15 using response surface methodology

Several researchers are focused on preparation of mesoporous silica as drug carriers with high loading efficiency to control or sustain the drug release. Carriers with highly loaded drug are utilized to minimize the time of drug intake. In this study, amino modified SBA-15 was synthesized through grafting with amino propyl triethoxy silane and then loaded with tetracycline hydrochloride. The drug loading was optimized by using the response surface method considering various factors including drug to silica ratio, operation time, and temperature. The drug to silica ratio indicated as the most influential factor on the drug loading yield. Further, a quadratic polynomial equation was developed to predict the loading percentage. The experimental results indicated reasonable agreement with the predicted values. The modified and drug loaded mesoporous particles were characterized by FT-IR, SEM, TEM, X-ray diffraction (XRD), elemental analysis and N2 adsorption-desorption. The release profiles of tetracycline-loaded particles were studied in different pH. Also, Higuchi equation was used to analyze the release profile of the drug and to evaluate the kinetic of drug release. The drug release rate followed the conventional Higuchi model that could be controlled by amino-functionalized SBA-15. Further, the drug delivery system based on amino modified SBA-15 exhibits novel features with an appropriate usage as an anti-bacterial drug delivery system with effective management of drug adsorption and release.