Rifampicin adsorption and release study using Santa Barbara amorphous-16 modified Al (SBA-16-Al) for a drug delivery system

Abstract

In this study, the surface modification of Santa Barbara Amorphous-16 (SBA-16) with aluminum (SBA-16-Al) was carried out as a rifampicin matrix for the treatment of tuberculosis. Surface modification of SBA-16 was achieved using the direct-synthesis grafting method. Then, the adsorption and release properties of rifampicin from the SBA-16-Al matrix have been studied in batches. In addition, the SBA-16-Al has been characterized using Fourier-Transform Infrared Spectroscopy (FTIR), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), and Surface Area Analysis (SAA) Brunaur, Emmett and Teller (SAA-BET). The results show that the mesoporous material, the SBA-16-Al has a specific surface area of 843.5 m² g⁻¹ and 624.3 m² g⁻¹ for SBA-16, nanometer-sized pore diameters, and an amorphous crystal lattice. The FTIR spectra showed the Al–O bond at 802 cm⁻¹ which indicates the Al group has been successfully added into SBA-16. The adsorption isotherm of rifampicin in SBA-16-Al follows the Freundlich model which illustrates the adsorption is heterogeneous and forms a multilayer. The adsorption of rifampicin is chemisorption which occurs non-spontaneously and is quite stable. The release kinetics of rifampicin in the drug delivery system followed the Higuchi model with k₁ 0.5472 mg 0.5/hour pH 1.5 and k₂ mg 0.5/hour pH 6.5.