Development of polymeric microbeads-intercalated with montmorillonite nanoclay and silver nanoparticles for controlled release of levofloxacin, an antibacterial drug

Abstract

Controlled release drug carriers have gained significant interest in recent years due to their potential to produce greater therapeutic success. To address this need, the study presents the fabrication of sodium alginate/poly(vinylpyrrolidone-co-vinyl acetate) microbeads intercalated with montmorillonite (MMT) clay and silver nanoparticles for the controlled release of levofloxacin by a simple ionotropic gelation technique. The prepared beads were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (X-RD), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) etc. The antibacterial activities of the synthesized microbeads were tested against Escherichia coli and Bacillus cereus by the agar disc diffusion method. The developed microbeads could significantly inhibit bacterial development. In vitro release studies and swelling studies were carried out at pH 7.4 simulated intestinal fluid and pH 1.2 simulated gastric fluid at 25 oC and 37 oC. The MMT-containing microbeads showed higher encapsulation efficiency and controlled drug release than other formulations. The results obtained from the swelling and in vitro release studies revealed that pH had influenced the drug release of developed microbeads and that they are suitable for intestinal drug delivery. The in vitro release kinetics was assessed by fitting the release data into the Korsmeyer- Peppas equation and finding that the release mechanism follows the Fickian diffusion process.