Formulation and Evaluation of Silymarin-Loaded Chitosan-Montmorilloite Microbeads for the Potential Treatment of Gastric Ulcers

Abstract

Silymarin-loaded mucoadhesive microbeads of Chitosan-MMT were developed using the ionotropic gelation technique. Characterization of the microbeads was performed by DSC, XRD, SEM, and FTIR techniques. In vitro mucoadhesion and drug release studies; gastroprotective studies including the measurement of ulcerative index; the determination of gastric wall mucus; and the determination of percentage protection, biochemical, and histopathological studies were also performed. Microbeads batches were evaluated for particle size (120⁻140 µm), actual drug content, (49.36⁻58.18%) and entrapment efficiency (72.52⁻92.39%).Biochemical estimation of myeloperoxidase was found to be 0.10⁻0.75 µmoles/g/tissue. Significant reduction in the ulcerative index showed the gastroprotective effect of the formulation. Silymarin-loaded beads of Chitosan-MMT were found to exhibit good mucoadhesion and efficient release of the drug, and were found to be a promising drug carrier system for the treatment of gastric ulcers.

Keywords: Microbeads; chitosan; gastric ulcers; montmorillonite; silymarin.

Figure 1

Average diameter of Silymarin-loaded Chitosan-MMT microbeads of different batches.

Figure 2

Layout representing the FTIR spectra of CMMTB51, Silymarin, MMT, and Chitosan.

Figure 3

DSC thermogram of (a) drug, (b) CMMTB51, (c) MMT, and (d) Chitosan.

Figure 4

SEM images of formulated beads at different magnification value (a) at 95×, (b) 45×, (c) 1000×, and (d) 3000×.

Figure 5

X-ray Diffraction pattern of (a) Silymarin- and (b) Silymarin-loaded Chitosan-MMT beads.

Figure 6

In vitro release profile of Silymarin from different batches of microbeads.