Influence of impregnation of samarium oxide into xanthan gum hydrogels on antimicrobial, antioxidant, swelling, drug delivery and biomedical properties.

Recently extensive efforts have been made to develop the bioactive materials to induce antimicrobial, antioxidant and biocompatible properties. Keeping in view the biological activity, chemical stability and tunable biocompatibility of samarium oxide (Sm2O3), herein impregnation of Sm2O3 has been carried out to induce antimicrobial properties into hydrogels and to evaluate effect of Sm2O3 immobilization on physicochemical, drug delivery (DD) and biomedical properties. The Sm2O3 impregnated hydrogels were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and field emission scanning electron microscopy (FESEM) analysis. The study also elucidated the profound impact of Sm2O3 integration on the structural parameters, mechanical strength and its correlation with biomedical aspects of the polysaccharide network. The impregnation of Sm2O3 (3.83 × 10-2 mol/L) into xanthan gum (XG) hydrogel was carried out during synthesis of hydrogels by graft copolymerization method. The optimized reaction parameters used for synthesis of hydrogels were: [XG] = 5% (w/v), acrylic acid [AAc] = 4.37 × 10-1 mol/L, vinyl sulphonic acid [VSA] = 5.65 × 10-2 mol/L, N,N'-methylene bisacrylamide [NNMBA] = (19.4 × 10-3 mol/L) and ammonium persulphate [APS] = 2.19 × 10-2 mol/L. The impregnation of Sm2O3 was evidenced by significant suppression of equilibrium swelling ratio and a reduction in porosity from 42.44 ± 2.00% (native matrix) to 23.20 ± 1.79% for the Sm2O3 embedded composite hydrogels. Azteronam loaded hydrogel composites exhibited antibacterial efficacy against both gram positive (S. aureus, ZOI = 16 mm) and gram negative (P. aeruginosa, and E. coli, ZOI = 22 mm for both) bacterial strains. The release profile of azteronam from hydrogels, with and without Sm2O3 impregnation, followed non-Fickian diffusion mechanism and was best described by first order kinetic model. These findings underscore the potential of Sm2O3 containing hydrogels for drug delivery applications.