الفهرس | Only 14 pages are availabe for public view |
Abstract In the present study, xanthan gum (XG) structure was modified with antibacterial and thermally stable poly (N-vinyl imidazole) (PVI), through three different techniques (XG / PVI blends, XG-g-PVI copolymers and crosslinked XG-g-PVI hydrogels) to overcome XG bacterial contamination and can to be used as an efficient adsorbent for crystal violet (CV) dye and as a pH-sensitive carrier for protein delivery. All the prepared samples were characterized via different analysis tools such as FTIR, FE-SEM, XRD, TGA and EDX.Antibacterial activity of tested samples was done against two pathogenic microorganisms (S. aureus as Gram-positive bacterium and E. coli as Gram-negative bacterium) in presence of Amoxicillin as reference drug. The results showed the increase in the antibacterial activity occurs with the increase in PVI content and crosslinked XGg- PVI hydrogels had the most antibacterial activity. In addition, results of the adsorption of CV dye showed that XG / PVI blends and crosslinked XG-g-PVI hydrogels had the highest adsorption capacity for removal of CV dye. The maximum adsorption capacity (Qmax) was found to be 453 mgg-1 for XG / PVI blend and 625 mgg-1 for crosslinked XGg- PVI hydrogel. Also, the desorption study showed that XG / PVI blend and crosslinked XG-g-PVI hydrogel have an efficient regeneration (recycling) ability for removing CV dye molecules from an aqueous solution. Furthermore, the swelling ability of XG / PVI blends and crosslinked grafted XG hydrogels was studied in two different pHs media (pH 7.4 and pH 2). The obtained results revealed that the swelling rate of tested samples increased with increasing time intervals. However, the percentage of water uptake of blends in phosphate buffer saline (PBS) was higher than that in acidic buffer solution.In addition |