Functionalization of almond gum through covalent and non-covalent interactions for biomedical applications

The versatile properties of carbohydrate polymers make them a relevant, promising precursor to design innovative materials for use in biomedical applications. Recent research mainly focuses on the development of the polysaccharide based functional materials. Hydrogel derived materials are a source of great motivation for the development of drug delivery (DD) carriers with inherent therapeutic potential. Herein, almond gum-based hydrogels were synthesized for the delivery of the anticancer drug methotrexate after impregnation to improve the DD profile. Hydrogels were characterized by FESEM, EDS, AFM, ¹³C NMR, FTIR, TGA, DSC, XRD, mechanical strength & biomedical assay. The optimized network hydrogel exhibited a mesh size of 19.764 mm and a cross-linking density of 5.002 × 10^-5 mol/cm³ of the hydrogels. Morphological features revealed irregular, uneven internal morphology of hydrogels in FE-SEM. The inclusion of sulphated and amide polymers in hydrogels was found in elemental composition (C = 60.72 %, O = 29.79 %, N = 6.63 % and S = 2.86 %) of hydrogels inferred from EDS. Spectroscopic characterization by FT-IR and ¹³C NMR confirmed the inclusion of PVP and PVSA through grafting reaction. The crosslinked product formed was found thermally stable and amorphous in nature through TGA and XRD analysis. The sustained release was found through supramolecular interactions and release complied a non-Fickian mechanism for drug diffusion (n = 0.73) and the release profile was best described by the Hixson-Crowell kinetic model in colonic pH. The hydrogels were mucoadhesive in nature and required 144 ± 10.54 mN force for the separation of hydrogels from the mucosal surface during the adhesion test. Hydrogel illustrated antioxidant activity (32.68 ± 0.83 μg GAE) during their radical scavenging test by FC reagent assay. Drug encapsulated hydrogels demonstrated antimicrobial efficacy against microbes. The results of physico-chemical and biomedical properties of hydrogels suggested their suitability for biomedical uses.