Enzyme‐based hydrogels containing dextran as drug delivery carriers: Preparation, characterization, and protein release

Abstract

Novel enzyme-based hydrogels for drug delivery were prepared by combining dextran with 5,5 0 -azodisalicylic acid using isophorone diisocyanate as the crosslinking agent. The structure of the resultant dextran/5,5 0 -azodisalicylic acid hydrogels was determined by infrared spectra, and the properties of the hydrogels were characterized by swelling measurements and scanning electron microscopy analysis. It was found that changing the concentration of 5,5 0 -azodisalicylic acid affected the crosslinking density of the hydrogels and resulted in significant differences in the water swelling property and degradability of the hydrogels. Compared with their degradability, the degradation of the hydrogels seemed to be more pronounced by azoreductase in cecum content medium than that by hydrolysis in phosphate buffer solution (PBS). Also, the release rate of the protein in cecum content medium was faster than that in PBS. Attributing to the results of the resultant hydrogels described earlier, it could be concluded that dextran/ 5,5 0 -azodisalicylic acid hydrogels could be used as a potential enzyme-based carrier for colon-specific drug delivery.

Temperature responsive hydrogel with reactive nanoparticles

“…1–3 Responsive hydrogels can undergo a swelling transition in response to environmental stimuli, such as the changes in temperature, light, pH, etc. 4–7 Because of this unique feature, responsive hydrogels have received extensive attention in the fields of drug delivery, 8 bioseparation, 9 sensors, and optical transduction of chemical signals.…”

Swelling behavior of novel protein‐based superabsorbent nanocomposite

“…Synthesis and swelling behavior of hydrogels containing 2‐acrylamido‐2‐methylpropane sulfonic acid (AMPS) have been investigated 21–25. Also, because of their biocompatibility, biodegradability, and nontoxicity, polysaccharides26–28 and proteins29–31 have been used to synthesize biopolymer‐based superabsorbents or nanocomposite hydrogels. In the present study, we attempted to synthesize a novel collagen‐based superabsorbent nanocomposite using the acrylamide (AAm) and AMPS monomers a well as Na‐MMt clay, and investigated the effect of reaction variables on the equilibrium swelling (ES) capacity.…”