Swelling behavior and mechanical strength of crosslinked dextran hydrogel

Abstract

Dextran as a candidate material for colon-specific drug delivery has been studied. Crosslinked dextran hydrogels were prepared by mixing dextran, MgCl 2 , glutaraldehyde (GA) and polyethyleneglycol (PEG 400) in water. The dextran hydrogels were characterized by measuring equilibrium swelling ratios and mechanical strengths. Response surface methodology (Central Composite Design) was used to evaluate the swelling behaviors and mechanical strengths as functions of concentrations of MgCl 2 , GA, and PEG 400, which was found to be useful for the evaluation. It showed that the swelling behavior and mechanical strengths were influenced significantly by PEG 400 and MgCl 2 concentrations.

Low viscosity hydrogel of guar gum: Preparation and physicochemical characterization

“…It has been used as a cross-linking agent for the preparation of dextran hydrogels [15] and for several drug delivery systems, such as polyampholyte hydrogels based on carboxymethyl chitosans [12], fibroin blends films [16] and gelatin hydrogel incorporating cisplatin [17]. It has been utilized for preparation of bioprosthesis, such as heart valves and elastic cartilages [18].…”

Preparation and characterization of spray-dried gelatin microspheres encapsulating ganciclovir

“…At higher concentration, however, aldehyde groups form covalent imine bonds with the amino groups of gelatin, due to resonance established with adjacent double ethylenic bonds via a Schiff reaction, obstructing the entry of solvent. 24,25 In addition, the cross-linked microspheres showed a faster initial swelling rate, followed by much slower swelling. This was attributed to a high hydrodynamic free volume that accommodated more solvent pockets during the initial period of swelling.…”

Preparation and characterization of ethylcellulose-based microcapsules for sustaining release of a model fragrance

“…BTCA was used primarily for crosslinking. Glutaraldehyde, a frequently used crosslinking agent 13,14 was also applied in some preliminary experiments, though the capsules prepared possessed unpleasant smell and glutaraldehyde is toxic, thus, it was not applicable for this purpose. Badulescu et al 7 proved using Fourier transform infrared analysis that EC-vanillin capsules can be efficiently bound to textile covalently, as ester bonds were formed between hydroxyl groups of EC and carboxyl groups of BTCA.…”