Hydrogel membranes based on gum tragacanth with tunable structures and properties. II. Comprehensive characterization of the swelling behavior

Abstract

Hydrogel membranes based on gum tragacanth (GT), with a wide range of crosslinking densities (0.83-23.87 Â 10 À6 mol/cm 3 ) and swelling capacities (120-1580 g/g), were prepared with the aid of heat alone and four crosslinking reagents according to a procedure reported in our previous article. In this article, we report on the comprehensive evaluation of the swelling behavior of the prepared hydrogel membranes. These include the swelling kinetics, swelling behavior in terms of the pH and ionic strength of the swelling media, water absorbency under load (AUL), swelling as a function of sample size, deswelling behavior, and successive swelling and deswelling cycles. The swelling kinetics of the hydrogel membranes with higher crosslinking densities and lower swelling equilibria were closer to those of the case II transport mechanism; this is desirable in the field of drug-delivery systems (DDSs). Furthermore, higher crosslinking densities, and hence stronger structures, of the membranes led to higher AUL values and more stable performances in the successive swelling and deswelling cycles. Moreover, because of the anionic nature of the gum, the prepared GT hydrogels showed pH-and ionic-strengthdependent swelling behavior. All of these results reveal that GT could be a promising material for the preparation of hydrogel membranes for applications in the fields of DDS, tissue engineering, and the separation of small molecules.

Synthesis and properties of a superabsorbent from an ultraviolet‐irradiated waste nameko mushroom substrate and poly(acrylic acid)

“…As shown in Table , the water absorbency was quite low at a neutralization degree of 65% and higher at a neutralization degree of 70%; this was caused by the increase in the ionic dissociation of the carboxylic acid groups . The maximum absorbency (1701 g/g in distilled water and 388 g/g in 0.9 wt % NaCl solution) were obtained when the neutralization degree of AA was 85%.…”

Tragacanth gum as a natural polymeric wall for producing antimicrobial nanocapsules loaded with plant extract

“…The physical, chemical and biological properties of TG including structure, thermal behavior, emulsifying, viscosity, acidity, stability, and also rheological, antibacterial, biocompatibility and biodegradability have been reported by various researchers [2,4,6,10,12,[18][19][20][21]. In recent years, several works are reported on the application of TG in the wound and burn dressing [22], synthesis of silver nanoparticles [2], hydrogel membranes [20], superabsorbent hydrogel [3,23] matrix of verapamil hydrochloride tablets [24], matrix for cell immobilization [10] and drug encapsulation [5,25,26].…”

Synthesis and Characterization of an Enzyme Mediated in situ Forming Hydrogel Based on Gum Tragacanth for Biomedical Applications

“…In the pharmaceutical industry, it is used as a suspending agent in oil-in-water emulsions, jellies and toothpastes, as a stabilizer in dermatological creams and lotions as well as a binding agent in the production of drug tablets (31). Since the past decade, this gum has been investigated as a retarding agent for sustained release of drugs (38) and membranes with possible application in drug delivery systems (39,40). Recently, Fattahi et al (41) showed that physically cross-linked ferric-tragacanth gels exhibit better cell adhesion properties compared to physically cross-linked ferric-alginate gels.…”