Present review article aims to explain use of injectable hydrogels and microspheres derived from natural polysaccharides as drug delivery systems and cell scaffolds. Polysaccharides isolated from natural sources are proved much better than synthetic polymers for making single and composite hydrogels. This paper emphasizes recent developments occurred in use of amphiphilic polysaccharides for bi...

Thermo-sensitive hydrogels were prepared by graft copolymerization of Polyvenylalcohol and chitosan with N-Isopropylacrylamide via gamma radiation. Characterization of hydrogels such as DSC analysis and swelling and solubility tests in different ratios were investigated. DSC and solubility analysis showed chitosan and PVA and NIPAAm monomer were grafted via gamma radiation successfully. Results...

The present review aims to give a closer look of hydrogels based on chitosan and poly (vinyl alcohol) and to discuss their potential biomedical applications in drug delivery system. Various investigations based on chitosan/poly (vinyl alcohol) carried out recently by researchers have been reported in this review. Moreover different chemical and physical crosslinking methods used for hydrogels f...

The current paper focuses on the preparation and some characteristics of viscoelastic hydrogels, ViscoGelsTM, made from chitosans having a random acylation pattern. Three different chitosan batches with a high fraction of acetylation were selected based on their Mw, and the impact of degree of cross-linking on these chitosan samples has been studied with respect to the properties of the final h...

Chitosan is a natural polycationic linear polysaccharide derived from chitin. The low solubility of chitosan in neutral and alkaline solution limits its application. Nevertheless, chemical modification into composites or hydrogels brings to it new functional properties for different applications. Chitosans are recognized as versatile biomaterials because of their non-toxicity, low allergenicity...

The development of hydrogels based on natural polysaccharides was investigated by preparing mixtures of policaju/chitosan at weight ratios of 1:4 and 2:3. Utilizing dynamic light scattering (DLS) techniques for these mixtures, an increase on the hydrodynamic particle radius was observed varying their pH from 3.0 to 12.0. Furthermore, a reduction of ζ-potential was also observed for the same pH ...

Recently, the potential application of deferoxamine (DFO) in several iron dysregulation diseases has been highlighted. However, DFO presents significant limitations in clinical use due to its poor absorption in the gut and very short plasma half-life. To overcome these problems, the feasibility of chitosan/alginate hydrogels as prolonged delivery systems of DFO was investigated. Hydrogel alone ...

To study the release of liposome-associated drugs into hydrogels, we designed and synthesized two pH-sensitive rhodamine derivatives to use as model compounds of different lipophilicities. The dyes were fluorescent when in the free form released from liposomes into the chitosan hydrogel, but not when incorporated within liposomes. The effect of liposomal composition, surface charge and vesicle ...

The present study is aimed at developing novel type of interpenetrating polymeric network (IPN) hydrogels of chitosan with poly(acrylic acid) for the controlled release of amphetamine drug. IPN hydrogels were synthesized by simultaneous polymerization/crosslinking of acrylic acid monomer in the presence of chitosan and crosslinker. The swelling properties and in vitro drug release characteristi...

background: the development of injectable sustained-release products are of great interest to veterinary pharmaceuticals and animal health business. recently, great attention has been paid to in situ gel-forming chitosan/beta-glycerophosphate (chitosan/β-gp) solutions due to their good biodegradability and thermosensitivity. objectives: the general aim of this study was to prepare a novel in si...