Purpose: The aim of this work was to synthesize superporous hydrogels of rosiglitazone using chitosan and to study its swelling behaviour for application as a gastroretentive drug delivery system. Methods: Chitosan superporous hydrogels were synthesized using glyoxal as a crosslinking agent by gas blowing method. The effect of pH and ionic strength on the swelling ratio was determined. Swelling...

BACKGROUND AND THE PURPOSE OF THE STUDY Many drugs which have narrow therapeutic window and are absorbed mainly in stomach have been developed as gastroretentive delivery system. Rosiglitazone maleate, an anti-diabetic, is highly unstable at basic pH and is extensively absorbed from the stomach. Hence there is a need to develop a gastroretentive system. In this study a superporous hydrogel was ...

Introduction............................................................................................................245 Polymer Swelling ..................................................................................................247 Ideas for Rapid Swelling.......................................................................................248 Superporous Hydrogels ....................

the objective of the present study is to develop and investigate the swelling behavior of ph-sensitive superporous hydrogel (sph) and sph composite (sphc). a novel superporous hydrogel containing poly (methacrylic acid-co-acrylamide) was synthesized from methacrylic acid and acrylamide through the aqueous solution polymerization, using n,n-methylenebisacrylamide as a crosslinker and ammonium pe...

Superporous hydrogels (SPHs) are different from superabsorbent polymers (SAPs) in that SPHs swell fast, within minutes, to the equilibrium swollen state regardless of their size. The fast swelling property is based on water absorption through open porous structure by capillary force. The poor mechanical strength of SPHs was overcome by developing the second-generation SPH composites (SPHCs) and...

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Hydrogels are crosslinked polymers with the ability to swell in an aqueous medium. Crosslinking in hydrogels occurs by chemical or physical means depending on the polymer properties and experimental conditions. Owing to a large variety in chemical structure and crosslinking methods, various hydrogels have been prepared for various applications in pharmaceutical and biomedical fields. This chapt...

Superporous hydrogels (SPHs) were originally developed as a novel drug delivery system to retain drugs in the gastric medium. These systems should instantly swell in the stomach and maintain their integrity in the harsh stomach environment, while releasing the pharmaceutical active ingredient. For years, the synthetic features and properties of these SPH materials have been modified and improve...

Superporous hydrogels (SPHs), based on poly(2-hydroxyethyl methacrylate) (PHEMA), were prepared by adding minute amounts of an ioncomplexable hydrophilic acrylic acid. PHEMA SPHs are generally strong, but their swelling is minimal. To improve the swelling, different poly(HEMA-coacrylic acid) hydrogels were polymerized and crosslinked, then physically treated with divalent calcium and trivalent ...