Chitosan and poly(vinyl alcohol) (PVA) were used to form a semi-interpenetrating polymeric network with glutaraldehyde as the cross-linker. The molecular weight and degree of deacetylation of the chitosan were 612 kDa and 72 %, respectively. The chemical bonds formed by the cross-linking reaction and transition of these bonds in different pH media were investigated. The gelation property of the...

Abstract: Some vinyl hydrogels containing α-amino acid residues (L-phenylalanine, L-valine) were used as polyelectrolyte platforms for the evaluation of the controlled release of two antidepressants (paroxetine and duloxetine). The closer acidity constant (pKa) values of the two drugs show a closer release profile in physiological phosphate buffered saline (PBS) buffer (pH 7.40) and for long pe...

The cover feature image shows a two-dimensional (2D) colorimetric carbon dioxide (CO2) sensor composed of gas-permeable polypropylene film (25 μm thick) and signal transduction hydrogel layer (30 thick). contained pH sensitive chromoionophore to indicate the CO2 induced change, cationic amine further capture through carbamate formation reaction. With this 2D optode, release from yeast-catalyzed...

In this study, several examples of hydrogels and nanocomposite hydrogels based on PVP with different content of montmorillonite nanoclay were prepared. Then, the swelling of hydrogels and kinetics of drug delivery of hydrogel in an environment similar to the body (pH 7.4) were examined. The effect of nanoparticle different percentages on the hydrogel was clearly observed. Then kinetics of drug ...

BACKGROUND The hydrogel based system is found to be rarely reported for the delivery of hydrophobic drug due to the incompatibility of hydrophilicity of the polymer network and the hydrophobicity of drug. This problem can be solved by preparing semi-interpenetrating network of cross-linked polymer for tuning the hydrophilicity so as to entrap the hydrophobic drugs. The current study is to devel...

Phase mask interference lithography was employed to fabricate three-dimensional (3D) hydrogel structures with high surface area on neural prosthetic devices. A random terpolymer of poly(hydroxyethyl methacrylate- ran-methyl methacrylate- ran-methacrylic acid) was synthesized and used as a negative-tone photoresist to generate bicontinuous 3D hydrogel structures at the submicrometer scale. We de...