Hydrogels stability

A.L. Crumbliss, J.Z. Stonehuerner, R.W. Henkens, J. Zhao, and J.P. O Daly, A carrageenan hydrogel stabilized colloidal gold multi-enzyme biosensor electrode utilizing immobilized horseradish peroxidase and cholesterol oxidase/cholesterol esterase to detect cholesterol in serum and whole blood. Biosens. Bioelectron. 8, 331-337 (1993). 

When the amount of TPABr in the initial hydrogel decreases, the stability of the MFI product decreases too and the co-cristallization of MFI and quartz is observed after short periods of time. It is possible to obtain MFI products starting from various ratios of Al/Fe in the hydrogel. The crystallization time is a function of the initial TPABr, aluminium and iron content. The presence of A1 in the hydrogel stabilizes... 

Rocasalbas, G., et al. Laccase-assisted formation of bioactive chitosan/gelatin hydrogel stabilized with plant polyphenols. Carbohydr. Polym. 92(2), 989-996 (2013)... 

Unfortunately, reliable data on the equilibrium swelling and long-term stability of hydrogels obtained by this method are not available. It should be noted that crosslinking of polymers with metal ions is one of the few reactions which can be carried out directly in the soil medium, which is efficiently used, e.g., in oil recovery [65, 66]. 

Akiyoshi K, Kobayashi S, Shichibe S et al (1998) Self-assembled hydrogel nanoparticle of cholesterol-bearing pullulan as a carrier of protein drugs Complexation and stabilization of insulin. J Control Release 54 313-320... 

PVA must be cross-linked in order to be useful for a wide variety of applications. A hydrogel can be described as a hydrophilic, cross-linked polymer, which can sorbe a great amount of water by swelling, without being soluble in water. Other specific features of hydrogels are their soft elastic properties, and their good mechanical stability, independent of the shape (rods, membranes, microspheres, etc.). 

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