Hydrogels fibers

Gitsov et al 10) produced a nanoreactor fi om laccase and linear poly(ethylene oxide)-dendritic poly(benzyl ether) diblock copolymers. A notable feature of this system is the presence of hydrophobic dendritic pockets that increase the local concentration of water-insoluble organic compounds near the active site where they are oxidized. Li and Hsieh (77) employed a hydrogel fiber membrane, with a large surface area and improved organic solvent solubility in order to facilitate lipase reactions. He (72) grafted lipase onto silica particles, which permitted him to carry out synthesis of polyesters, polycarbonates, polyphosphates, and their copolymers at temperatures up to 150°C. 

Lipase Immobilization on Ultrafine Poly(acrylic acid)-PoIy(vinyl alcohol) Hydrogel Fibers... 

As expected, the amount of lipase adsorbed in hydrogel fibers was much higher than that in the cast films with the same polymer composition because of the much larger specific surface of the fibers. For example, when the adsorption was performed in a pH 7 buffer, the amount of lipase immobilized in the cast film (3.5 COOH/OH molar ratio) was only about 58% of that in the hydrogel fibers of the same polymer composition. 

Figure 4. Amount of lipase physically adsorbed in PAA/PVA (COOH/OH molar ratio = 3.5) hydrogel fibers in buffers with different pH values.

Figure 5, Kinetics of catalytic hydrolysis (30PC, pH 8,5) of olive oil by (a) crude lipase (b) lipases adsorbed by PAA/PVA hydrogel fibers (COOH/OH molar ratio = 5. the lipase adsorption was conducted in pH 4 buffer solution).

The lipase immobilized on the hydrogel fibers by method III showed an activity of 2.4 U/mg lipase in the first cycle, which was about 33% of that of the free lipase. The activities then lowered gradually to 1.5, 1.0, and 0.3 U/mg lipase in the subsequent cyclic measurements (Figure 8). The activity of the second cycle was nearly doubled with method III than that of the physically... 

Molecular Recognition of Chemosensors in a Supramolecular Hydrogel Use of Hydrophobic Micro-domains of Supramolecular Hydrogel Fibers for Discrimination of Phosphate Derivatives. 

Ultrafine hydrogel fibers with dual temperature- and pH-responsive swelling behaviors. /. Polym. ScL, Part A Polym. Chem., 42, 6331-6339. 

Hyaluronic acid [207] Tobramycin, basic FGF and platelet-derived growth factor [208] Scaffold, matrix, membrane, hydrogel, fiber Significantly enhanced wound healing compared with matrix containing only the antibiotic... 

Jin, X. and Y.-L. Hsieh (2005a). Anisotropic dimensional swelling of membranes of ultrafine hydrogel fibers. Macromolecular Chemistry and Physics 206(17) 1745-1751. 

Heo YJ, Shihata H, Okitsu T, Kawanishi T, Takeuchi S. Long-term in vivo glucose monitoring using fluorescent hydrogel fibers. Proceedings of the National Academy of Sciences of the United States of America 2011 108(33) 13399-403. 

---