Fibrous hydrogels

The activities of crude lipase and physically adsorbed lipases in the PAA/PVA fibrous hydrogel membrane (3.5 COOH/OH molar ratio) in pH 4 buffer solution were monitored over time (Figure 5). It took about 5min for the crude lipase (Figure 5a), and about one hour for the adsorbed lipases (Figure 5b) to reach their maximum activities, respectively. The highest activity of adsorbed lipases was 5.5 U/mg lipase, which was about 75% of that of crude lipase. 

Hirasa 0, Morishita Y, Onomura R, Ichijo H, Yamauchi A. Preparation and mechanical properties of thermo-responsive fibrous hydrogels made from poly(vinyl methyl ether)s. Kobunshi Ronbunshu 1989 46(11) 661—665. 

Jin, X. and Y.-L. Hsieh (2005b). pH-responsive swelling behavior of poly(vinyl alcohol)/poly(acrylic acid) bi-component fibrous hydrogel membranes. Polymer 46(14) 5149-5160. 

SOCA - INTRODUCTION] (Vol21) Hydrogel fibrous composites... 

Jeong and coworkers have reported peptide-based thermo-gelling systems using PEG-b-polyAla as an injectable cellular scaffold [315]. The polymer aqueous solution undergoes sol-gel transition as temperature increases. The fraction of the p-sheet structure of the poly Ala dictated the population and thickness of fibrous nanostructure in the hydrogel, which affected the proliferation and protein... 

Fig. 21. Thermo-mechanical response of fibrous PVME hydrogel...

Sundararaghavan HG, Metter RB, Burdick JA (2010) Electrospun fibrous scaffolds with multiscale and photopattemed porosity. Macromol Biosci 10(3) 265-270 Vanderhooft JL et al (2009) Rheological properties of cross-linked hyaluronan-gelatin hydrogels for tissue engineering. Macromol Biosci 9( l) 20—28... 

Photolithography and microfabrication are techniques used for the formation of scaffolds of specific shape and with distinct surface properties. Three-dimensional scaffolds are composed of hydrogels like biodegradable lactide/glycolic acid copolymers or nonbiodegradable polydimethylsiloxane. In the case of lactide/glycolic acid copolymers, the polymer is formed into a fibrous... 

Li and Hsieh (//) C. rugosa lipase hydrogel fibrous membranes (PAA, PVA electrospinning)... 

Preparation of ultra-fine PAA/PVA hydrogel fibrous membrane and cast film... 

Both physical absorption and covalent bonding mechanisms were investigated for immobilizing the lipase onto the PAA/PVA hydrogel fibrous membrane. For the covalent bonding mechanism, EDC was used as the coupling reagent. All measurements were performed in triple. 

The behavior of stem cells in a 3D environment is well worth studying, since most practical applications of tissue repair and regeneration are accomplished by materials with a 3D structure, such as scaffolds, hydrogels, fibrous meshes, and microspheres. 

Focus has changed with time from nonabsorbable to absorbable polymers. Absorbable polymers typically take the form of fibrous meshes, porous scaffolds, or hydrogels. If the polymer can degrade at a controlled rate, the body s own cells can infiltrate the matrix and replace the polymer space with natural tissue. The use of an absorbable polymer can have many advantages, such as the following ... 

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