Hydrogel surface

Kretsinger JK, Haines LA, Ozbas B et al (2005) Cytocompatibility of self-assembled ss-hairpin peptide hydrogel surfaces. Biomaterials 26 5177-5186... 

BD Ratner. Hydrogel surfaces. In NA Peppas, ed. Hydrogels in Medicine and Pharmacy, Vol I Fundamentals. Boca Raton, FL CRC Press, 1986, pp 85-94. 

Figure 29.2 Schematic representation of an aqueous LBL coating layer on the phase separated silicone hydrogels surface in wet and dry conditions.

Objective—to modify hydrogel surface so as to control the rate of drug diffusion for release at a specified rate... 

Because differences in height are hardly palpable on the soft hydrogel surface, the display is covered with a foil equipped with knobs which enhance the palpable edges. 

By the same token, the chemical composition of the substrate may play a major role in protein adsorption, since highly hydrophilic (hydrogel) surfaces tend to adsorb plasma proteins reversibly with little damage, whereas hydrophobic surfaces cause strong and partially irreversible adsorption leading to extensive damage of adsorbed proteins. 

A qualitative difference in protein adsorption to hydrogel and non-hydrogel surfaces is the apparent preference of certain proteins, especially albumin, for hydrogel surfaces. 

To analyze swelling of immobilized hydrogel surface layers, spectroscopic ellipsometry or QCM-D can be utilized, as described in Section 4.4.7. 

Guvendiren, M., Burdick, J.A. The control of stem cell morphology and differentiation by hydrogel surface wrinkles. Biomaterials 31(25), 6511-6518 (2010)... 

The pure hydrogel washed with water (A) and adsorption with MDEA (B) was observed from the SEM images (Figure 3). The surface of the pure hydrogel bead was smoothed (A) followed by roughening of the PAAM hydrogel surface after adsorption reactions (B). 

The batch adsorption is assumed to be visualized by the application of adsorption isotherm models. The different isotherms give an indication of how the contaminants from MDEA solution interact with the PAAM functional groups and distribute themselves over hydrogel surface. The equilibrium adsorption isotherms of total metal ions as well as organic acid anions were determined at 23°C. The equilibrium MDEA concentration (Ce) for varions uptake capacities of heavy metal ions and HSS anions (qe) were fitted to four standard isotherm models and it was observed that Langmuir isotherm best fitted among all. The maximum adsorption capacity (qmax) valnes obtained from the isotherm model using PAAM... 

As a consequence of the hydrophobic character of PUR and the unmodified PES surface, platelets have a spread-out form. The hydrogel surface is, on the contrary, almost free of platelets which, in the case of adhesion, exerts a spherical form without formation of pseudopodia. 

IPNs and gradient IPNs based on polyether-urethane-urea (PEUU) block copolymers and acrylamide, 2-hydroxyethyl methacrylate (HEMA), or N-vinyl-2-pyrrolidone. Intended for biomedical uses, such compositions created high-strength, water-absorbing hydrogel surfaces showing good blood compatibility. 

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