Protein adsorption and

Andrade, J. D-, Hlady, V. Protein Adsorption and Materials Biocompability A. Tutorial Review and Suggested Hypothesis. Vol. 79, pp. 1-63. 

Chen et al. utUized a direct chemical reaction with a given solution (wet treatment) to modify the surface of the silicone rubber. The presence of a layer of PEO on a biomaterial surface is accompanied by reductions in protein adsorption, and cell and bacterial adhesion. In order to obtain a PEO layer on top of the silicone rabber surface, the surface was firstly modihed by incorporating an Si-H bond using (MeHSiO) , and followed by PEO grafting to the surface using a platinum-catalyzed hydrosilylation reaction. These PEO-modified surfaces were demonstrated by fibrinogen adsorption both from buffer and plasma, as well as albumin adsorption from buffer. Reductions in protein adsorption of as much as 90% were noted on these surfaces. 

Abramson, S., Hofistein, S.T. and Weissmann, G. (1982). Superoxide anion generation by human neutrophils exposed to monosodium urate. Effect of protein adsorption and complement activation. Arth. Rheum. 25, 174-180. 

J. D. Andrade and V. Hiady, Protein adsorption and materials biocompatibility A tutorial review and suggested hypotheses, Adv. Polymer Sci., 79, 1 (1986). 

Many kinds of nonbiodegradable vinyl-type hydrophilic polymers were also used in combination with aliphatic polyesters to prepare amphiphilic block copolymers. Two typical examples of the vinyl-polymers used are poly(/V-isopropylacrylamide) (PNIPAAm) [149-152] and poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) [153]. PNIPAAm is well known as a temperature-responsive polymer and has been used in biomedicine to provide smart materials. Temperature-responsive nanoparticles or polymer micelles could be prepared using PNIPAAm-6-PLA block copolymers [149-152]. PMPC is also a well-known biocompatible polymer that suppresses protein adsorption and platelet adhesion, and has been used as the hydrophilic outer shell of polymer micelles consisting of a block copolymer of PMPC -co-PLA [153]. Many other vinyl-type polymers used for PLA-based amphiphilic block copolymers were also introduced in a recent review [16]. 

Arima Y, Iwata H (2007) Effect of wettability and surface functional groups on protein adsorption and cell adhesion using well-defined mixed self-assembled monolayers. Biomaterials 28 3074-3082... 

Tegoulia VA, Cooper SL (2000) Leukocyte adhesion on model surfaces under flow effects of surface chemistry, protein adsorption, and shear rate. J Biomed Mater Res 50 291-301... 

Scotchford CA, Gilmore CP, Cooper E, Leggett GJ, Downes S (2002) Protein adsorption and human osteoblast-like cell attachment and growth on alkylthiol on gold self-assembled monolayers. J Biomed Mater Res 59 84-99... 

Bale, M.D., Danielson, S.J., Daiss, J.L., Goppert, K.E., and Sutton, R.C. (1989) Influence of copolymer composition on protein adsorption and structural rearrangements at the polymer surface. J. Colloid Interface Sci. 132, 176-1874. 

Some active materials are carriers for drugs (drug delivery systems), some have immobilized peptides to enable cell adhesion or migration, some are degradable by hydrolysis or by specific enzyme action. Some contain bioactive agents (e.g., heparin, thrombomodulin) to prevent coagulation or platelet activation while others incorporate bioactive groups to enhance osteo-conduction. Many include polyethylene oxide to retard protein adsorption and this is perhaps the closest we have come to a kind of inertness. 

A change in the environment of a protein molecule, e.g. adsorption from aqueous solution onto a sorbent surface, may lead to a partial breakdown of its ordered structure, resulting in an increase of conformational entropy. This is a fundamental difference between protein adsorption and the adsorption of flexible polymers, for which attachment to a surface implies a loss of conformational entropy. 

El wing, H., Protein adsorption and ellipsometry in biomaterial research, Biomaterials 1998, 19,397 406... 

Finally, biomedical applications aiming at controlled protein adsorption and cell adhesion on iniferter-driven surface graft architectures, by which a high-throughput screening of biocompatibility can be materialized, are presented. 

A two-dimensional micropatterned tissue can be easily obtained by utihz-ing the inherent differences in cell adhesiveness between different micropatterned photografted regions. This was attained by photoiniferter graft polymerization with a projection mask placed on an iniferter-derivatized surface. Since protein adsorption and cell adhesion are markedly suppressed on nonionic graft polymers, such as polyDMAm, any anchorage-dependent cells such as endothelial cell adhere and proliferate only on nonirradiated surfaces, resulting in the formation of a two-dimensional patterned tissue or cellular sheet (Fig. 24). 

Problems of desorption and loss of activity encountered with natural heparin have led numerous workers to explore synthetic heparin-like polymers or heparinoids, as reviewed by Gebelein and Murphy [475, 514, 515]. The blood compatibility of 5% blended polyelectrolyte/polyfvinly alcohol) membranes was studied by Aleyamma and Sharma [516,517]. The membranes were modified with synthetic heparinoid polyelectrolytes, and surface properties (platelet adhesion, water contact angle, protein adsorption) and bulk properties such as permeability and mechanical characteristics were evaluated. The blended membrane had a lower tendency to adhere platelets than standard cellulose membranes and were useful as dialysis grade materials. 

In contrast, on the surface of the amino-containing polymeric materials, protonated amino groups introduced in a small proportion under physiological conditions, destroy their surrounding hydrogen bonds to produce, here and there, gaps in the network [127, 128]. Thus, the network structures are considered to become more or less unstable. As a consequence, the residence time of protein molecules trapped by these defective networks will be shorter than in the case of polyHEMA or cellulose. On the surface of these amino-containing materials, reversible protein adsorption and desorption, and also replacement (Vroman effect) - or even protein rejection - will become possible. 

In line with the Gibbs adsorption equation (equation 3.33 in chapter 3), the presence of thermodynamically unfavourable interactions causes an increase in protein surface activity at the planar oil-water interface (or air-water interface). As illustrated in Figure 7.5 for the case of legumin adsorption at the n-decane-water interface (Antipova et al., 1997), there is observed to be an increase in the rate of protein adsorption, and also in the value of the steady-state interfacial pressure n. (For the definition of this latter quantity, the reader is referred to the footnote on p. 96.)... 

Exposing polymers to a biological environment elicits a number of reactions such as protein adsorption and cell adhesion. In some cases, the actions of body defenses against a material are planned as part of a strategy. In other situations, the... 

M. Shen, M. S. Wagner, D. G. Castner and T. A. Horbett, Multivariate surface analysis of plasma-deposited tetraglyme for reduction of protein adsorption and monocyte adhesion, Langmuir, 19(5), 2003, 1692-1699. 

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