Surface-modified biomaterials

The white cell adsorption filter layer is typically of a nonwoven fiber design. The biomaterials of the fiber media are surface modified to obtain an optimal avidity and selectivity for the different blood cells. Materials used include polyesters, eg, poly(ethylene terephthalate) and poly(butylene terephthalate), cellulose acetate, methacrylate, polyamides, and polyacrylonitrile. Filter materials are not cell specific and do not provide for specific filtration of lymphocytes out of the blood product rather than all leukocytes. 

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. 

N. Kossovsky, A. Gelman, E. Sponsler, H. Hnatyszyn 1994, (Surface modified nanocrystalline ceramics for drug delivery application), Biomaterials 15, 1201. 

M.J. Ernsting, G.C. Bonin, M. Yang, R.S. Labow, J.P. Santerre, Generation of cell adhesive substitutes using peptide fluoroalkyl surface modifiers, Biomaterials 26 (2005) 6536-6546. 

Ernsting MJ, Labow RS, Santerre JP. Surface modification of a polycarbonate-urethane using a vitamin-E-derivatized fluoroalkyl surface modifier. Journal of Biomaterials Science, Polymer Edition 2003, 14, 1411-1426. 

SMA-based surface architecture fundamentally influences the events and responses of biological substances that approach from the ambient to biomaterial surfaces, thereby directly dominates the overall performance of the surface modifying efforts. 

Gupta, A. K., and Gupta, M. (2005), Cytotoxicity suppression and cellular uptake enhancement of surface modified magnetic nanoparticles, Biomaterials, 26(13), 1565-1573. 

Lin W, Garnett MC, Davies MC, Bignotti F, Ferruti P, Davis SS, Ilium L. Preparation of surface-modified albumin nanospheres. Biomaterials 1997, 18, 559-565. 

M.C. Ilium, L. Long circulating biodegradable 68. poly(phosphazene) nanoparticles surface modified with poly(phosphazene)-poly(ethylene oxide) copolymer. Biomaterials 1997, 18, 1147-1152. 69. 

Varma, H.K., Sreenivasan, K., Yokogawa, Y., and Hosumi, A. (2003) In vitro calcium phosphate growth over surface modified PMMA film. Biomaterials, 24 (2), 297-303. 

Kyomoto M, Moro T, Yamane S, Hashimoto M, Takatori Y, Ishihara K. Poly(ether-ether-ketone) orthopedic bearing surface modified by self-initiated surface grafting of poly(2-methacryloyloxyethyl phosphorylcholine). Biomaterials 2013 34(32) 7829- 39. 

Recently, plasma gas discharge [Khang et al., 1997a] and corona treatment [Khang et al., 1996d] with reactive groups introduced on the polymeric surfaces have emerged as other ways to modify biomaterial surfaces [Lee et al., 1991 1992]. 

Quirk, R.A. et al., Poly(L-lysine)-GRGDS as a biomimetic surface modifier for poly(lactic acid). Biomaterials, 22, 865, 2001. 

Qu XH, Wu Q, Liang J, Qu X, Wang SG, Chen GQ (2005) Enhanced vascular-related cellular affinity on surface modified copolyesters of 3-hydroxybutyrate and 3-hydroxyhexanoate (PHBHHx). Biomaterials 26 6991-7001... 

Both XPS and TOF-SIMS are nowadays standard analytical tools for the determination of biomaterials surface chemistry. Examples of the use of XPS or TOF-SIMS for the analysis of biomimetic polymers include the investigation of different protein " ° and phosphate group modified polymeric surfaces. 

Infection has been reported to often occur when a biomaterial is implanted in a body or inserted in tubular organs as a catheter. Such infection seems to be a result of adhesion of infectious bacteria onto the biomaterial surface. If bacteria adhesion is similar to adhesion of other cells like fibroblasts, occurrence of infection through the material surface may be reduced by modifying the material surface so as to minimize cell adhesion. Such a surface can be obtained by surface grafting of water-soluble polymer chains. However, producing a hydrophilic biomaterial surface by plasma treatment only leads to enhanced cell adhesion as shown in Figure 10 (16). 

Greene, G., Radhakrishna, H. and Tannenbaum, R. 2005. Protein binding properties of surface-modified porous polyethylene membranes. Biomaterials 26 5972-5982. 

Kouvroukoglou, S., Dee, K. C., Bizios, R., Mclntire, L. V., and Zygourakis, K. (2000), Endothelial cell migration on surfaces modified with immobilized adhesive peptides, Biomaterials 21(17) 1725-1733. 

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