Biomaterial polymer grafting

This contribution will provide a review of polylectrolytes as biomaterials, with emphasis on recent developments. The first section will provide an overview of methods of synthesizing polyelectrolytes in the structures that are most commonly employed for biomedical applications linear polymers, crosslinked networks, and polymer grafts. In the remaining sections, the salient features of polyelectrolyte thermodynamics and the applications of polyelectrolytes for dental adhesives and restoratives, controlled release devices, polymeric drugs, prodrugs, or adjuvants, and biocompatibilizers will be discussed. These topics have been reviewed in the past, therefore previous reviews are cited and only the recent developments are considered here. 

Yamato M, Konno C, Utsumi M, Kikuchi A, Okano T (2002) Thermally responsive polymer-grafted surfaces facilitate patterned cell seeding and co-culture. Biomaterials 23(2) 561-567... 

In dentistry, silicones are primarily used as dental-impression materials where chemical- and bioinertness are critical, and, thus, thoroughly evaluated.546 The development of a method for the detection of antibodies to silicones has been reviewed,547 as the search for novel silicone biomaterials continues. Thus, aromatic polyamide-silicone resins have been reviewed as a new class of biomaterials.548 In a short review, the comparison of silicones with their major competitor in biomaterials, polyurethanes, has been conducted.549 But silicones are also used in the modification of polyurethanes and other polymers via co-polymerization, formation of IPNs, blending, or functionalization by grafting, affecting both bulk and surface characteristics of the materials, as discussed in the recent reviews.550-552 A number of papers deal specifically with surface modification of silicones for medical applications, as described in a recent reference.555 The role of silicones in biodegradable polyurethane co-polymers,554 and in other hydrolytically degradable co-polymers,555 was recently studied. 

The suitable materials for the above mentioned domains are polymers, metals and ceramics. Among these, polymers play an important role. Even the polymers have a lot of remarkable properties that could be used in biomaterials design, the interaction between these artificial materials and tissues and blood could create serious medical problems such as clot formation, activating of platelets, and occlusion of tubes for dialysis or vascular grafts. In the last few years, novel techniques of synthesis have been used to correlate desirable chemical, physical and biological properties of biomaterials. 

The biomaterial was dispersed in a definite amount of water. Ceric ammonium nitrate and nitric acid are then to be added slowly to the reaction mixture. Then, the monomer acrylic acid should be added drop wise to the reaction mixture. The reaction flask is to be placed in a water bath at 10-85°C for various time periods under stirring by a magnetic stirrer. After a definite time period, the reaction mixture is to be filtered and the homo-polymer should be removed with excess water. The grafted sample is to be dried to a constant weight and used for sorption studies. From the increase in weight of the biomaterial, the percentage of grafting should be calculated as follows ... 

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