Heparin-coated poly polymerization

To make nanoparticles able to escape complement activation, Passirani et alJ" proposed to coat nanospheres with heparin. This compound, which is a polysaccharide, is a physiological inhibitor of complement activation in vivo. Heparin-coated poly(methylmetha-crylate) nanoparticles were prepared by emulsion polymerization. In the method, the radical polymerization of methylmethacrylate was initiated by heparin according to an original method involving cerium ions and allowing heparin to covalently attach to poly(methyl-methacrylate). 

Na K, Kim S, Park K, Kim K, Woo DG, Kwon IC, Chung HM, Park KH (2007) Heparin/poly(L-lysine) nanoparticle-coated polymeric microspheres for stem-cell therapy. J Am Chem Soc 129 5788-5789. 

PVPyrH Poly-4-vinylpyridine (PVPyr) prepared by conventional persulfate catalyzed polymerization was dissolved in ethyl alcohol or methyl Cellosolve (2 to 3% solution) for application to polyester film substances. These films adsorb heparin from solutions of sodium heparin to produce anticoagulant surfaces (PVPyrH). Films were painted on, or spread by knife coating. 

Interest continues in the binding of heparin to polymers in an attempt to produce non-thrombogenic surfaces. This has been the aim in the use of glutaralde-hyde-protein complexes as coatings for latex rubber and polyurethanes. Glutaraldehyde has also been used to bind antibodies to partially hydrolysed polyamide surfaces for enzyme-linked radioassay techniques. One of the few examples of direct polymerization (as opposed to surface modification) in an attempt to produce polymers having improved compatibility involves the use of 2-methacryloyloxyethylphosphoryl choline in the formation of homopolymers and copolymers with methyl methacrylate. An isocyanato-urethane methacrylate has been synthesized from 2-hydroxyethyl methacrylate in connection with dental materials research in which the preparation of poly functional monomers for improvement of interfacial bonding with tooth tissue is a topic of some interest. 

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