title: Synthesis and evaluation of heparin immobilized "side-on" to polystyrene microspheres coated with end-group activated polyethylene oxide.
abstract: Thiol (-SH) groups were introduced into unfractionated heparin by reaction of carboxyl groups in its uronic acid residues with 3,3'dithiobis(propanoic)hydrazide. Thiolated heparin derivatives were then linked to pyridyl disulfide-activated polyethylene oxide-polypropylene oxide-polyethylene oxide triblocks, which had previously been coated onto the surfaces of 1.15 microm polystyrene microspheres. The heparin immobilization reaction was monitored spectrophotometrically as colored pyridine-2-thione was released. In addition, the zeta potentials of uncoated, triblock-coated, and heparin-containing microsphere suspensions were recorded to demonstrate the successful attachment of heparin on the surface. However this "side-on" attachment of heparin to pendant, polyethylene oxide chains did not significantly increase the anticoagulant or anti-Factor Xa activity of microsphere suspensions.
authors.affiliation: School of Chemical, Biological and Environmental Engineering, Oregon State University, Corvallis, OR 97331, USA.
authors.forename: Pranav
authors.initials: P
authors.lastname: Joshi
authors.forename: Karl F
authors.initials: KF
authors.lastname: Schilke
authors.forename: Allyson
authors.initials: A
authors.lastname: Fry
authors.forename: Joseph
authors.initials: J
authors.lastname: McGuire
authors.forename: Karyn
authors.initials: K
authors.lastname: Bird
mesh_terms: D000327:Adsorption; D000818:Animals; D000925:Anticoagulants / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D001777:Blood Coagulation / Q000187:drug effects; D006493:Heparin / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D006834:Hydrazines / Q000737:chemistry; D008863:Microspheres; D011092:Polyethylene Glycols / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*
chemical_list: D000925:Anticoagulants; D006834:Hydrazines; D011137:Polystyrenes; C029424:hydrazine; D011092:Polyethylene Glycols; D006493:Heparin