Fabrication and characterization of heparin functionalized membrane-mimetic assemblies.
A membrane-mimetic assembly incorporating surface bound heparin was fabricated as a system to improve the hemocompatibility of blood-contacting devices. As a model system, heparin was chemically modified by end-point conjugation to biotin and immobilized onto membrane-mimetic thin films via biotin-streptavidin interactions. Heparin surface density, determined by radiochemical titration, confirmed that surface density was directly related to the molar concentration of biotinylated lipid within the assembled membrane-mimetic film. The capacity of surface bound heparin to promote ATIII-mediated thrombin inactivation was investigated in a parallel plate flow chamber under simulated venous and arterial wall shear rates of 50 and 500 s(-1), respectively. Significantly, we observed that the rate of thrombin inactivation approached a maximum at a heparin surface concentration greater than 4.4 pmol/cm(2) (61 ng/cm(2)). In the process, mass transport limited regimes were identified for heparin potentiated thrombin inactivation under both simulated venous and arterial conditions.
Tseng
Po-Yuan
PY
School of Chemical Engineering, Georgia Institute of Technology, Atlanta, 30320, USA.
Rele
Shyam M
SM
Sun
Xue-Long
XL
Chaikof
Elliot L
EL
D000990:Antithrombin III / Q000378:metabolism; D001672:Biocompatible Materials / Q000737:chemistry* / Q000378:metabolism; D032701:Biomimetics; D001710:Biotin / Q000378:metabolism; D001777:Blood Coagulation; D006493:Heparin / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D008422:Materials Testing; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism; D011108:Polymers / Q000737:chemistry / Q000378:metabolism; D013499:Surface Properties; D013917:Thrombin / Q000378:metabolism; D013918:Thrombin Time
D001672:Biocompatible Materials; D010743:Phospholipids; D011108:Polymers; D001710:Biotin; D000990:Antithrombin III; D006493:Heparin; D013917:Thrombin