Open AccessBinding Kinetics of Thrombin and Antithrombin III with Immobilized Heparin Using a Spacer
Author(s) -
Youngro Byun,
Harvey Jacobs,
Sung Wan Kim
Publication year - 1992
Publication title -
asaio journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.961
H-Index - 66
eISSN - 1538-943X
pISSN - 1058-2916
DOI - 10.1097/00002480-199207000-00117
Subject(s) - heparin , antithrombin , chemistry , thrombin , polymer , kinetics , covalent bond , chromatography , polymer chemistry , substrate (aquarium) , low molecular weight heparin , organic chemistry , biochemistry , platelet , physics , oceanography , quantum mechanics , immunology , biology , geology
The immobilization of heparin onto polymeric surfaces using a hydrophilic spacer was effective in curtailing surface induced thrombus formation. In this study, the binding kinetics of immobilized heparin with antithrombin III (ATIII) and thrombin were investigated. Low molecular weight heparin (molecular weight, 6,000 daltons) was fractionated on an ATIII affinity column, and it was immobilized onto a styrene/p-amino styrene random co-polymer surface via hydrophilic spacer groups. This polymer substrate was coated onto glass beads (diameter range, 0.088-0.105 mm). PEO (molecular weight 3,400), modified by tolylene diisocyanate, was covalently coupled as a spacer group, followed by heparin. The bioactivity of immobilized heparin was approximately 16.2%, relative to free heparin, and nearly 1:1 binding between heparin and PEO was calculated. The binding constants of immobilized heparin and ATIII, and immobilized heparin and thrombin, were 0.958 x 10(7) M-1 and 1.76 x 10(8) M-1, respectively. The immobilized heparin bound with both ATIII and thrombin, and the binding mechanism was similar to that of free heparin.