title: Novel thrombo-resistant coating based on iron-polysaccharide complex multilayers.
abstract: The biocompatibility of iron-polysaccharide complexes has been well-documented. Herein, a stable thrombo-resistant coating was fabricated by consecutive adsorption of Fe (III) and polysaccharides including heparin (Hep) and dextran sulfate (DS) onto various surface by layer-by-layer self-assembly technique via both electrostatic interaction and chemical complexation process. The absorbance at 350 nm increased linearly with the number of Fe3+/Hep multilayer, indicating the formation of multilayer structure and the uniform coating. Compared with (Fe3+/Hep)10, the (Fe3+/DS/Fe3+/Hep)5 coating was more hydrophilic and stable due to the incorporation of DS. The activated partial thromboplastin time (APTT) and platelet adhesion assays showed that both (Fe3+/Hep)10 and (Fe3+/DS/Fe3+/Hep)5 coated surfaces were anticoagulant. The complexing with ferric ions did not compromise the catalytic capacity of heparin to promote antithrombin(III)-mediated thrombin inactivation. Chromogenic assays for heparin activity proved definitively that the inhibition of locally produced thrombin was contributed to the thromboresistance of the surface-bound heparin. The surface with Hep or DS as the outmost layer showed stronger anticoagulant activity than Fe3+, indicating that the outermost layer of the coating played a key role in anticoagulant activity. The utilization of dextran sulfate/heparin surfaces was more advantageous than merely the heparin surface for improving blood-contacting medical devices for long-term usage.
authors.affiliation: Nanomedicine and Biosensor Laboratory, Bio-X Center, and State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), Harbin Institute of Technology, Harbin, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Liu
authors.forename: Xiuli
authors.initials: X
authors.lastname: Yue
authors.forename: Zhifei
authors.initials: Z
authors.lastname: Dai
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.forename: Lei
authors.initials: L
authors.lastname: Xing
authors.forename: Zhengbao
authors.initials: Z
authors.lastname: Zha
authors.forename: Shaoqin
authors.initials: S
authors.lastname: Liu
authors.forename: Yu
authors.initials: Y
authors.lastname: Li
mesh_terms: D000327:Adsorption; D000497:Alloys / Q000737:chemistry; D000990:Antithrombin III / Q000737:chemistry; D001672:Biocompatible Materials / Q000008:administration & dosage / Q000138:chemical synthesis / Q000737:chemistry*; D004355:Drug Stability; D005290:Ferric Compounds / Q000008:administration & dosage / Q000138:chemical synthesis / Q000737:chemistry*; D006493:Heparin / Q000008:administration & dosage / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D010314:Partial Thromboplastin Time; D010973:Platelet Adhesiveness / Q000187:drug effects; D011517:Prothrombin Time; D012965:Sodium Chloride; D013057:Spectrum Analysis
chemical_list: D000497:Alloys; D001672:Biocompatible Materials; D005290:Ferric Compounds; C013616:nitinol; D012965:Sodium Chloride; D000990:Antithrombin III; D006493:Heparin