title: Plasma-assisted heparin conjugation on electrospun poly(L-lactide) fibrous scaffolds.
abstract: Heparin conjugation on poly(L-lactide) fibrous scaffolds fabricated by electrospinning was accomplished by surface functionalization with amine (-NH2) groups using a sequential treatment with Ar-NH3 and H2 plasmas. The density of the incorporated -NH2 groups was determined by combining a chemical derivatization method with X-ray photoelectron spectroscopy. The time of Ar-NH3 plasma treatment significantly affected the N/C, -NH2 /N, and -NH2 /C fractions, whereas the plasma power, Ar-NH3 gas composition, and time of H2 plasma treatment only influenced the -NH2 /N and -NH2 /C fractions. Scaffold surface functionalization by -NH2 groups significantly increased the amount of covalently bonded heparin compared to a hydrolysis method. The function of immobilized heparin was confirmed by the decrease of platelet attachment during the exposure of the scaffolds to blood from Sprague-Dawley rats. In vitro experiments with bovine aorta endothelial cells demonstrated that heparin conjugation enhanced cell infiltration through the fibrous scaffolds, regardless of the amount of covalently immobilized heparin.
authors.affiliation: Department of Mechanical Engineering, University of California, Berkeley, California, 94720.
authors.forename: Q
authors.initials: Q
authors.lastname: Cheng
authors.forename: K
authors.initials: K
authors.lastname: Komvopoulos
authors.forename: S
authors.initials: S
authors.lastname: Li
mesh_terms: D000641:Ammonia / Q000494:pharmacology; D000818:Animals; D001128:Argon / Q000494:pharmacology; D001547:Benzaldehydes / Q000737:chemistry; D001792:Blood Platelets / Q000187:drug effects / Q000648:ultrastructure; D002417:Cattle; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects; D005453:Fluorescence; D006493:Heparin / Q000494:pharmacology*; D058626:Plasma Gases / Q000494:pharmacology*; D010973:Platelet Adhesiveness / Q000187:drug effects; D011091:Polyesters / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D001547:Benzaldehydes; D058626:Plasma Gases; D011091:Polyesters; C028384:4-(trifluoromethyl)benzaldehyde; C033616:poly(lactide); D001128:Argon; D000641:Ammonia; D006493:Heparin
keywords: amine groups; conjugation; endothelial cells; heparin; infiltration; plasma treatment; platelets; surface functionalization