Molecularly designed surfaces for blood deheparinization using an immobilized heparin-binding peptide

• Type: Article in International Scientific Journal
• Date: 2009

Authors

Martins, MCL (Author) Other; Curtin, SA (Author) Other; Freitas, SC (Author) Other; Salgueiro, P (Author) Other; Ratner, BD (Author) Other; Mário Adolfo Barbosa (Author) FEUP

Journal

Title: Journal of Biomedical Materials Research - Part A

Vol. 88A

Pages: 162-173

ISSN: 1549-3296

Publisher: Wiley-Blackwell

Indexing

ISI Web of Knowledge - 17 Citations

Scopus - 17 Citations

Other information

Authenticus ID: P-003-QTH

DOI: 10.1002/jbm.a.31849

Abstract (EN): Systemic heparinization, used during haemodialysis to prevent blood clotting on the extracorporeal circuit, leads to a high incidence of hemorrhagic complications. The adverse reactions associated with heparin neutralization using protamine sulphate justify the development of an alternative system for blood deheparinization. The main objective of this work is to design nanostructured surfaces with the capacity to bind heparin from blood in a selective way. A heparin-binding polypeptide, composed of L-lysine and L-leucine (pKL), was synthesized and immobilized, in different concentrations, onto self-assembled monolayers (SAMs) terminated with tetra(ethylene-glycol) (EG4 SAMs). Immobilization was performed using 1 fixed Concentration of pKL after surface activation to different degrees using a range of CDI (N,N'-carbonyl-diimidazole concentrations. Results demonstrated that the presence of pKL increases heparin adsorption to EG4-SAMs, independently of the pKL concentration and the way of immobilization (adsorption or covalent bound). Selectivity towards heparin Was successfully achieved on SAMs with low concentration,,; of immobilized pKL (9-17% of pKL). Surfaces were characterized using ellipsometry, contact angle measurements, Fourier transform infrared reflection absorption spectroscopy (IRAS), atomic force microscopy, and X-ray photoelectron spectroscopy. Heparin adsorption was assessed using IRAS and N-sulphonate-(35)S-heparin. Therefore, this study Could give a good contribution for the design of blood deheparinization devices. (C) 2008 Wiley Periodicals, Inc. J Biomed Mater Res 88A: 162-173, 2009

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12