Bioengineered surfaces to improve the blood compatibility of biomaterials through direct thrombin inactivation

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Freitas, SC (Author) Other; Cereija, TB (Author) Other; Figueiredo, AC (Author) Other; Osorio, H (Author) Other; Pereira, PJB (Author) Other; Mário Adolfo Barbosa (Author) FEUP; Martins, MCL (Author) Other

Journal

Title: Acta Biomaterialia

Vol. 8 No. 3

Pages: 4101-4110

ISSN: 1742-7061

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 6 Citations

Scopus - 6 Citations

Other information

Authenticus ID: P-002-40Y

DOI: 10.1016/j.actbio.2012.07.020

Abstract (EN): Thrombus formation, due to thrombin generation, is a major problem affecting blood-contacting medical devices. This work aimed to develop a new strategy to improve the hemocompatibility of such devices by the immobilization of a naturally occurring thrombin inhibitor into a nanostructured surface. Boophilin, a direct thrombin inhibitor from the cattle tick Rhipicephalus microplus, was produced as a recombinant protein in Pichia pastoris. Boophilin was biotinylated and immobilized on biotin-terminated self-assembled monolayers (SAM) via neutravidin. In order to maintain its proteinase inhibitory capacity after surface immobilization. boophilin was biotinylated after the formation of a boophilin-thrombin complex to minimize the biotinylation of the residues involved in thrombin-boophilin interaction. The extent of boophilin biotinylation was determined using matrix-assisted laser desorption/ionization-time of flight/time of flight mass spectrometry. Boophilin immobilization and thrombin adsorption were quantified using quartz crystal microbalance with dissipation. Thrombin competitive adsorption from human serum was assessed using I-125-thrombin. Thrombin inhibition and plasma clotting time were determined using spectrophotometric techniques. Boophilin-coated SAM were able to promote thrombin adsorption in a selective way, inhibiting most of its activity and delaying plasma coagulation in comparison with boophilin-free surfaces, demonstrating boophilin's potential to improve the hemocompatibility of biomaterials used in the production of blood-contacting devices.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10