Methyl-beta-cyclodextrin modified vascular prosthesis: Influence of the modification level on the drug delivery properties in different media

A textile polyester vascular graft was modified with methyl-beta-cyclodextrin (Me beta CD) to obtain a new implant capable of releasing antibiotics directly in situ at the site of operation over a prolonged period and thereby prevent post-operative infections. We investigated the influence of the curing parameters (time and temperature) that allow control of the degree of functionalization (DF) of the support by Me beta CD. The inclusion of ciprofloxacin (CFX) in the Me beta CD cavity was observed in solution by two-dimensional H-1 NMR spectroscopy. The amount of CFX loaded on the modified graft increased with DF. Depending on the release medium (water, phosphate-buffered saline, or human plasma) and the DF of the prostheses, different kinetic profiles of release of CFX were obtained. The sustained release of CFX in human plasma was shown by microbiological assays that indicated prolonged antimicrobial activity against Staphylococcus aureus and Escherichia colt. Viability tests demonstrated the non-toxicity of Me beta CD to an epithelial cell line (HPMEC), although a decrease in endothelial cell number was observed on the functionalized prosthesis, probably due to the roughness of the coating and also to the nature of the Me beta CD polymer present on the surface of the fibers. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.