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

Abstract

A textile polyester vascular graft was modified with methyl-β-cyclodextrin (MeβCD) 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 MeβCD. The inclusion of ciprofloxacin (CFX) in the MeβCD cavity was observed in solution by two-dimensional (1)H 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 coli. Viability tests demonstrated the non-toxicity of MeβCD 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 MeβCD polymer present on the surface of the fibers.