Electrocoating of stainless steel coronary stents for extended release of paclitaxel

Abstract

Nonbiodegradable polymer coating based on N-(2-carboxyethyl)pyrrole (PPA) and butyl ester of PPA (BuOPy) were successfully electrodeposited on a stainless steel stent surface using cyclic voltammetry. Chemical composition of the coating was examined by X-ray photoelectron spectroscopy. Polymer stability was examined by immersing the coated stent into 1:1 solution of fetal calf serum:seline solution up to 1 year and implantation subcutaneously in mouse for 1 week. Morphology changes were then recorded by scanning electron microscopy. Paclitaxel loading was carried out by immersion into drug solution and its release was detected by HPLC. The results show that thin (single micrometers), uniform coating with various morphology and hydrophobicity can be created by electrochemical deposition. The polymer did not show significant histopathological or morphological changes in vitro and in vivo. The surface properties allow loading appropriate amounts of paclitaxel and release it slowly up to a month.

Oligonucleotide biofunctionalization enhances endothelial progenitor cell adhesion on cobalt/chromium stents

“…Employment of metal stents has emerged as an effective treatment for occlusive vascular disease, overcoming the main limitation of angioplasty alone and providing mechanical scaffold to the vessel wall. Still, this method is not free from complications as stent implantation causes wall injury and the metal surface constitutes a thrombogenic foreign body . Thus, restenosis and thrombosis remain a severe complication, hampering the long‐term clinical success of bare metal stents.…”

Electrochemical Coating of Medical Implants

“…Taking into account the chemical and physical behavior of the ED precursors, allows controlling and tuning the structure of the electrodeposited coating and adjusting it for different purposes and specifically for medical implants. Electrochemical co-deposition of polypyrrole derivatives on a stent surface was shown by Okner et al 115 ( Fig. 5).…”

Electrohydrodynamic Jetting Behaviour of Polyhedral Oligomeric Silsesquioxane Nanocomposite

“…Various approaches have been previously used to include polymers in stents including dipping [36,37], spraying [36], solution casting, and chemical vapor deposition [38,39]. Solvent-based coating techniques have some disadvantages, such as bridging, pooling and lack of uniformity or disability to apply different thicknesses with precise process control, in particular when coating thicknesses of 50.5 mm are to be prepared [39][40][41]. Chemical vapor deposition methods require high temperature and pressure environments and complex equipment [40].…”

“…Solvent-based coating techniques have some disadvantages, such as bridging, pooling and lack of uniformity or disability to apply different thicknesses with precise process control, in particular when coating thicknesses of 50.5 mm are to be prepared [39][40][41]. Chemical vapor deposition methods require high temperature and pressure environments and complex equipment [40]. Considering these disadvantages, a new approach is needed to apply a thin polymeric film on the metallic stent surface with a high degree of precision.…”