Polypyrrole: A drug-eluting membrane for coronary stents

An approach to reducing restenosis after coronary angioplasty is the use of drug-eluting stents (DES), which release, usually over a period of 1 month, a bioactive molecule that interferes with the biological processes responsible for restenosis. Given its biocompatibility and ease of electrochemical synthesis in aqueous medium, we investigated the viability of polypyrrole (pPy) directly electrosynthesized on a metal surface in the presence of an anionic drug as electrolyte. The drug, which is incorporated during the electrosynthesis of p-doped polypyrrole, remains partly entrapped after the discharge of the polymer to the neutral form and can then be released over several days, a suitable time range for drug-eluting stents.