The invention pertains to methods of treating alloys, particularly, biodegradable alloys containing Mg, Zn or Fe. The alloys can be treated with at least one of the following procedures: mechanical polishing, anodization, and polymer coating. Advantageously, methods provided herein enhance the anti-thrombogenicity of the alloy surface. Such materials can be used for preparing biomedical devices, such as endovascular implants, vascular implants, drug-eluting stents, orthopedic prostheses, or implantable chips. Methods of treating a subject by implanting the biomedical devices into the subject are also provided.

A medical device is provided, comprising: an expandable tubular member comprising a plurality of elements forming a sidewall, wherein each of the elements crosses one or more other elements and a plurality of pores are formed among the elements in the sidewall; wherein an antithrombogenic material is coated over the tubular member such that there is inherently no webbing of the antithrombogenic material between any two elements.

There is provided an object, wherein there are particles on the surface of the object, wherein the amount of particles is in the interval 0.041-6 g/cm.sup.2, wherein the particles comprise palladium in an amount corresponding to 0.02-2 g/cm.sup.2, neodymium in an amount corresponding to 0.001-2 g/cm.sup.2, and gold in an amount corresponding to 0.02-2 g/cm.sup.2, and wherein the particles comprise less than 30 ppm silver, which is considered as silver free. The coating is both biocompatible and antimicrobial and does not suffer from disadvantages associated with silver since the coating is silver free. The coating shows improved action against thrombosis.