In recent years the long term results of percutaneous
transluminal angioplasty as a treatment of atherosclerotic
stenoses have markedly improved by the use of drug
coated metallic stents [1, 2]. Due to the requirement of a
decelerated release kinetic and problems with the adhesion
of the coatings, however, the use of an additional
polymer coating is normally inevitable [3]. Polymer
coatings are difficult to apply and carry the risk of
releasing detached particles into the blood due to
insufficient adhesion to the stent surface [3, 4]. Therefore,
the ideal stent surface would be a microstructured
surface that has good adhesion properties, provides depot
volume and provides a decelerated release kinetic. A
common method of surface modification in order to
increase adhesion is grit blasting. Grit blasted surfaces,
however, do not provide depot volume for a drug and the
procedure imposes mechanical stresses, which is problematic
when applying this procedure to damageable
parts like stents. An interesting alternative is given by
chemical etching techniques. Some research has been
performed on the applicability of chemical etching in
order to improve the surface properties of coronary
stents. However due to the low roughness achievable
with mere chemical etching techniques none of these
In recent years the long term results of percutaneoustransluminal angioplasty as a treatment of atheroscleroticstenoses have markedly improved by the use of drugcoated metallic stents [1, 2]. Due to the requirement of adecelerated release kinetic and problems with the adhesionof the coatings, however, the use of an additionalpolymer coating is normally inevitable [3]. Polymercoatings are difficult to apply and carry the risk ofreleasing detached particles into the blood due toinsufficient adhesion to the stent surface [3, 4]. Therefore,the ideal stent surface would be a microstructuredsurface that has good adhesion properties, provides depotvolume and provides a decelerated release kinetic. Acommon method of surface modification in order toincrease adhesion is grit blasting. Grit blasted surfaces,however, do not provide depot volume for a drug and theprocedure imposes mechanical stresses, which is problematicwhen applying this procedure to damageableparts like stents. An interesting alternative is given bychemical etching techniques. Some research has beenperformed on the applicability of chemical etching inorder to improve the surface properties of coronarystents. However due to the low roughness achievablewith mere chemical etching techniques none of these
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