Removing a solvent from a drug-eluting coating

摘要

A coating device for coating a medical device with a drug-eluting material uses an in-process drying station between coats to improve a drug release profile. The drying station includes a heat nozzle configured for applying a uniform drying gas.

主权项

1. An apparatus for coating a stent including a drying nozzle having a mean flow direction, an inlet that receives an incoming gas stream and an exit that produces a drying gas, comprising:
a mandrel for holding the stent; a sprayer for applying a coating to the stent; and the nozzle including
a chamber including a first side proximal the inlet and distal the exit, a second side distal the inlet and proximal the exit, and walls extending from the first side to the second side;the walls defining an exit region, inlet region and mid-region of the nozzle, the exit region defining a first volume for gas flow from the mid-region to the exit, and the mid-region defining a second volume for gas flow from the inlet region to the exit region;the exit region formed at least in part by first wall portions that converge towards each other in the flow direction;a first diffuser disposed proximal the inlet and distal the exit, the first diffuser forming a first plurality of openings;a second diffuser disposed proximal the exit and distal the first diffuser, the second diffuser forming a second plurality of openings and having a cross-sectional area configured to direct gas over the surface of the stent,wherein during steady state flow the nozzle produces a gas at the exit that has a substantially uniform velocity and temperature profile across the stent.