Method and apparatus for coating balloon catheters
A coating apparatus for coating the balloon portion of a balloon catheter is described. The coating apparatus includes a rotatable member in which the catheter portion of the balloon catheter is mounted and fixed, and which causes rotation of the balloon catheter. The apparatus also includes a support member in which the distal tip of the catheter is inserted and free to rotate; and a spray nozzle directing sprayed material on the balloon surface. The inventive configuration of the coating apparatus allows the balloon catheter to be rotated along its axis with insubstantial or no wobble, which significantly improves the quality of the coating applied to the surface of the balloon.
1. An apparatus for coating a balloon catheter, the apparatus comprising:
(a) a rotatable member comprising an elongated shape having an elongated split cylindrical configuration with a distal end and a proximal end, a central axis about which the rotatable member can be rotated and which is configured to accommodate and fix a catheter portion of a balloon catheter having a catheter axis so the central axis is aligned with the catheter axis;
(b) a support member, which is aligned with the central axis of the rotatable member, which is configured to hold and allow rotation of a distal tip of the balloon catheter when the catheter portion of the balloon catheter is fixed and rotated in the rotatable member, and wherein the distal end of the rotatable member is separated from the support member by a gap; and
(c) a nozzle capable of delivering coating material in the gap between the distal end of the rotatable member and the support member.
2. The apparatus of claim 1 wherein the elongated split cylindrical configuration is split along its length from proximal to distal ends.
3. The apparatus of claim 2 wherein the rotatable member comprises two half cylinders hinged along one side of the rotatable member.
4. The apparatus of claim 1 wherein the support member comprises a circular grommet.
5. The apparatus of claim 1 wherein the rotatable member has a length in the range of 50 cm to 200 cm.
6. The apparatus of claim 1 wherein the nozzle comprises a spray nozzle.
7. The apparatus of claim 1 further comprising an indeflator.
8. The apparatus of claim 1 further comprising a drive mechanism which causes rotation of the rotatable member, support member, or both.
9. The apparatus of claim 8 wherein the drive mechanism is attached to the proximal end of the rotatable member.
10. The apparatus of claim 1 wherein the support member comprises a low friction material.