Selectively coating luminal surfaces of stents

Abstract

With abluminal side of a stent masked, the luminal side of the stent is selectively coated with a substance, such as an anti-coagulant, a platelet inhibitor and/or a pro-healing substance. The stent can be masked by inserting it into a rigid mandrel chamber or by compressing a masking sleeve onto the outer side of the stent. A spray nozzle inserted into the masked stent spray coats the substance onto the luminal side. The sprayed coating can be cured onto the stent such as by inserting an electrical-resistance heater bar into the stent.

1 - 16 . (canceled) 
     
     
         17 . A stent coating assembly, comprising:
 a support element in which a stent can be placed, the support element capable of being adjusted from a large diameter to a small diameter to compress against an abluminal side of the stent and to mask the stent during an application of a coating substance.   
     
     
         18 . The assembly of  claim 17 , wherein the support includes an elastic membrane for being compressed against the abluminal side of the stent such that the membrane can at least partially protrude into gaps between struts of the stent for masking at least a segment of sidewalls of the struts. 
     
     
         19 . The assembly of  claim 17  additionally including a nozzle for penetrating into the stent for application of a coating substance to a luminal side of the stent. 
     
     
         20 . The support assembly of  claim 17 , further including
 a chamber, comprising:
 the support element, 
 an opening at a proximal end of the chamber for inserting the stent into, and removing the stent from the chamber, 
 a shoulder disposed at a chamber distal end and having an inner diameter less than the small diameter, and 
 a pocket disposed distally of the shoulder. 
   
     
     
         21 . The support assembly of  claim 20 , further including a drive mechanism configured for advancing a spray nozzle or heating element into the chamber while the stent occupies the chamber. 
     
     
         22 . The support assembly of  claim 21 , wherein the spray nozzle is a pin spray. 
     
     
         23 . The support assembly of  claim 22 , wherein the spray nozzle is configured for producing a circular spray pattern. 
     
     
         24 . A chamber, comprising:
 a support element capable of being adjusted from a large diameter to a small diameter to compress against an abluminal side of a stent placed in the chamber;   an opening at a proximal end of the chamber for inserting the stent into, and removing the stent from the chamber;   a shoulder disposed at a distal end of the chamber and having an inner diameter less than the small diameter, and   a pocket disposed distally of the shoulder; and   a nipple disposed distally of the pocket for placing a fluid source in fluid communication with the chamber.   
     
     
         25 . The support assembly of  claim 24 , wherein the fluid source is heated air for drying the stent after applying a coating. 
     
     
         26 . A stent coating assembly, comprising:
 a chamber for receiving a stent, the chamber including a support element capable of being adjusted from a large diameter to a small diameter to compress against an abluminal side of the stent;   a pocket positioned at an end of the chamber such that an opening diameter of the pocket is smaller than a diameter of the chamber so as to prevent the stent from penetrating into the pocket; and   a coating applicator configured to be inserted into the chamber for coating the stent.   
     
     
         27 . The assembly of  claim 26 , wherein the support element is configured to mask an abluminal side of the stent during application of a coating composition to a luminal side to the stent. 
     
     
         28 . The assembly of  claim 26 , wherein the length of the chamber is equal to or larger than the length of the stent. 
     
     
         29 . The assembly of  claim 26 , wherein the chamber includes a channel for allowing gas to be applied into the chamber. 
     
     
         30 . The assembly of  claim 26 , additionally comprising a heating element circumscribing at least a part of the support for providing heat into the chamber. 
     
     
         31 . The assembly of  claim 26 , wherein the coating applicator can be moved back and forth with respect to the chamber. 
     
     
         32 . The assembly of  claim 26 , wherein the coating applicator can be rotated with respect to the stent. 
     
     
         33 . A means for rotating a stent and moving the stent in a linear direction in combination with the assembly of  claim 26 . 
     
     
         34 . The assembly of  claim 26 , further including a nipple disposed distally of the pocket for placing a fluid source in fluid communication with the chamber.