Expandable fluoropolymer device for delivery of therapeutic agents and method of making

1. A method of manufacturing a radially expandable fluid delivery device, comprising:

providing a tube of biocompatible fluoropolymer material having a microstructure of nodes interconnected by fibrils, wherein the microstructure has a predetermined porosity based on an extrusion and expansion forming process;

applying a radial expansion force to the tube to plastically deform the tube by expanding the tube beyond the tube's elastic limit to a predetermined diameter dimension; and

removing the radial expansion force;

wherein the tube is radially inelastic while sufficiently pliable to be collapsible and inflatable from a collapsed configuration to an expanded configuration upon introduction of an inflation force, such that the expanded configuration occurs upon inflation to the predetermined diameter dimension.

2. The method of claim 1 , wherein the step of providing a tube of biocompatible fluoropolymer material comprises the steps of:

creating a billet by blending a mixture of a fluoropolymer and a lubricant and compressing the mixture;

extruding the billet to form an extruded article having a longitudinal axis;

removing the lubricant from the extruded article;

expanding the extruded article to form the tube of biocompatible fluoropolymer material having a microporous structure; and

heat setting the tube.

3. The method of claim 2 , further comprising varying at least one process parameter to achieve a porosity of the tube of biocompatible fluoropolymer material sufficient for a pressurized fluid to permeate through the wall.

4. The method of claim 1 , wherein the step of applying a radial expansion force comprises:

inserting a balloon into the tube; and

inflating the balloon to apply the radial expansion force to the tube.

5. The method of claim 4 , wherein the balloon is expanded by inflation caused by the introduction of a pressurized fluid into the balloon.

6. The method of claim 1 , further comprising:

providing a mold having an internal cavity of predefined size and shape;

positioning the tube within the internal cavity; and

applying the radial expansion force to the tube with a balloon disposed within the tube, while the tube remains positioned in the internal cavity of the mold.

7. The method of claim 1 , wherein an outer surface of the radially expandable fluid delivery device is hydrophilic.

8. The method of claim 1 , wherein an outer surface of the radially expandable fluid delivery device is hydrophobic.

9. The method of claim 1 , wherein an outer surface of the radially expandable fluid delivery device is at least partially hydrophilic and at least partially hydrophobic.

10. The method of claim 1 , wherein the radially expandable fluid delivery device is formed of multiple layers.

11. The method of claim 1 , wherein the radially expandable fluid delivery device has a hydraulic conductivity less than 1000 (cm 4 (dyne*s)*10 12 ).

12. The method of claim 1 , wherein the predetermined porosity is sufficient to allow fluid to pass through at a flow rate of approximately 0.01 ml/min to 100 ml/min.

13. The method of claim 1 , wherein the radially expandable fluid delivery device has a unitary construction of generally homogenous material.

14. The method of claim 1 , wherein the radially expandable fluid delivery device is configured to receive the inflation force being generated by a fluid including a medicinal agent.

15. The method of claim 14 , wherein the medicinal agent is selected from the group consisting of thrombolytics, antibiotics, antisense oligonucleotides, chemotherapeutics, surfactants, diagnostic agents, steroids, vasodilators, vasoconstrictors, and embolic agents.

16. The method of claim 1 , wherein the radially expandable fluid delivery device comprises a microporous wall portion bordering a second wall portion generally impermeable to pressurized fluid providing the inflation force.

17. The method of claim 1 , wherein the radially expandable fluid delivery device comprises a generally impermeable wall portion interposed between a first microporous wall portion and a second microporous wall portion.

18. The method of claim 1 , wherein the radially expandable fluid delivery device comprises a microporous wall portion of the predetermined porosity bordering a second wall portion modified to have a different porosity.

19. The method of claim 1 , wherein the radially expandable fluid delivery device comprises a medical treatment device for treating a body vessel, the radially expandable fluid delivery device having a microporous portion with a hydraulic conductivity less than a hydraulic conductivity of the body vessel.

20. A method of manufacturing a radially expandable fluid delivery device, comprising:

providing a tube of biocompatible fluoropolymer material having a microstructure of nodes interconnected by fibrils, wherein the microstructure has a predetermined porosity based on an extrusion and expansion forming process;

applying a radial expansion force to the tube to plastically deform the tube by expanding the tube beyond the tube's elastic limit to a predetermined diameter dimension; and

removing the radial expansion force;

wherein the tube is radially inelastic while sufficiently pliable to be collapsible and inflatable from a collapsed configuration to an expanded configuration upon introduction of an inflation force, such that the expanded configuration occurs upon inflation to the predetermined diameter dimension; and

wherein the microstructure includes at least one microporous portion of micro-channels and the predetermined porosity is sufficient for a fluid to inflate the fluid delivery device and permeate through the at least one microporous portion of micro-channels at a controlled rate of permeation.