INTERMITTENT CATHETERS

Abstract

The invention provides an intermittent catheter comprising a hollow polymeric tubular body comprising a base polymer and further comprising an amphiphilic additive at and/or on an outer surface of the body, wherein one or both of the base polymer and the additive are independently cross-linked and/or the base polymer and additive are cross-linked with each other.

Claims

1. An intermittent catheter comprising a hollow polymeric tubular body comprising a base polymer and further comprising an amphiphilic additive at and/or on an outer surface of the body, wherein one or both of the base polymer and the additive are independently cross-linked and/or the base polymer and additive are cross-linked with each other.

2. An intermittent catheter as claimed in claim 1, wherein the base polymer is cross-linked.

3. An intermittent catheter as claimed in claim 1, wherein the additive is cross-linked.

4. An intermittent catheter as claimed in claim 1, wherein the base polymer and the additive are cross-linked with each other.

5. An intermittent catheter as claimed in claim 1, wherein the base polymer is cross-linked at and/or on the outer surface.

6. (canceled)

7. (canceled)

8. An intermittent catheter as claimed in claim 1, wherein the additive is an amphiphilic A-B block copolymer comprising an A-block comprising a hydrophobic hydrocarbon portion and a hydrophilic B-block.

9. An intermittent catheter as claimed in claim 8, wherein the additive is an A-B block copolymer comprising an A-block comprising a hydrocarbon chain block of the formula CH.sub.3CH.sub.2(CH.sub.2CH.sub.2).sub.a where “a” is 5-25, and a hydrophilic B-block.

10. (canceled)

11. An intermittent catheter as claimed in claim 1, wherein the additive comprises poly(alkylene oxide) groups and the additive is cross-linked through non-covalent bonds between the poly(alkylene oxide) groups and a complexing agent.

12. An intermittent catheter as claimed in claim 1, wherein the additive is at and/or on at least 50% of the outer surface area of the polymeric tubular body.

13. A method of manufacturing an intermittent catheter, the method comprising the steps of: a. providing a base polymer and an amphiphilic additive; and b. forming a hollow polymeric tubular catheter body comprising the base polymer and additive wherein the method further comprises the step of independently cross-linking one or both of the base polymer and additive and/or cross-linking the base polymer and the additive with each other.

14. A method as claimed in claim 13, wherein the method comprises cross-linking the base polymer.

15. A method as claimed in claim 13, wherein the method comprises cross-linking the additive.

16. A method as claimed in claim 13, wherein the method comprises cross-linking the base polymer and the additive with each other.

17. A method as claimed in claim 13, wherein the method comprises cross-linking one or both of the base polymer and the additive independently, before cross-linking the base polymer and the additive with each other.

18. A method as claimed in claim 13, wherein the method comprises cross-linking one or both of the base polymer and the additive independently, after cross-linking the base polymer and the additive with each other.

19. A method as claimed in claim 13, wherein the method comprises cross-linking one or both of the base polymer and the additive independently and/or cross-linking the base polymer and the additive with each other during co-granulation of the base polymer with the additive.

20. A method as claimed in claim 13, wherein the method comprises the step of cross-linking one or both of the base polymer and the additive independently and/or cross-linking the base polymer and the additive with each other during and/or after extrusion or injection moulding of a mixture comprising the base polymer and the additive.

21. A method as claimed in claim 13, wherein the method comprises the step of cross-linking one or both of the base polymer and the additive independently and/or cross-linking the base polymer and the additive with each other during and/or after co-extrusion of a layer or coating of the additive on an outer surface of the base polymer.

22. (canceled)

23. (canceled)

24. A method as claimed in claim 13, wherein the additive is an amphiphilic A-B block copolymer comprising an A-block comprising a hydrophobic hydrocarbon portion and a hydrophilic B-block.

25. A method as claimed in claim 24, wherein the additive is an A-B block copolymer comprising an A-block comprising a hydrocarbon chain block of the formula CH.sub.3CH.sub.2(CH.sub.2CH.sub.2).sub.a where “a” is 5-25, and a hydrophilic B-block.

26-31. (canceled)

Description

DETAILED DESCRIPTION OF THE INVENTION

[0138] In order that the invention may be more clearly understood embodiments thereof will now be described, by way of example only:

Example 1

[0139] A first embodiment of an intermittent catheter of the invention comprises an intermittent catheter comprising a hollow polymeric tubular body comprising a base polymer formed of thermoplastic polypropylene and further comprising an amphiphilic additive of the formula CH.sub.3CH.sub.2(CH.sub.2CH.sub.2).sub.15(OCH.sub.2CH.sub.2).sub.5OH. The amphiphilic additive comprises a hydrophilic block which seeks towards the outer surface of the body due to its incompatibility with the base polymer, the outer surface becoming lubricious as a result. The lipophilic and hydrophobic block of the amphiphilic additive ensures that the hydrophilic block is secured to the base material. The amphiphilic additive is independently cross-linked through non-covalent bonds formed between the poly(ethylene oxide) groups and a urea complexing agent.

[0140] The non-cross-linked intermittent catheter may be prepared as described in US patents U.S. Pat. Nos. 10,058,638 B2 and 9,186,438 B2. The amphiphilic additive may be independently cross-linked by treating the non-cross-linked intermittent catheter with a solution of urea.

[0141] The intermittent catheter is used in the conventional manner.

[0142] The amphiphilic additive at the outer surface of the intermittent catheter body confers high lubricity to the outer surface of the intermittent catheter, making it both easier to insert and remove. The additive cross-links increase the difficulty for the additive to migrate, particularly out of the intermittent catheter. Cross-linking the additive is believed to reduce the mobility of the additive within the polymer matrix through creating an insoluble matrix of additive and/or base polymer, which in turn restricts the migration of the additive out of the catheter. This allows for the intermittent catheter to retain its lubricious surface for longer and even when the surface of the catheter is scraped or when the catheter is packaged in water or aqueous solutions.

[0143] The intermittent catheter of Example 1 conferred reduced migration of the amphiphilic additive from the surface of the catheter during both storage/transport and through use of the catheter. It also provided reduced resistance to abrasion of the additive from the surface of the catheter on contact with external bodies.

Example 2

[0144] A second embodiment of an intermittent catheter of the invention comprises an intermittent catheter comprising a hollow polymeric tubular body comprising a base polymer formed of polyethylene and further comprising an amphiphilic additive of the formula CH.sub.3CH.sub.2(CH.sub.2CH.sub.2).sub.20(OCH.sub.2CH.sub.2).sub.8OH on the outer surface of the body. The amphiphilic additive is cross-linked with the base polymer.

[0145] The non-cross-linked intermittent catheter may be prepared as described in US patents

[0146] U.S. Pat. Nos. 10,058,638 B2 and 9,186,438 B2, but without the step of adding the additive. The non-cross-linked intermittent catheter may then be treated with a mixture of the amphiphilic additive, PEGDA multifunctional monomer and Irgacure 2959 photoinitiator followed by ultraviolet irradiation. This provides cross-linking of the amphiphilic additive to the base polymer on the outer surface of the intermittent catheter.

[0147] The intermittent catheter is used in the conventional manner.

[0148] The amphiphilic additive on the outer surface of the intermittent catheter body confers high lubricity to the outer surface of the intermittent catheter, making it both easier to insert and remove. Cross-linking the additive to the base polymer increases the difficulty for the additive to migrate, particularly out of the intermittent catheter. This allows for the intermittent catheter to retain its lubricious surface for longer and even when the surface of the catheter is scraped or when the catheter is packaged in water or aqueous solutions. The intermittent catheter of Example 1 conferred reduced migration of the amphiphilic additive from the surface of the catheter during both storage/transport and through use of the catheter. It also provided reduced resistance to abrasion of the additive from the surface of the catheter on contact with external bodies.

Example 3

[0149] A third embodiment of an intermittent catheter of the invention comprises an intermittent catheter comprising a hollow polymeric tubular body comprising a base polymer formed of thermoplastic polyethylene and further comprising an amphiphilic additive of the formula CH.sub.3CH.sub.2(CH.sub.2CH.sub.2).sub.10(OCH.sub.2CH.sub.2).sub.4OH. The amphiphilic additive comprises a hydrophilic block which seeks towards the outer surface of the body due to its incompatibility with the base polymer, the outer surface becoming lubricious as a result.

[0150] The lipophilic and hydrophobic block of the amphiphilic additive ensures that the hydrophilic block is secured to the base material. The thermoplastic polyethylene base polymer comprises silane groups and the base polymer is independently cross-linked through Si—O—Si bonds between the silane groups and water.

[0151] The non-cross-linked intermittent catheter may be prepared as described in US patents U.S. Pat. Nos. 10,058,638 B2 and 9,186,438 B2, but with an added step of adding VMSI organofunctional silane and DCP peroxide to the polymer mixture during extrusion of the intermittent catheter to graft the silane to the polyethylene base material. The non-cross-linked intermittent catheter may then be treated with water in a steam chamber after extrusion. This effects independent cross-linking of the base polymer.

[0152] The intermittent catheter is used in the conventional manner.

[0153] The amphiphilic additive at the outer surface of the intermittent catheter body confers high lubricity to the outer surface of the intermittent catheter, making it both easier to insert and remove. The base polymer cross-links increase the difficulty for the additive to migrate, particularly out of the intermittent catheter. This allows for the intermittent catheter to retain its lubricious surface for longer and even when the surface of the catheter is scraped or when the catheter is packaged in water or aqueous solutions. The intermittent catheter of Example 1 conferred reduced migration of the amphiphilic additive from the surface of the catheter during both storage/transport and through use of the catheter. It also provided reduced resistance to abrasion of the additive from the surface of the catheter on contact with external bodies.

[0154] The above embodiments are described by way of example only. Many variations are possible without departing from the scope of the invention as defined in the appended claims.