Cryogenic, elastomeric closure for cryogen containers

• US 8,092,878 B2
• Filed: 04/17/2007
• Issued: 01/10/2012
• Est. Priority Date: 04/17/2006
• Status: Active Grant

• Current Assignee: West Pharmaceutical Services Incorporated
• Original Assignee: West Pharmaceutical Services Incorporated
• Inventors: Miller, Timothy M., Drummond, John N., Duriez, Douglas R.
• Primary Examiner(s): Dye, Rena
• Assistant Examiner(s): YAGER, JAMES C
• Application Number:
  US11/787,467
• Publication Number:
  US 20070246468A1
• Time in Patent Office: 1,729 Days
• Field of Search: 428/35.7, 428/36.8, 215/247, 215/355, 215/296
• US Class Current: 428/36.8
• CPC Class Codes: A01N 1/02 Preservation of living parts
• CPC Class Codes: A01N 1/0257 Stationary or portable vessels generating cryogenic temperatures
• CPC Class Codes: A01N 1/0268 Carriers for immersion in cryogenic fluid, both for slow-freezing and vitrification, e.g. open or closed "straws" for embryos, oocytes or semen
• CPC Class Codes: B01L 2300/12 Specific details about materials
• CPC Class Codes: B01L 2300/1894 Cooling means; Cryo cooling
• CPC Class Codes: B01L 3/50825 Closing or opening means, corks, bungs closures for containers B65D; means for removing stoppers B67B7/02
• CPC Class Codes: B65D 2539/008 with coatings or coverings
• CPC Class Codes: B65D 39/0076 Plastic closures other than those covered by groups B65D39/0058 - B65D39/007
• CPC Class Codes: B65D 51/002 Closures to be pierced by an extracting-device for the contents and fixed on the container by separate retaining means
• CPC Class Codes: F16L 55/1141 the plug being made of elastic material
• CPC Class Codes: Y10T 428/1352 Polymer or resin containing [i.e., natural or synthetic]
• CPC Class Codes: Y10T 428/1386 Natural or synthetic rubber or rubber-like compound containing

Abstract

A multi-material, cryogenic, elastomeric closure is provided for sealing a container for samples of cryophilic biological materials, pharmaceuticals or the like. The closure includes at least one cryophilic elastomer having a glass transition temperature (T_g) below the cryogenic temperature to which the sample is to be subjected and at least one non-cryophilic elastomer having a T_g above the cryogenic temperature. The cryophilic and non-cryophilic elastomers are present in such a manner as to maintain a complete seal of the container opening at the cryogenic temperature.

Claims

1. A container assembly comprising:

a container; and

a multi-material, elastomeric, cryogenic plug or plunger for the container, wherein the cryogenic plug or plunger includes;

a base of cryophilic elastomer forming a core having at one end a first peripheral sealing surface engaging an inner wall of the container and a sidewall at a second end of the core,

a cover of non-cryophilic elastomer molded over the second end of the core, the cover having at least one second peripheral sealing surface for sealingly engaging the inner wall of the container and wherein the second peripheral sealing surface is positioned between the inner wall of the container and the core,

the non-cryophilic elastomer having a glass transition temperature (Tg) above about −

80 degrees Celsius, and

the cryophilic elastomer having a glass transition temperature (Tg) below about −

80 degrees Celsius.

2. The container assembly according to claim 1, wherein the cover is laminated to the base.

3. The container assembly according to claim 1, wherein the cover is mechanically interlocked with the base.

4. The container assembly according to claim 1, wherein the cover is co-molded with the base.

5. The container assembly according to claim 1, further comprising a barrier film surrounding portions of at least one of the base and cover exposed to an interior of the container and a sample.

6. The container assembly according to claim 1, wherein the cryophilic elastomer is at least one selected from the group consisting of polybutadienes, silicones, fluorosilicones, nitrites, and EPDM elastomers.

7. The container assembly according to claim 1, wherein the non-cryophilic elastomer is at least one selected from the group consisting of natural rubbers, butyl rubbers, isoprene rubbers, and fluorocarbon polymers.

8. The container assembly according to claim 1, wherein the container contains a sample to be subjected to a cryogenic temperature comprising a cryophilic material selected from the group consisting of biological materials, pharmaceuticals, nutritional supplements, and other nutritional products.

9. The container assembly according to claim 1, wherein the first and second peripheral sealing surfaces comprise annular ribs.

10. The container assembly according to claim 1, wherein the non-cryophilic elastomer comprises a pharmaceutical-grade halobutyl-based polymer formulation cured with a sulphur-based cure system and the cryophilic elastomer comprises a polybutadiene-based polymer formulation cured with a sulphur-based cure system, such that the two elastomers, when molded together to form the closure, form two distinct layers forming an essentially continuous article.