Method for extracting lipids from tissue samples using high osmolality storage medium and product

• US 6,350,732 B1
• Filed: 11/17/1997
• Issued: 02/26/2002
• Est. Priority Date: 08/02/1987
• Status: Expired due to Term

• Current Assignee: Carbomedics Inc. (Snia SpA)
• Original Assignee: Carbomedics Inc. (Snia SpA)
• Inventors: Mcilroy, Brian K., Mechanic, Gerald L., Cheung, David T., Moore, Mark A.
• Primary Examiner(s): Peselev, Elli
• Application Number:
  US08/971,273
• Time in Patent Office: 1,562 Days
• Field of Search: 204/157.5, 574/21, 530/356, 530/412
• US Class Current: 514/17.2
• CPC Class Codes: A01N 1/02 Preservation of living parts
• CPC Class Codes: A01N 1/0226 Physiologically active agents, i.e. substances affecting physiological processes of cells and tissue to be preserved, e.g. anti-oxidants or nutrients
• CPC Class Codes: A61L 2430/40 Preparation and treatment of biological tissue for implantation, e.g. decellularisation, cross-linking
• CPC Class Codes: A61L 27/3687 characterised by the use of chemical agents in the treatment, e.g. specific enzymes, detergents, capping agents, crosslinkers, anticalcification agents
• CPC Class Codes: C08H 1/06 derived from horn, hoofs, hair, skin or leather

Abstract

A method extracting lipids from tissue samples, particularly collagenous tissue samples for use in preserving the tissue samples, is disclosed. The product of the method of extracting the lipids is also disclosed. Extraction is accomplished by immersing the tissue sample in a medium which is an aqueous solution of a salt and a sugar that is buffered to maintain pH and which has a high (greater than about 4500 mosm) osmolality.

Claims

1. A treatment for extracting lipids from a collagenous tissue sample comprising immersing the tissue sample in an aqueous solution of a salt and a sugar, the salt being selected from the group of salts which are capable of penetrating the sample, the sugar functioning to maintain the osmolality of the solution higher than about 4500 mosm even as the salt concentration in the solution decreases as the salt penetrates the sample.

2. The treatment of claim 1 wherein said salt is utilized in a weight to volume ratio of higher than about 11.7% and said sugar is utilized in a concentration of about 30 to about 80% (W/V).

3. The treatment of claim 1 wherein said salt is either sodium chloride or potassium chloride.

4. The treatment of claim 1 wherein said sugar is either sucrose or fructose.

5. The treatment of claim 1 additionally comprising maintaining the osmolality of the solution at higher than about 4500 mosm.

6. The treatment of claim 1 wherein said salt is a halide salt.

7. A tissue sample having at least a 65% lower lipid content relative to fresh tissue samples produced by the method of claim 1.

8. A method for extracting lipids from a collagenous tissue sample for the purpose of preserving the sample comprising the steps of immersing a collagenous tissue sample in an aqueous medium and maintaining the osmolality of the medium in which the sample is immersed higher than about 4500 mosm, the storage medium comprising water, about 30 to about 80% (W:

V) sucrose, and a halide salt in a concentration of higher than about 11.7% (W;

V).

9. The method of claim 8 wherein said halide salt is either sodium chloride or potassium chloride.

10. The method of claim 9 wherein said medium additionally comprises a buffer.

11. A tissue sample having at least a 65% lower lipid content than fresh tissue samples produced by the method of claim 8.

12. A product obtained by immersing a collagenous tissue sample in an aqueous medium comprising water, sucrose, and a halide salt and maintaining the osmolality of the medium at higher than about 4500 mosm and characterized by the properties of having a lipid content at least 65% lower than fresh tissue samples and a lower bioburden than fresh tissue samples.

13. The product of claim 12 wherein the medium comprises about 30 to about 80% (W:

V) sucrose and a halide salt in a concentration of higher than about 11.7% (W;

V).

14. The product of claim 13 wherein the medium additionally comprises a buffer.