Encapsulation of gases within cyclodextrins

Patent metadata

Field	Value
Publication number	US-10351634-B2
Application number	US-201314434638-A
Country	US
Kind code	B2
Filing date	Oct 10, 2013
Priority date	Oct 10, 2012
Publication date	Jul 16, 2019
Grant date	Jul 16, 2019

Abstract

An inclusion complex of an amorphous α-cyclodextrin, or derivative thereof, with encapsulated ethylene is provided by exposure of the dry solid amorphous α-cyclodextrin to ethylene gas under pressure. The inclusion complex will have applications in a number of fields including fruit ripening.

First claim

The invention claimed is:

1. An inclusion complex consisting of (i) an amorphous cyclodextrin molecule, or amorphous derivative thereof, wherein the amorphous cyclodextrin molecule defines an internal cavity and (ii) an encapsulated gaseous molecule accommodated within the internal cavity of the amorphous cyclodextrin molecule.

2. The inclusion complex of claim 1 wherein the amorphous cyclodextrin is an α-, β- or γ-cyclodextrin or an alkylated, hydroxylated or sulfonated derivative thereof.

3. The inclusion complex of claim 1 wherein the amorphous cyclodextrin is amorphous α-cyclodextrin.

4. The inclusion complex of claim 1 wherein the gaseous molecule is selected from the group consisting of methane, ethane, propane, ethylene, propylene, butylene, 1-methylcyclopropene, carbon dioxide and nitrous oxide.

5. The inclusion complex of claim 1 comprising at least 0.7 moles of ethylene per mole of α-cyclodextrin.

6. The inclusion complex of claim 1 as defined by the XRD data shown in FIG 1 .

7. A method of producing the inclusion complex of claim 1 , including the steps of:
(a) providing a solution of a cyclodextrin, or derivative thereof;
(b) actively removing solvent from the solution of cyclodextrin to form a solid amorphous cyclodextrin, or amorphous derivative thereof, powder; and
(c) exposing the solid amorphous cyclodextrin, or amorphous derivative thereof, powder to a gaseous molecule,

to thereby produce the inclusion complex.

8. The method of claim 7 wherein the cyclodextrin is an α-, β- or γ-cyclodextrin or an alkylated, hydroxylated or sulfonated derivative thereof.

9. The method of claim 7 wherein the gaseous molecule is selected from the group consisting of methane, ethane, propane, ethylene, propylene, butylene, 1-methylcyclopropene, carbon dioxide and nitrous oxide.

10. The method of claim 7 wherein the step of removing the solvent includes the step of evaporating the solvent and/or freeze drying the solution and/or spray drying the solution of cyclodextrin.

11. The method of claim 7 wherein the solution is formed using a polar, semi-polar or ionic solvent.

12. The method of claim 7 wherein the solution is an aqueous solution.

13. The method of claim 7 wherein the amorphous cyclodextrin is dry prior to exposure to the gaseous molecule.

14. The method of claim 7 wherein the amorphous cyclodextrin powder is exposed to the gaseous molecule in a closed gas tight environment at a pressure above atmospheric pressure.

15. The method of claim 7 wherein the amorphous cyclodextrin powder is exposed to the gaseous molecule at a pressure of between about 0.5MPa to about 3 MPa.

16. A method of ripening a fruit including the step of exposing the fruit to an effective amount of the inclusion complex of claim 1 .

17. The method of claim 16 wherein the step of exposing the fruit to the inclusion complex occurs while the fruit is in transit.

18. The method of claim 16 wherein the exposure occur via a controlled release device.

19. The method of claim 16 wherein the exposure of the fruit to the inclusion complex does not require solubilisation or partial dissolution of the inclusion complex to release the encapsulated gaseous molecule.

20. The method of claim 16 wherein the exposure of the fruit to the inclusion complex occurs at a temperature between about 10° C. to about 20° C.

Assignees

• Univ Queensland

Inventors

• Bhandari Bhesh
• Ho Binh Thanh

Classifications

• C08B37/0015 Primary

  Inclusion compounds, i.e. host-guest compounds, e.g. polyrotaxanes · CPC title

• A23N15/06

  Devices for other treatment of fruit, e.g. marking, maturing, polishing · CPC title

• A23B7/153

  in the form of liquids or solids · CPC title

• A23B7/144

  in the form of gases, e.g. fumigation; Compositions or apparatus therefor · CPC title

• A23B7/152

  in a controlled atmosphere comprising other gases in addition to CO2, N2, O2 or H2O {; Elimination of such other gases} · CPC title