Nanoreactors as thermal history indicators

Patent metadata

Field	Value
Publication number	US-2016356749-A1
Application number	US-201615176550-A
Country	US
Kind code	A1
Filing date	Jun 8, 2016
Priority date	Jun 8, 2015
Publication date	Dec 8, 2016
Grant date	—

Abstract

Nanoreactors comprising a metal precursor in a carrier are provided as well as methods of initiating, methods of preparing, and methods of using nanoreactors. In some embodiments, upon exposure to heat, the metal precursor forms nanoparticles that can be detected, e.g., by detecting a color change in the nanoreactor and/or by detecting the number and/or size and/or size distribution and/or shape of the nanoparticles. The nanoreactors can be used, in some embodiments, as time-temperature indicators for perishable goods.

First claim

1 . A nanoreactor comprising a metal precursor and chitosan, wherein the concentration of said metal precursor is between 0.2 mM and 3 mM and the concentration of said chitosan is between 0.0006 g/mL and 0.004 g/mL.

2 . The nanoreactor of claim 1 , wherein said nanoreactor was prepared by incubation at a temperature between 70° C. and 95° C. for between 1 and 60 minutes and then cooled to a temperature between −100° C. and 25° C.

3 . The nanoreactor of any one of claim 1 , wherein the concentration of said chitosan is between 0.0006 g/mL and 0.004 g/mL.

4 . (canceled)

5 . The nanoreactor of any one of claim 1 , wherein the concentration of said metal precursor is between 0.5 mM and 2 mM.

6 . (canceled)

7 . (canceled)

8 . The nanoreactor of any one of claim 1 , wherein said metal precursor is gold precursor.

9 . A nanoreactor comprising a metal precursor and alginic acid, wherein the concentration of said alginic acid is between 0.001 g/mL and 0.1 g/mL and the concentration of said metal precursor is between 0.2 mM and 3 mM.

10 . The nanoreactor of claim 9 , further comprising a divalent ion.

11 . The nanoreactor of any one of claim 9 , wherein said nanoreactor was prepared by incubation at a temperature between 70° C. and 95° C. for between 1 and 60 minutes and then cooled to a temperature between −100° C. and 25° C.

12 . The nanoreactor of any one of claim 9 , wherein the concentration of said alginic acid is between 0.005 g/mL and 0.015 g/mL.

13 . (canceled)

14 . The nanoreactor of any one of claim 9 , wherein the concentration of said metal precursor is between 0.5 mM and 2 mM.

15 . (canceled)

16 . (canceled)

17 . The nanoreactor of any one of claim 9 , wherein said metal precursor is gold precursor.

18 . A nanoreactor comprising a first metal precursor, a second metal precursor and carrier, wherein the concentration of said first metal precursor is between 0.01 mM and 100 mM, the concentration of said second metal precursor is between 0.001 mM and 500 mM, and the concentration of said carrier is between 0.0005 g/mL and 0.1 g/mL.

19 . The nanoreactor of claim 18 , wherein said first metal precursor is silver precursor and said second metal precursor is gold precursor.

20 . The nanoreactor of claim 19 , wherein the concentration of said gold precursor is between 0.1 mM and 10 mM.

21 . (canceled)

22 . (canceled)

23 . (canceled)

24 . (canceled)

25 . (canceled)

26 . A thermal history indicator comprising the nanoreactor of claim 1 in a container.

27 . A thermal history indicator kit comprising a metal precursor component and a carrier component, wherein said metal precursor component and said carrier component are located in separate compartments in said kit, and wherein said metal precursor component and said carrier component could be mixed so as to produce the nanoreactors in claim 1 .

28 . A method of preparing a nanoreactor comprising preparing the nanoreactor in claim 1 , heating said nanoreactor to between 70° C. and 95° C. for between 1 and 60 minutes, and cooling said nanoreactor to 30° C. or below.

29 . A method of determining the thermal history of a nanoreactor comprising detecting at least one characteristic of said nanoreactor and based on said characteristic determining whether said nanoreactor was exposed to an undesired temperature for a time period, wherein said nanoreactor was placed at a storage temperature for a time regime, and wherein said nanoreactor is the nanoreactor in claim 1 .

30 . A method of detecting exposure of a perishable good to an undesired temperature comprising exposing said perishable good to a storage temperature for a time regime wherein said perishable good is packaged in association with a nanoreactor of claim 1 , detecting at least one characteristic of said nanoreactor, and based on said characteristic determining whether said perishable good was exposed to an undesired temperature for a time period during storage.

31 . (canceled)

32 . (canceled)

33 . (canceled)

34 . (canceled)

35 . (canceled)

36 . (canceled)

37 . (canceled)

38 . (canceled)

39 . A method of determining the thermal history of a nanoreactor comprising detecting at least one characteristic of said nanoreactor and based on said characteristic determining whether said nanoreactor was exposed to an undesired temperature for a time period, wherein said nanoreactor was placed at a storage temperature for a time regime, wherein said nanoreactor comprises gold precursor present at a concentration between 0.1 mM and 5 mM, gelatin present at a concentration between 0.005 g/mL and 0.03 g/mL, and water, wherein said nanoreactor was prepared by incubation at a temperature between 70° C. and 95° C. for between 1 and 60 minutes, and wherein said time regime is more than 45 days.

40 . (canceled)

41 . (canceled)

42 . (canceled)

43 . (canceled)

44 . (canceled)

45 . (canceled)

46 . (canceled)

47 . (canceled)

Assignees

• Wisconsin Alumni Res Found

Inventors

• Gunasekaran Sundaram
• Wang Yi-Cheng

Classifications

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• G01N33/02 Primary

  Food · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• G01N25/00

  Investigating or analyzing materials by the use of thermal means (G01N3/00 - G01N23/00 take precedence) · CPC title

• G01N31/229 Primary

  for investigating time/temperature history · CPC title