Polymerized crystalline colloidal arrays

• US 6,544,800 B2
• Filed: 01/03/2001
• Issued: 04/08/2003
• Est. Priority Date: 11/06/1996
• Status: Expired due to Term

• Current Assignee: University Of Pittsburgh (University of Pittsburgh of The Commonwealth System of Higher Education)
• Original Assignee: University Of Pittsburgh (University of Pittsburgh of The Commonwealth System of Higher Education)
• Inventors: Asher, Sanford A.
• Primary Examiner(s): CEPERLEY, MARY
• Application Number:
  US09/753,592
• Publication Number:
  US 20010026946A1
• Time in Patent Office: 825 Days
• Field of Search: 436/73, 436/79, 436/518, 436/529, 436/531, 436/805, 436/811, 435/14, 359/885, 252/582
• US Class Current: 436/531
• CPC Class Codes: B01J 13/00 Colloid chemistry, e.g. the production of colloidal materials or their solutions, not otherwise provided for; Making microcapsules or microballoons
• CPC Class Codes: B01J 13/0065 containing an organic phase
• CPC Class Codes: G01J 3/18 using diffraction elements, e.g. grating gratings per se G02B
• CPC Class Codes: G01N 2021/772 Tip coated light guide
• CPC Class Codes: G01N 2021/7723 Swelling part, also for adsorption sensor, i.e. without chemical reaction
• CPC Class Codes: G01N 21/4788 Diffraction for sizing particles G01N15/0205
• CPC Class Codes: G01N 21/77 by observing the effect on a chemical indicator
• CPC Class Codes: G01N 31/222 for investigating moisture content
• CPC Class Codes: G02B 26/002 the movement or the deformation controlling the frequency of light, e.g. by Doppler effect
• CPC Class Codes: Y10S 436/805 Optical property
• CPC Class Codes: Y10S 436/811 Test for named disease, body condition or organ function
• CPC Class Codes: Y10T 436/144444 Glucose
• CPC Class Codes: Y10T 436/204998 Inorganic carbon compounds
• CPC Class Codes: Y10T 436/205831 Carbon monoxide only
• CPC Class Codes: Y10T 436/207497 Molecular oxygen
• CPC Class Codes: Y10T 436/209163 Dissolved or trace oxygen or oxygen content of a sealed environment

Abstract

Novel sensor devices composed of a crystalline colloidal array (CCA) polymerized in a hydrogel are disclosed. The hydrogels are characterized as being capable of shrinking and swelling in response to specific stimuli applied thereto. As the hydrogels shrink or swell, the lattice structure of the CCA embedded therein changes, thereby changing the wavelength of light diffracted by the CCA. Thus by monitoring the change in diffracted wavelength, the concentration of a stimulus is determined. The gels can be modified to sense numerous different stimuli. The sensor devices are specific in that they are modified to react with only one species or family of species. These sensors have various applications in areas including, for example, environmental and chemical systems, chemomechanical systems, sensor devices and medical diagnostic tools. Various methods for making and using these devices are also disclosed.

Claims

1. A method for detecting the presence of a chemical species in a solution comprising:

preparing a sensor device comprising a crystalline colloidal array of charged particles polymerized in a hydrogel that undergoes a volume change in response to said chemical species, wherein the polymerized crystalline colloidal array comprises a molecular recognition component capable of detecting the chemical species, said crystalline colloidal array having a lattice spacing that changes when said volume of said hydrogel changes, thereby causing the diffracted wavelength of the crystalline colloidal array to change;

measuring the diffracted wavelength of said crystalline colloidal array polymerized in said hydrogel;

contacting said polymerized crystalline colloidal array with said solution;

measuring the diffracted wavelength of said crystalline colloidal array following exposure to said solution; and

comparing the change in diffracted wavelength measurements to determine the presence of said chemical species, wherein said change in diffracted wavelength is caused by the contact of the chemical species with the molecular recognition component and wherein the change in diffracted wavelength correlates with the presence of the chemical species.

2. The method of claim 1, wherein the presence of said chemical species is determined by inspection of the diffracted wavelength by the polymerized crystalline colloidal array both before and after exposure to said solution, wherein a change in the wavelength diffracted by said array indicates the presence of the chemical species.

3. The method of claim 2, including employing the use of a detection device selected from the group consisting of a spectrometer or a spectrophotometer to determine said diffracted wavelength change.

4. The method of claim 2, including employing the unassisted human eye to determine said diffracted wavelength change, wherein such a change is detectable by a change in color of the sensor device.

5. The method of claim 2, wherein said sensor device preparation step includes the steps of:

a) allowing charged colloidal particles to self-assemble into a crystalline colloidal array;

b) adding a first comonomer that is a gel monomer, a crosslinking agent, a molecular recognition component and a polymerization initiator to a medium comprising said crystalline colloidal array; and

c) polymerizing the mixture of step b) to form a crystalline colloidal array embedded in a hydrogel.

6. The method of claim 5, including employing a medium that is hydrophilic.

7. The method of claim 5, including employing a gel monomer that is an ion-free gel.

8. The method of claim 5, including employing a gel monomer selected from the group consisting of acrylamide gels, purified agarose gels, N-vinylpyrolidone gels, and methacrylate gels.

9. The method of claim 8, including employing as said gel monomer N-isopropylacrylamide.

10. The method of claim 5, including employing a molecular recognition component selected from the group consisting of crown ethers, cyclodextrans and caloxarenes.

11. The method of claim 10, including employing a 4-acrylamidobenzo 18-crown-6 ether.

12. The method of claim 5, including employing a crosslinking agent selected from the group consisting of N,N′

-methylenebisacrylamide, methylenebismethacrylamide and ethyleneglycol-dimethacrylate.

13. The method of claim 12, including employing as said crosslinking agent N,N′

-methylenebisacrylamide.

14. The method of claim 5, wherein the charged particles are selected from the group consisting of colloidal polystyrene, polymethylmethacrylate, silicon dioxide, aluminum oxide, polytetrafluoroethylene and poly N-isopropylacrylamide.

15. The method of claim 5, including employing in said hydrogel a third monomer selected from the group consisting of an acrylamide or a substituted acrylamide.

16. The method of claim 1, wherein said sensor device preparation step further comprises:

a) allowing charged colloidal particles to self assemble into a crystalline colloidal array;

b) adding a gel monomer, a crosslinking agent and a polymerization initiator to a medium comprising said crystalline colloidal array;

c) polymerizing the mixture of step b) to form a crystalline colloidal array embedded in a hydrogel; and

d) adding a biomolecular recognition component to the product of step c), wherein the biomolecular recognition component is the molecular recognition component.

17. The method of claim 16, wherein said biomolecular recognition component is linked to the product of step c) by at least one linking molecule.

18. The method of claim 17, wherein said biomolecular recognition component is reacted with a first linking molecule that binds to the hydrogel or that binds to a second linking molecule that binds to the hydrogel.

19. The method of claim 18, including employing avidin as the first linking molecule that binds to the second linking molecule or to the gel.

20. The method of claim 17, including employing as said linking molecule 5-(biotinamido)pentylamine.

21. The method of claim 16, including the step of hydrolyzing the polymerized crystalline colloidal array of step c) before adding a biomolecular recognition component.

22. The method of claim 16, including employing said sensor device to detect a particular chemical species by using a biomolecular recognition component capable of recognizing the chemical species to be detected.

23. The method of claim 16, including employing a UV photoinitiator and wherein said polymerization step is effected by exposing the mixture of step b) to UV light.

24. The method of claim 16, including employing a gel monomer selected from the group consisting of acrylamide gels, purified agarose gels, N-vinylpyrolidone gels, and methacrylate gels.

25. The method of claim 24, including employing as said gel monomer N-isopropylacrylamide.

26. The method of claim 16, including employing a biomolecular recognition component selected from the group consisting of enzymes, antigens, nucleic acids, nucleic acid sequences, amino acids, amino acid sequences, peptides and antibodies.

27. The method of claim 26, wherein said biomolecular recognition component is glucose oxidase and said chemical species is dissolved oxygen.

28. The method of claim 16, including employing a crosslinking agent selected from the group consisting of N,N′

-methylenebisacrylamide, methylenebismethacrylamide and ethyleneglycol-dimethacrylate.

29. The method of claim 28, including employing as said crosslinking agent N,N′

-methylenebisacrylamide.

30. The method of claim 16, wherein the charged particles are selected from the group consisting of colloidal polystyrene, polymethylmethacrylate, silicon dioxide, aluminum oxide, polytetrafluoroethylene and poly N-isopropylacrylamide.

31. The method of claim 1, wherein said chemical species is a gas.

32. The method of claim 31 wherein said gas is selected from the group consisting of oxygen, carbon monoxide, and carbon dioxide.

33. The method of claim 32, wherein said gas is dissolved oxygen.