Sample pre-concentration tubes with sol-gel surface coatings and/or sol-gel monolithic beds

• US 20060113231A1
• Filed: 10/11/2005
• Published: 06/01/2006
• Est. Priority Date: 10/23/2000
• Status: Abandoned Application

• Current Assignee: University of South Florida (State University System of Florida)
• Original Assignee: University of South Florida (State University System of Florida)
• Inventors: Malik, Abdul
• Application Number:
  US11/247,445
• Publication Number:
  US 20060113231A1
• Time in Patent Office: Days
• US Class Current: 210/198.200
• CPC Class Codes: B01J 20/103 comprising silica
• CPC Class Codes: B01J 20/28042 Shaped bodies; Monolithic structures
• CPC Class Codes: B01J 2220/64 In a syringe, pipette, e.g. tip or in a tube, e.g. test-tube or u-shape tube
• CPC Class Codes: G01N 1/40 Concentrating samples
• CPC Class Codes: G01N 1/405 by adsorption or absorption
• CPC Class Codes: G01N 2030/009 Extraction

Abstract

A method of pre-concentrating trace analytes is accomplished by extracting polar and non-polar analytes through a sol-gel coating. The sol-gel coating is either disposed on the inner surface of a capillary tube or disposed within the tube as a monolithic bed.

Claims

1. A microextraction device comprising:

a) a hollow capillary, and

b) at least one sol-gel extraction medium within said hollow capillary for trapping at least one target analyte, said sol-gel extraction medium chemically bound to the inner surface of said hollow capillary to form a sol-gel extraction medium-loaded capillary.

2. The microextraction device according to claim 1, wherein said sol-gel extraction medium comprises:

a) a porous sol-gel monolithic bed, said monolithic bed having a thickness equal to an internal diameter of said hollow capillary;

or

b) a sol-gel coating.

3. The microextraction device according to claim 1, wherein an organic component of said sol-gel is selected from the group consisting of sol-gel-active forms and/or derivatives of poly(ethylene glycol), poly(methylphenylsiloxane), poly(dimethyldiphenylsiloxane), poly(dimethylsiloxane), and poly(methylcyanopropylsiloxane).

4. The microextraction device according to claim 1, wherein an organic component of said sol-gel is selected from the group consisting of sol-gel-active forms and/or derivatives of octadecylsilane, octylsilane, crown ethers, cyclodextrins, calixarenes, dendrimers, poly(styrene), poly(styrene-divinylbenzene), poly(acrylate), and molecularly imprinted polymers.

5. The microextraction device according to claim 1, wherein said hollow capillary provides an internal diameter of at least 250 μ

m.

6. The microextraction device according to claim 1, wherein said device provides at least parts per trillion (ppt) level detection sensitivities.

7. The microextraction device according to claim 1, wherein said sol-gel extraction medium comprises

, wherein m=An integer ≧

0;

n=An integer ≧

0

x=An integer ≧

0;

y=An integer ≧

0;

and m, n, x, and y are not simultaneously zero.

8. The microextraction device according to claim 1, wherein the capillary is hydrothermally treated.

9. The microextraction device according to claim 1, wherein the sol-gel extraction medium comprises a plurality of zirconia elements.

21. An apparatus useful for preconcentrating and analyzing target analytes in a sample, wherein said apparatus comprises a microextraction device according to claim 1 in hyphenation with a gas chromatographic column or a high-performance liquid chromatographic column.

10. A microextraction device prepared by the method comprising:

a) processing a hollow capillary by hydrothermal treatment, said hollow capillary including an inner surface; and

b) filling the capillary with a sol-gel extraction medium, wherein the sol-gel extraction medium is chemically bound to the inner surface of the hollow capillary to form a sol-gel extraction medium-loaded capillary;

or

c) processing a hollow capillary by hydrothermal treatment, said hollow capillary including an inner surface; and

d) filling the capillary with a sol-gel extraction medium, wherein the sol-gel extraction medium is chemically bound to the inner surface of the hollow capillary to form a sol-gel extraction medium-loaded capillary; and

e) preconditioning said sol-gel extraction medium.

11. The device according to claim 10, wherein said preconditioning step comprises heating and purging an inert gas over said sol-gel extraction medium.

12. The device according to claim 10, wherein said sol-gel extraction medium comprises:

a) a porous sol-gel monolithic bed having a thickness equal to an inner diameter of said hollow capillary;

or

b) a sol-gel coating.

13. The device according to claim 10, wherein an organic component of said sol-gel is selected from the group consisting of sol-gel active forms and/or derivatives of poly(ethylene glycol), poly(methylphenylsiloxane), poly(dimethyldiphenylsiloxane) poly(dimethylsiloxane), and poly(methylcyanopropylsiloxane).

14. The device according to claim 10, wherein an organic component of said sol-gel is selected from the group consisting of sol-gel active forms and/or derivatives of octadecylsilane, octylsilane, crown ethers, cyclodextrins, calixarenes, dendrimers, poly(styrene), poly(styrene-divinylbenzene), poly(acrylate), and molecularly imprinted polymers.

15. The device according to claim 10, wherein said sol-gel extraction medium comprises a plurality of zirconia elements.

16. The device according to claim 10, wherein said sol-gel extraction medium is prepared from a sol solution comprising a transition metal alkoxide other than a silica alkoxide, a sol-gel organic component, a chelating reagent, and at least one deactivation reagent in a solvent.

17. The device according to claim 16, wherein the transition metal alkoxide is selected from the group consisting of zirconium isopropoxide, zirconium tetrapropoxide, and zirconium (IV) butoxide.

18. The device according to claim 16, wherein the sol-gel organic precursor is selected from the group consisting of polydimethylsiloxane (PDMS), polymethylphenylsiloxane (PMPS), silanol-terminated polydimethyldiphenylsiloxane (PDMDPS), and poly(methylcyanopropylsiloxane).

19. The device according to claim 16, wherein the chelating reagent is selected from the group consisting of acetic acid, valeric acid, β

-diketone, triethanolamine, and 1,5-diaminopentane.

20. The device according to claim 16, wherein the at least one deactivating reagent comprises a first deactivation reagent and a second deactivation reagent, wherein the first deactivation reagent is poly(methylhydrosiloxane), and the second deactivation reagent is 1,1,1,3,3,3-hexamethyldisilazane.