Microwave-assisted chromatography preparation

• US 7,348,526 B2
• Filed: 08/20/2004
• Issued: 03/25/2008
• Est. Priority Date: 08/20/2004
• Status: Expired due to Fees

• Current Assignee: CEM Global LLC
• Original Assignee: CEM Global LLC
• Inventors: Thomas, James Edward, Barnhardt, E. Keller, Collins, Michael John Sr., Hargett, Wyatt Price Jr., Collins, Michael John Jr.
• Primary Examiner(s): ROBINSON, DANIEL LEON
• Application Number:
  US10/923,243
• Publication Number:
  US 20060038118A1
• Time in Patent Office: 1,313 Days
• Field of Search: 219/679, 219/601, 219/680, 219/678, 210/656, 210/657, 435/288.6, 422/21, 422/1, 95/233.9, 95/615.3, 73/232.5, 73/190.2, 73/232.2, 73/615.3
• US Class Current: 219/679
• CPC Class Codes: F26B 21/14 using gases or vapours other than air or steam , e.g. inert gases
• CPC Class Codes: F26B 3/347 Electromagnetic heating, e.g. induction heating or heating using microwave energy
• CPC Class Codes: F26B 5/048 in combination with heat developed by electro-magnetic means, e.g. microwave energy
• CPC Class Codes: F26B 9/003 Small self-contained devices, e.g. portable
• CPC Class Codes: G01N 1/44 Sample treatment involving radiation, e.g. heat
• CPC Class Codes: G01N 2030/567 coating
• CPC Class Codes: G01N 30/06 Preparation
• CPC Class Codes: H05B 6/806 for laboratory use

Abstract

An instrument and associated method are disclosed for preparing samples for column chromatography. The method includes the steps of applying microwave energy to a sample composition containing at least one solvent to encourage a chemical reaction and generate desired products, thereafter mixing an absorbent media with the sample to absorb the solvent, the media being compatible with liquid chromatography that will separate the expected products, being chemically inert to the expected products, and being added in an amount sufficient to provide a substantially dry mixture of the media and the sample, but less than an amount that overly broadens the resolution of the sample during liquid chromatography, thereafter applying microwave energy to the dry mixture of the media and the sample to thereby encourage the solvent to evaporate under the influence of the microwave energy, and thereafter adding the dry mixture of the media and the remaining sample to a liquid chromatography column and separating the components of the remaining sample for identification and purification purposes.

Claims

1. A method of preparing samples for column chromatography, comprising:

mixing a sample including reaction solvent with a solid phase chromatography medium in an amount sufficient to provide a substantially dry mixture of the media and the sample, but less than an amount that overly broadens the resolution of the sample during liquid chromatography;

applying microwave energy to the sample while concurrently providing a gas flow over and around the sample to thereby encourage the solvent to evaporate under the influence of the microwave energy and the flowing gas; and

adding the dry mixture of the media and the remaining sample to a liquid chromatography column and separating the components of the remaining sample for identification and purification purposes.

2. The chromatography preparation method according to claim 1, wherein the step of providing a gas flow comprises reducing the pressure over the sample.

3. The chromatography preparation method according to claim 1, wherein the step of applying microwave energy to the sample comprises electronic microprocessor control.

4. The chromatography preparation method according to claim 1, wherein the step of providing a gas flow over and around the sample comprises electronic microprocessor control.

5. The chromatography preparation method according to claim 1, comprising applying the microwave energy and gas flow to a sample in a sample collector.

6. The chromatography preparation method according to claim 3, comprising monitoring the temperature of the sample with a temperature sensor selected from the group consisting of infrared detectors, ultraviolet detectors, and fiber optic sensors.

7. The chromatography preparation method according to claim 6, comprising monitoring the temperature of the sample before the evaporation of solvent.

8. The chromatography preparation method according to claim 6, comprising monitoring the temperature of the sample during the evaporation of solvent.

9. The chromatography preparation method according to claim 6, comprising monitoring the temperature of the sample after the evaporation of solvent.

10. The chromatography preparation method according to claim 6, comprising moderating the application of microwaves based upon the monitored temperature.

11. The chromatography preparation method according to claim 10, comprising applying pulsed microwave energy for variable lengths of time depending on the sample volume.

12. The chromatography preparation method according to claim 1, wherein the step of applying microwave energy to the sample while concurrently providing a gas flow over and around the sample essentially dries the solvent from the chromatography media.

13. A method for microwave assisted chromatography sample preparation, comprising:

mixing a sample dissolved in reaction solvent with a solid phase chromatography medium in an amount sufficient to provide a substantially dry mixture of the media and the sample, but less than an amount that overly broadens the resolution of the sample during liquid chromatography;

applying microwave energy to the sample to evaporate solvents therein;

creating a gas flow through a vessel to evacuate the vaporized solvents;

monitoring the temperature of the media using temperature sensors; and

moderating the temperature of the sample;

while controlling the steps of applying microwave energy, moderating the temperature of the sample, and creating a gas flow through the vessel using a microprocessor; and

adding the dry mixture of the media and the remaining sample to a liquid chromatography column and separating the components of the remaining sample for identification and purification purposes.

14. The method as in claim 13, wherein the step of creating a gas flow farther comprises reducing the gas pressure in the vessel.

15. The method as in claim 13, wherein the step of applying microwave energy is programmed for variable lengths of time depending on the sample volume.

16. The method as in claim 13, comprising creating the gas flow through the vessel by activating a pump.

17. The method as in claim 16, comprising concurrently activating the pump with the application of microwave energy.

18. The method as in claim 13, wherein moderating the temperature of the sample further comprises pulsing the microwave energy via microprocessor control.

19. The method as in claim 13, comprising executing a computer program to evaporate a predetermined solvent volume.

20. A method of preparing samples for column chromatography, comprising:

mixing a sample including reaction solvent with a solid phase chromatography medium;

applying pulsed microwave energy for variable lengths of time depending on the sample volume to the sample under microprocessor control while concurrently providing a gas flow over and around the sample to thereby encourage the solvent to evaporate under the influence of the microwave energy and the flowing gas;

monitoring the temperature of the sample with a temperature sensor selected from the group consisting of infrared detectors, ultraviolet detectors, and fiber optic sensors; and

moderating the application of microwaves based upon the monitored temperature.