Strobe desorption method for high boiling point materials

• US 20050235739A1
• Filed: 03/14/2005
• Published: 10/27/2005
• Est. Priority Date: 11/21/2002
• Status: Active Grant

• Current Assignee: ADA Technologies, Inc.
• Original Assignee: ADA Technologies, Inc.
• Inventors: Barringer, Anthony Rene, Lovell, John Stanley, French, Patrick D.
• Granted Patent: US 7,299,679 B2
• Time in Patent Office: Days
• US Class Current: 73/53.10
• CPC Class Codes: F41H 11/134 Chemical systems, e.g. with detection by vapour analysis
• CPC Class Codes: G01N 1/2202 involving separation of sample components during sampling
• CPC Class Codes: G01N 1/2294 Sampling soil gases or the like
• CPC Class Codes: G01N 1/24 Suction devices G01N1/22 - G01N1/2294 take precedence
• CPC Class Codes: G01N 1/44 Sample treatment involving radiation, e.g. heat
• CPC Class Codes: G01N 2001/2223 aerosol sampling devices
• CPC Class Codes: G01N 2001/2276 Personal monitors
• CPC Class Codes: G01N 2001/4027 evaporation leaving a concentrated sample
• CPC Class Codes: Y10T 436/24 Nuclear magnetic resonance, electron spin resonance or other spin effects or mass spectrometry

Abstract

The invention is directed to a system and method for detecting substances, such as high boiling and low vapor pressure materials, using high energy radiation imparted by a suitable radiation source, such as a strobe or laser over a short time period.

Claims

1. A method for detecting a high boiling point and/or a low vapor pressure material, comprising:

directing radiation from a radiation source onto a surface potentially comprising a high boiling point and/or vapor pressure material, wherein, during a time interval of no more than about 1/100^th seconds, the directed radiation has a cumulative energy of at least about 1,200 Joules;

collecting an airborne sample at and/or near the surface; and

detecting whether or not the high boiling point and/or low vapor pressure material is present in the collected sample.

2. The method of claim 1, wherein the cumulative energy is at least about 2,400 Joules.

3. The method of claim 1, wherein the cumulative energy ranges from about 1,200 to about 4,800 Joules.

4. The method of claim 1, wherein the time interval is no more than about 1/1000^th seconds.

5. The method of claim 1, wherein the radiation source is at least one of a strobe and a laser.

6. The method of claim 1, wherein the high boiling point and/or low vapor pressure material is at least one of an explosive, an explosive related compound, a chemical warfare agent, a drug, a toxic industrial compound, and derivatives thereof.

7. The method of claim 1, wherein the material has a boiling point of at least about 150°

C.

8. The method of claim 1, wherein the material has a vapor pressure under ambient temperature and pressure of no more than about 2×

10<sup>−

3</sup> mm Hg.

9. The method of claim 1, wherein the material has a vapor pressure under standard temperature and pressure of no more than about 2×

10<sup>−

3</sup> Hg.

10. The method of claim 1, further comprising before the directing step:

applying a volatilizing agent to the surface.

11. The method of claim 10, wherein the volatilizing agent is at least one of water, a volatile organic solvent, and mixtures thereof

12. The method of claim 1, wherein the directing step is repeated at a frequency of at least about 0.5 Hz.

13. The method of claim 1, wherein the radiation source has an outputted energy profile and wherein a peak of the profile is located in a radiation absorption band of the material.

14. The method of claim 10, wherein the radiation source has an outputted energy profile and wherein a peak of the profile is located in a radiation absorption band of the volatilizing agent.

15. The method of claim 1, wherein the collecting step comprises the substep:

maintaining a negative pressure in the vicinity of the surface.

16. The method of claim 1, wherein the detecting step comprises the substep of:

transporting the collected sample through a heated conduit to a detector.

17. The method of claim 16, wherein the temperature of the heated conduit is at least the condensation temperature of the material.

18. The method of claim 16, wherein the temperature of the heated conduit ranges from about 100 to about 250°

C.

19. The method of claim 16, wherein the heated conduit comprises a glass and/or ceramic surface adjacent the transported sample.

20. The method of claim 19, wherein the heated conduit comprises a silanizing agent.

21-75. -75. (canceled)