Bioaerosol discrimination

• US 20060237665A1
• Filed: 01/30/2006
• Published: 10/26/2006
• Est. Priority Date: 03/10/2003
• Status: Abandoned Application

• Current Assignee: Tiax, LLC
• Original Assignee: Tiax, LLC
• Inventors: Doerfler, Thomas E., Barney, William S.
• Application Number:
  US11/343,970
• Publication Number:
  US 20060237665A1
• Time in Patent Office: Days
• US Class Current: 250/458.100
• CPC Class Codes: G01N 15/1459 the analysis being performed on a sample stream
• CPC Class Codes: G01N 2001/2223 aerosol sampling devices
• CPC Class Codes: G01N 21/6408 with measurement of decay time, time resolved fluorescence

Abstract

The systems and methods of the invention utilize time-resolved techniques to deconvolve a measured response to characterize the nature of particles. The measured response is deconvolved into a scatter component and a fluorescence component. The fluorescence component is further characterized into biological and non-biological components. Probability techniques are utilized to predict whether the particles are biological or non-biological.

Claims

1. A system for classifying aerosol particles comprising:

a first detector capable of generating a first signal corresponding to a composite emission decay profile of a first emission from an aerosol particle;

a second detector capable of generating a second signal corresponding to a composite emission decay profile of a second emission from the aerosol particle; and

means for deconvolving the first and second signals into at least one discriminant vector that provides an indication of the nature of the aerosol particle.

2. A system for classifying aerosol particles comprising:

a first detector capable of generating a first signal corresponding to a first composite emission decay profile of a first emission from an aerosol particle;

a second detector capable of generating a second signal corresponding to a second composite emission decay profile of a second emission from the aerosol particle; and

a processor coupled to the first and second detectors to receive the first and second signals,

wherein the processor can determine a first scatter component and a first fluorescence component of the first composite emission decay profile and determine a second scatter component and a second fluorescence component of the second composite emission decay profile.

3. The system of claim 2, wherein the first fluorescence component comprises a first biological component and a first non-biological component and the second fluorescence component comprises a second biological component and a second non-biological component.

4. The system of claim 3, wherein the processor can determine a first scatter intensity value corresponding to the first scatter component.

5. The system of claim 4, wherein the processor can determine a first non-biological fluorescence value corresponding to the first non-biological component.

6. The system of claim 5, wherein the processor can determine a first biological fluorescence value corresponding to the first biological component.

7. The system of claim 2, further comprising a radiation source disposed to discharge electromagnetic energy to stimulate the emission from the sample.

8. The system of claim 7, wherein the radiation source comprises a first LED discharging electromagnetic energy at a first wavelength and a second LED discharging electromagnetic energy at a second wavelength.

9. A method of characterizing an aerosol particle comprising:

measuring a first composite emission decay profile of a first emission from the aerosol particle;

measuring a second composite emission decay profile of a second emission from the aerosol particle;

determining a biological fluorescence time constant of the first composite emission decay profile;

determining a biological fluorescence time constant of the second composite emission decay profile;

determining a first biological emission constant of the first composite emission decay profile; and

determining a second biological emission constant of the second composite emission decay profile.

10. The method of claim 9, further comprising stimulating the aerosol particle.

11. The method of claim 9, further comprising determining a first scatter emission constant of the first composite emission decay profile and determining a second scatter emission constant of the second composite emission decay profile.

12. The method of claim 11, further comprising determining a non-biological fluorescence time constant of the composite emission decay profile.

13. The method of claim 12, further comprising determining a non-biological emission constant of the composite emission decay profile.

14. The method of claim 13, further comprising normalizing the first scatter emission constant, the first biological emission constant, and the first non-biological emission constant relative to the first scatter emission constant to produce a first scatter component, a first biological component, and a first non-biological component.

15. The method of claim 14, further comprising mapping the first scatter component relative to the first biological component and the first non-biological component.

16. The method of claim 13, further comprising normalizing the second scatter emission constant, the second biological emission constant, and the second non-biological emission constant relative to the second scatter emission constant to produce a second scatter component, a second biological component, and a second non-biological component.

17. The method of claim 16, further comprising mapping the second scatter component relative to the second biological component and the second non-biological component.

18. The method of claim 13, further comprising determining a second biological fluorescence time constant of the first composite emission decay profile.

19. The method of claim 18, further comprising determining a second biological emission constant of the first composite emission,decay profile.

20. The method of claim 13, further comprising determining a second non-biological time constant of the first composite emission decay profile.

21. The method of claim 20, further comprising determining a second biological emission constant of the first composite emission decay profile.