Quantitative two-photon flow cytometry

1. A method of multi-dye analysis of particles using flow cytometer, said method comprising:

labeling particles to be detected using two or more dyes, said two or more dyes comprising a trigger dye and a reporter dye, said trigger dye is selected from carboxyfluorescein succinimidyl ester (CFSE) and fluorescein isothiocyanate (FITC), said reporter dye is DeepRed;

suspending said particles within a non-uniform flow in a capillary;

exciting a first of said particles within said capillary using a multiphoton excitation laser beam causing said two or more dyes each to fluoresce thereby producing a first output signal and a second output signal respectively;

detecting said first output signal and said second output signal;

exciting a second of said particles within said capillary using said multiphoton excitation laser beam causing said two or more dyes each to fluoresce thereby producing a third output signal and a fourth output signal respectively; and

comparing a ratio of said first output signal and said second output signal to a ratio of said third output signal and said fourth output signal to detect a desired change in said particles.

2. The method according to claim 1 wherein said first output signal has a first wavelength and said second output signal has a second wavelength.

3. The method according to claim 1 wherein said suspending said particles within said non-uniform flow in said capillary comprises creating said non-uniform flow using a pump.

4. The method according to claim 1 wherein said suspending said particles within said non-uniform flow in said capillary comprises suspending said particles within a non-uniform, pulsatile flow.

5. The method according to claim 1 wherein said suspending said particles within said non-uniform flow in said capillary comprises suspending bacteria within said non-uniform flow.

6. The method according to claim 1 wherein said suspending said particles within said non-uniform flow in said capillary comprises suspending cancer cells within said non-uniform flow.

7. The method according to claim 1 wherein said suspending said particles within said non-uniform flow in said capillary comprises suspending stem cells within said non-uniform flow.

8. The method according to claim 1 wherein said suspending said particles within said non-uniform flow in said capillary comprises suspending a virus within said non-uniform flow.

9. The method according to claim 1 wherein said suspending said particles within said non-uniform flow in said capillary comprises suspending a particle having a diameter of about 1 nanometers within said non-uniform flow.

10. The method according to claim 1 wherein said suspending said particles within said non-uniform flow is performed in vivo.

11. A method of multi-dye analysis of particles using flow cytometer, said method comprising:

labeling particles to be detected using two or more dyes, a first of said two or more dyes being selected from carboxyfluorescein succinimidyl ester (CFSE) and fluorescein isothiocyanate (FITC), a second of said two or more dyes is DeepRed;

pumping said particles through a capillary;

exposing a first of said particles within said capillary using a multiphoton excitation laser beam causing said two or more dyes to fluoresce at a first wavelength and at a second wavelength, said first wavelength being different from said second wavelength;

detecting said first wavelength and said second wavelength of said fluorescence;

exposing a second of said particles within said capillary using said multiphoton excitation laser beam causing said two or more dyes to fluoresce at a third wavelength and at a fourth wavelength, said third wavelength being different from said fourth wavelength;

detecting said third wavelength and said fourth wavelength of said fluorescence; and

comparing a ratio of said first wavelength and said second wavelength to a ratio of said third wavelength and said fourth wavelength to detect a change therebetween.

12. The method according to claim 11 wherein said pumping said particles through said capillary comprises pumping said particles through said capillary in a non-uniform flow.

13. The method according to claim 11 wherein said pumping said particles through said capillary comprises pumping a particle chosen from the group consisting essentially of bacteria, virus, cancer cell, and stem cell through said capillary.

14. The method according to claim 11 wherein said pumping said particles through said capillary comprises pumping a particle having a diameter of about 1 nanometers through said capillary.

15. The method according to claim 11 wherein said pumping said particles through said capillary is performed in vivo.

16. A method of multi-dye analysis of particle using flow cytometer, said method comprising:

labeling a particle to be detected using two or more dyes, said two or more dyes comprising a trigger dye and a reporter dye, said trigger dye is selected from carboxyfluorescein succinimidyl ester (CFSE) and fluorescein isothiocyanate (FITC), said reporter dye is DeepRed;

suspending said particle through a capillary without sheath flow;

exciting said particle within said capillary using a multiphoton excitation laser beam causing said two or more dyes to fluoresce thereby producing at least a first output signal and a second output signal;

detecting said output signals; and

determining presence of said particle in response to said output signals.

17. The method according to claim 16 wherein said suspending said particle through said capillary comprises suspending said particle chosen from the group consisting essentially of bacteria, virus, cancer cell, and stem cell through said capillary.

18. The method according to claim 16 wherein said suspending said particles through said capillary is performed in vivo.