Methods and compositions related to continuous flow thermal gradient PCR

1. A method of amplifying a nucleic acid, the method comprising the steps of:

a) forming a steady state temperature gradient on a microchip comprising microchannels and a heater or heaters,

wherein the microchannel has a heating portion and a cooling portion,

wherein each portion of the microchannel has a width,

wherein the width of the heating portion is wider than the width of the cooling portion, and

wherein the heater or heaters are located adjacent to the transition from the heating portion to the cooling portion; and

b) exposing a nucleic acid to the temperature gradient in a manner conducive for amplification; thereby amplifying a nucleic acid.

2. The method of claim 1 , wherein the microchannel is in a serpentine pattern.

3. The method of claim 1 , wherein the nucleic acid is amplified multiple times.

4. The method of claim 1 , further comprising detecting nucleic acid amplification using fluorescent monitoring.

5. The method of claim 4 , wherein the nucleic acid is detected by exposing the nucleic acid to a dye, then detecting interaction of the dye and the nucleic acid.

6. The method of claim 5 , wherein the dye is fluorescent.

7. The method of claim 5 , wherein the dye is intercalating.

8. The method of claim 4 , wherein each cycle of nucleic acid replication can be detected.

9. The method of claim 4 , wherein amplification can be detected with a single photograph.

10. The method of claim 8 further comprising the step of measuring the amount of fluorescence produced by the dye after each extension.

11. The method of claim 10 , wherein amplification is detected by monitoring the channel-wise growth in fluorescence and wherein the melting behavior of the amplicon is detected during each denaturing process.

12. The method of claim 11 , further comprising the step of providing the information in real time.

13. The method of claim 4 wherein the nucleic acid is pumped into the microchannel.

14. The method of claim 13 wherein the nucleic acid is pumped into the microchannel using continuous flow.

15. The method of claim 4 , wherein detecting nucleic acid further comprises determining information related to the denaturing or melting of the double stranded nucleic acid.

16. The method of claim 5 , wherein the dye is at least one of SYBR Green, LC Green, and LC Green Plus.

17. The method of claim 11 , wherein a melting curve analysis is conducted on the nucleic acid.

18. The method of claim 4 , wherein more than one nucleic acid sample is amplified at a time.

19. The method of claim 18 , wherein the nucleic acid samples differ in sequence.

20. The method of claim 19 , wherein an analysis of the spatial fluorescence and temperature distribution can distinguish between the multiple samples of nucleic acids.