Devices and methods for thermally-mediated chemical reactions

1. A microfluidic array comprising:

a platen comprising a two-dimensional array of openings configured to contain a plurality of samples, the plurality of openings disposed along rows;

a plurality of pairs of electrically conductive forgers, each pair of fingers providing electrical current through a single row in the array.

2. The microfluidic array of claim 1 , wherein the rows are disposed along a respective lines that are substantially parallel to one another.

3. The microfluidic array of claim 1 , further comprising:

one or more slots, each slot separating two of the plurality of rows.

4. The microfluidic array of claim 1 , wherein the platen is formed from a conductive material selected from the group consisting of: copper, gold, silver, nickel, iron, titanium, steel, and stainless steel.

5. The microfluidic array of claim 1 , further comprising a plurality of through-holes extending from respective ones of the plurality of openings.

6. The microfluidic array of claim 1 , further comprising a through-holes having a hydrophilic interior.

7. The microfluidic array of claim 1 , further comprising:

two outer layers of hydrophobic material coupled to a top and a bottom surface of the plurality of the rows.

8. The microfluidic array of claim 1 , further comprising a plurality of through-holes, each of the plurality of through-holes has a volume less than 100 nanoliters.

9. A container for thermal cycling a plurality of samples in a microfluidic array comprising a two-dimensional array of openings configured to contain the plurality of samples, the plurality of openings disposed along rows, the container comprising:

a plurality of walls defining an interior volume; and

a plurality of pairs of electrically conductive fingers, each pair of fingers providing electrical current through a single row in the array.

10. The container of claim 9 , further comprising:

a pair of electrically-conductive contacts located on an exterior surface of the container, the contacts in communication with the fingers.

11. The container of claim 9 , wherein the fingers are configured to contact the microfluidic array at a first and a second end of each of the plurality of rows.

12. The container of claim 9 , wherein at least one of the plurality of walls is optically transparent.

13. The container of claim 9 , wherein the plurality of fingers are comprised of a metal.

14. A method for thermal cycling a plurality of samples, the method comprising:

providing a microfluidic array including a platen comprising a two-dimensional array of openings configured to contain the plurality of samples, the plurality of openings disposed along rows

loading the plurality of samples into the plurality of openings;

placing the microfluidic array in a container, the container including a plurality of pairs of electrically conductive fingers;

applying a flow of electrical current across the plurality of rows such that each pair of fingers provides electrical current through a single row; and

terminating the flow of electrical current to allow the samples to cool.

15. The method of claim 14 , further comprising:

placing the container in contact with a heat sink.

16. The method of claim 15 , wherein the heat sink is a fluid bath.

17. The method of claim 16 , wherein the fluid bath is chilled.

18. The method of claim 15 , wherein the heat sink is a Peltier element.

19. The method of claim 14 , further comprising:

imaging the array of openings.

20. The microfluidic array of claim 1 , wherein each pair of fingers is disposed at opposite ends per row.