Microfluidic cartridge and method of making same

1. A method of isolating a plurality of polynucleotide-containing samples on a microfluidic cartridge, the method comprising:

introducing a first polynucleotide-containing sample into a first reaction chamber via a first inlet, the first inlet in fluid communication with the first reaction chamber;

introducing a second polynucleotide-containing sample into a second reaction chamber via a second inlet, the second inlet in fluid communication with the second reaction chamber, wherein the first polynucleotide-containing sample is different than the second polynucleotide-containing sample;

isolating the first polynucleotide-containing sample within the first reaction chamber, wherein a first set of microfluidic valves is closed;

independent of isolating the first polynucleotide-containing sample, isolating the second polynucleotide-containing sample within the second reaction chamber, wherein a second set of valves is closed; and

applying a minimum contact pressure of at least 1 psi over the microfluidic cartridge to contact the microfluidic cartridge to a heater of an instrument to assist in achieving better thermal contact between the heater of the instrument and heat-receivable parts of the microfluidic cartridge.

2. The method of claim 1 , wherein applying the minimum contact pressure comprises contacting a laminate on a lower surface of the microfluidic cartridge with the heater of the instrument.

3. The method claim 1 , further comprising amplifying one or more polynucleotides in the first reaction chamber independently of amplifying one or more polynucleotides in the second reaction chamber.

4. The method claim 3 , further comprising detecting amplified polynucleotides.

5. The method claim 4 , wherein detecting amplified polynucleotides comprises use of an optical detector comprising a light source that selectively emits light in an absorption band of a fluorescent dye and a light detector that selectively detects light in an emission band of the fluorescent dye, wherein the fluorescent dye corresponds to a fluorescent polynucleotide probe or a fragment thereof.

6. The method claim 1 , wherein the heater of the instrument is configured to heat the first reaction chamber.

7. The method claim 1 , further comprising selectively receiving the microfluidic cartridge in a bay.

8. The method claim 1 , further comprising fitting a registration member of the microfluidic cartridge into a complementary feature.

9. The method of claim 1 , wherein the heater of the instrument is selected from a resistive heater, a radiator, a fluidic heat exchanger, and a Peltier device.

10. A method of isolating a plurality of polynucleotide-containing samples on a microfluidic cartridge, the method comprising:

providing the microfluidic cartridge comprising a plurality of sample lanes, wherein each of the plurality of sample lanes comprises a microfluidic network having, in fluid communication with one another:

a first valve;

a second valve;

a reaction chamber,

a first channel leading, via the first valve, to the reaction chamber; and

a second channel leading, via the second valve, from the reaction chamber;

introducing a first polynucleotide-containing sample into a first reaction chamber in a first microfluidic network and introducing a second polynucleotide-containing sample into a second reaction chamber in a second microfluidic network, wherein the first polynucleotide-containing sample is different than the second polynucleotide-containing sample;

isolating the first polynucleotide-containing sample to prevent movement into or out of the first reaction chamber, wherein the first valve and the second valve of the first microfluidic network are closed when the first polynucleotide-containing sample is isolated;

isolating the second polynucleotide-containing sample to prevent movement into or out of the second reaction chamber, wherein the first valve and the second valve of the second microfluidic network are closed when the second polynucleotide-containing sample is isolated; and

applying a contact pressure of at least 1 psi to the microfluidic cartridge to thermally couple at least one heat source to one or more distinct locations on the microfluidic cartridge.

11. The method claim 10 , wherein the contact pressure is applied to the microfluidic cartridge using a force member.

12. The method of claim 10 , further comprising amplifying one or more polynucleotides in the first reaction chamber independently of amplifying one or more polynucleotides in the second reaction chamber.

13. The method of claim 10 , wherein isolating the first polynucleotide-containing sample and isolating the second polynucleotide-containing sample comprises closing the first valve in the first microfluidic network independent of closing the first valve in the second microfluidic network.

14. The method claim 10 , further comprising detecting amplified nucleotides with an optical detector comprising a light source that selectively emits light in an absorption band of a fluorescent dye and a light detector that selectively detects light in an emission band of the fluorescent dye, wherein the fluorescent dye corresponds to a fluorescent polynucleotide probe or a fragment thereof.

15. The method of claim 10 , wherein the at least one heat source is disposed underneath the microfluidic cartridge and a detector is disposed over the microfluidic cartridge.

16. A method of isolating a plurality of polynucleotide-containing samples on a microfluidic cartridge, the method comprising:

providing the microfluidic cartridge comprising a plurality of sample lanes, wherein each of the plurality of sample lanes comprises a microfluidic network having, in fluid communication with one another:

a first valve;

a second valve;

a reaction chamber,

a first channel leading, via the first valve, to the reaction chamber; and

a second channel leading, via the second valve, from the reaction chamber;

introducing a first polynucleotide-containing sample into a first reaction chamber in a first microfluidic network and introducing a second polynucleotide-containing sample into a second reaction chamber in a second microfluidic network, wherein the first polynucleotide-containing sample is different than the second polynucleotide-containing sample;

isolating the first polynucleotide-containing sample in the first reaction chamber;

isolating the second polynucleotide-containing sample in the second reaction chamber,

amplifying the first polynucleotide-containing sample in the first reaction chamber;

amplifying the second polynucleotide-containing sample in the second reaction chamber;

applying contact force of at least 1 psi by a contact force member to press the microfluidic cartridge over heaters so that the first reaction chamber and the second reaction chamber of the microfluidic cartridge make thermal contact with the heaters for amplification.

17. The method claim 16 , further comprising detecting amplified nucleotides with an optical detector comprising a light source that selectively emits light in an absorption band of a fluorescent dye and a light detector that selectively detects light in an emission band of the fluorescent dye, wherein the fluorescent dye corresponds to a fluorescent polynucleotide probe or a fragment thereof.

18. The method of claim 16 , further comprising amplifying one or more polynucleotides in the first reaction chamber independently of amplifying one or more polynucleotides in the second reaction chamber.