Multiple-sample microfluidic chip for DNA analysis

• US 20110223605A1
• Filed: 03/04/2011
• Published: 09/15/2011
• Est. Priority Date: 06/04/2009
• Status: Active Grant

• Current Assignee: Leidos Innovations Technology, Inc., Microgem NZ Limited
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Landers, James P, Scott, Orion N, Bienvenue, Joan M.
• Granted Patent: US 9,649,631 B2
• Time in Patent Office: Days
• US Class Current: 435/6.12
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/087 Multiple sequential chambers
• CPC Class Codes: B01L 2400/0421 electrophoretic flow
• CPC Class Codes: B01L 3/502753 characterised by bulk separation arrangements on lab-on-a-chip devices, e.g. for filtration or centrifugation separation in general B01D; microapparatus for analysis using electrophoresis G01N27/44791; sample preparation G01N1/28
• CPC Class Codes: B01L 7/525 with physical movement of samples between temperature zones
• CPC Class Codes: G01N 2021/4186 Phase modulation imaging
• CPC Class Codes: G01N 27/44791 Microapparatus sample containers with integrated microfluidic structures B01L3/5027
• CPC Class Codes: G01N 29/32 Arrangements for suppressing undesired influences, e.g. temperature or pressure variations , compensating for signal noise

Abstract

Aspects of the disclosure provide a microfluidic chip. The microfluidic chip includes a first domain configured for polymerase chain reaction (PCR) amplification of DNA fragments, and a second domain for electrophoretic separation. The first domain includes at least a first reaction reservoir designated for PCR amplification based on a first sample, and a second reaction reservoir designated for PCR amplification based on a second sample. The second domain includes at least a first separation unit coupled to the first reaction reservoir to received first amplified DNA fragments based on the first sample, and a second separation unit coupled to the second reaction reservoir to received second amplified DNA fragments based on the second sample. The first separation unit is configured to perform electrophoretic separation for the first amplified DNA fragments, and the second separation unit is configured to perform electrophoretic separation for the second amplified DNA fragments.

Claims

1. A microfluidic chip, comprising:

a first domain configured for polymerase chain reaction (PCR) amplification of DNA fragments, the first domain including at least a first reaction reservoir designated for PCR amplification based on a first sample, and a second reaction reservoir designated for PCR amplification based on a second sample; and

a second domain including at least a first separation unit coupled to the first reaction reservoir to received first amplified DNA fragments based on the first sample, and a second separation unit coupled to the second reaction reservoir to received second amplified DNA fragments based on the second sample, the first separation unit being configured to perform electrophoretic separation for the first amplified DNA fragments, and the second separation unit being configured to perform electrophoretic separation for the second amplified DNA fragments.

2. The microfluidic chip of claim 1, further comprising:

first inlets configured to input a first template DNA extracted from the first sample and first reagents for PCR amplification into the first reaction reservoir; and

second inlets configured to input a second template DNA extracted from the second sample and second reagents for PCR amplification into the second reaction reservoir.

3. The microfluidic chip of claim 1, wherein

the first separation unit further comprises:

a first separation channel configured to separate the first amplified DNA fragments by electrophoretic separation; and

a first injection channel configured to inject the first amplified DNA fragments into the first separation channel by electro-kinetic injection; and

the second separation unit further comprises;

a second separation channel configured to separate the second amplified DNA fragments by electrophoretic separation; and

a second injection channel configured to inject the second amplified DNA fragments into the second separation channel by electro-kinetic injection.

4. The microfluidic chip of claim 1, wherein

the first separation unit further comprises:

first electrode reservoirs configured to apply electric fields for the electro-kinetic injection and the electrophoretic separation; and

the second separation unit further comprises;

second electrode reservoirs configured to apply electric fields for the electro-kinetic injection and the electrophoretic separation.

5. The microfluidic chip of claim 4, wherein the first separation unit and the second separation unit share at least one electrode reservoir.

6. The microfluidic chip of claim 1, wherein the first domain further comprises:

a thermal coupler reservoir configured for measuring a temperature within the first domain.

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

a dilution domain configured to dilute PCR mixtures received from the first domain and prepare the PCR mixtures for electrophoretic separations in the second domain, the dilution domain including a first dilution reservoir designated for diluting a first PCR mixture received from the first reaction reservoir, and a second dilution reservoir designated for diluting a second PCR mixture received from the second reaction reservoir.

8. The microfluidic chip of claim 7, wherein the first dilution reservoir dilutes the first PCR mixture with a first dilutant according to a first ratio from 1:

5 to 1;

20, and the second dilution reservoir dilutes the second PCR mixture with a second dilutant according to a second ratio from 1;

5 to 1;

20.

9. A DNA analyzer that is configured to receive and act on the microfluidic chip of claim 1 to perform DNA analysis.

10. A cartridge, comprising:

a sample acceptor configured to respectively extract a first template DNA from a first sample and a second template DNA from a second sample; and

a microfluidic chip having

a first domain configured for polymerase chain reaction (PCR) amplification of DNA fragments, the first domain including at least a first reaction reservoir designated for PCR amplification based on the first template DNA, and a second reaction reservoir designated for PCR amplification based on the second template DNA; and

a second domain including at least a first separation unit coupled to the first reaction reservoir to received first amplified DNA fragments based on the first template DNA, and a second separation unit coupled to the second reaction reservoir to received second amplified DNA fragments based on the second template DNA, the first separation unit being configured to perform electrophoretic separation for the first amplified DNA fragments, and the second separation unit being configured to perform electrophoretic separation for the second amplified DNA fragments.

11. The cartridge of claim 10, further comprising:

a reagent carrier configured to carry reagents for the PCR amplification, and solutions for the electrophoretic separation.

12. The cartridge of claim 10, wherein

the sample acceptor is configured to extract the first template DNA or the second template DNA by at least one of a solid phase extraction, and a liquid phase enzymatic DNA isolation.

13. The cartridge of claim 10, wherein

the sample acceptor comprises a first well having a first liquid phase mixture to extract the first template DNA from the first sample and a second well having a second liquid phase mixture to extract the second template DNA from the second sample.

14. The cartridge of claim 11, wherein the microfluidic chip further comprises:

first inlets configured to input the first template DNA and first reagents for PCR amplification into the first reaction reservoir; and

second inlets configured to input the second template DNA and second reagents for PCR amplification into the second reaction reservoir.

15. The cartridge of claim 11, wherein

the first separation unit of the microfluidic chip further comprises:

a first separation channel configured to separate the first amplified DNA fragments by electrophoretic separation; and

a first injection channel used for injecting the first amplified DNA fragments into the first separation channel by electro-kinetic injection; and

the second separation unit of the microfluidic chip further comprises;

a second separation channel configured to separate the second amplified DNA fragments of the second sample by electrophoretic separation; and

a second injection channel used for injecting the second amplified DNA fragments into the second separation channel by electro-kinetic injection.

16. The cartridge of claim 15, wherein

the first separation unit further comprises:

first electrode reservoirs configured to apply electric fields for the electro-kinetic injection and the electrophoretic separation; and

the second separation unit further comprises;

second electrode reservoirs configured to apply electric fields for the electro-kinetic injection and the electrophoretic separation.

17. The cartridge of claim 16, wherein the first separation unit and the second separation unit share at least one electrode reservoir.

18. The cartridge of claim 10, wherein the microfluidic chip further comprises:

a dilution domain configured to dilute PCR mixtures received from the first domain and prepare the PCR mixtures for electrophoretic separations in the second domain, the dilution domain including a first dilution reservoir designated for diluting a first PCR mixture received from the first reaction reservoir, and a second dilution reservoir designated for diluting a second PCR mixture received from the second reaction reservoir.

19. The cartridge of claim 10, wherein the first dilution reservoir dilutes the first PCR mixture with a first dilutant according to a first ratio from 1:

5 to 1;

20, and the second dilution reservoir dilutes the second PCR mixture with a second dilutant according to a second ratio from 1;

5 to 1;

20.

20. A method for multiple-sample DNA analysis, comprising:

inducing thermal cycles in a first domain of a microfluidic chip for PCR amplification of DNA fragments, the first domain including at least a first reaction reservoir designated for PCR amplification based on a first sample, and a second reaction reservoir designated for PCR amplification based on a second sample;

inducing liquid flow to respectively move first amplified DNA fragments from the first reaction reservoir to a first separation unit in a second domain of the microfluidic chip, and second amplified DNA fragments from the second reaction reservoir to a second separation unit in the second domain of the microfluidic chip;

inducing electric fields in the first separation unit to separate the first amplified DNA fragments by size;

inducing electric fields in the second separation unit to separate the second amplified DNA fragments by size; and

detecting the separated DNA fragments.

21. The method of claim 20, further comprising:

extracting a first template DNA from the first sample; and

extracting a second template DNA from the second sample.

22. The method of claim 21, further comprising:

maintaining a temperature to enable liquid phase enzymatic DNA isolation for extracting at least one of the first template DNA and the second template DNA.

23. The method of claim 21, further comprising:

injecting first reagents and the first template DNA into the first reaction reservoir; and

injecting second reagents and the second template DNA into the second reaction reservoir.

24. The method of claim 20, wherein detecting the separated DNA fragments further comprises:

emitting a laser beam;

splitting the laser beam into a first laser beam and a second laser beam;

directing the first laser beam to a first separation channel of the first separation unit to excite a first fluorescence from first fluorescent labels attached to the first amplified DNA fragments;

directing the second laser beam to a second separation channel of the second separation unit to excite a second fluorescence from second fluorescent labels attached to the second amplified DNA fragments; and

detecting the first fluorescence and the second fluorescence.

25. The method of claim 24, wherein detecting the first fluorescence and the second fluorescence comprises:

detecting the first fluorescence by a first detector; and

detecting the second fluorescence by a second detector.

26. The method of claim 24, wherein detecting the first fluorescence and the second fluorescence comprises:

multiplexing the first fluorescence and the second fluorescence; and

detecting the multiplexed fluorescence by a detector.

27. The method of claim 20, wherein inducing liquid flow to respectively move the first amplified DNA fragments from the first reaction reservoir to the first separation unit in the second domain of the microfluidic chip, and the second amplified DNA fragments from the second reaction reservoir to the second separation unit in the second domain of the microfluidic chip, further comprises:

inducing liquid flow to move a first PCR mixture having the first amplified DNA fragments from the first reaction reservoir to a first dilution reservoir;

diluting the first PCR mixture with a first dilutant;

inducing liquid flow to move a second PCR mixture having the second amplified DNA fragments from the second reaction reservoir to a second dilution reservoir; and

diluting the second PCR mixture with a second dilutant.

28. The method of claim 27, wherein diluting the first PCR mixture with the first dilutant and diluting the second PCR mixture with the second dilutant, further comprises:

diluting the first PCR mixture with the first dilutant according to a first ratio from 1;

5 to 1;

20; and

diluting the second PCR mixture with the second dilutant according to a second ratio from 1;

5 to 1;

20.