Multiple-sample microfluidic chip for DNA analysis

• US 9,649,631 B2
• Filed: 03/04/2011
• Issued: 05/16/2017
• Est. Priority Date: 06/04/2009
• Status: Active Grant

• Current Assignee: Leidos Innovations Technology, Inc., Microgem NZ Limited
• Original Assignee: Leidos Innovations Technology, Inc.
• Inventors: Bienvenue, Joan M, Landers, James P, Scott, Orion N
• Primary Examiner(s): MUMMERT, STEPHANIE KANE
• Application Number:
  US13/064,093
• Publication Number:
  US 20110223605A1
• Time in Patent Office: 2,265 Days
• Field of Search: None
• 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 method for multiple-sample DNA analysis, comprising:

injecting a first template DNA extracted based on a first sample from a first well on a cartridge through a first inlet to a first reaction reservoir in a first domain of a microfluidic chip on the cartridge;

injecting a second template DNA extracted based on a second sample from a second well on the cartridge through a second inlet to a second reaction reservoir in the first domain of the microfluidic chip, the second well being separate from the first well;

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

inducing electric fields in the second separation unit to separate the second amplified DNA fragments by size in a second separation channel on the microfluidic chip, the second separation channel being fluidically separated from the first separation channel; and

detecting the separated DNA fragments.

2. The method of claim 1, further comprising:

extracting the first template DNA from the first sample; and

extracting the second template DNA from the second sample.

3. The method of claim 2, 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.

4. The method of claim 2, 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.

5. The method of claim 1, 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 the 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 the 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.

6. The method of claim 5, 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.

7. The method of claim 5, 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.

8. The method of claim 1, 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.

9. The method of claim 8, wherein diluting the first PCR mixture with the first dilutant and diluting the second PCR mixture with the second dilutant, further

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.

10. The method of claim 1:

wherein inducing the electric field in the second separation unit to separate the second amplified DNA fragments by size in the second separation channel on the microfluidic chip further comprises;

inducing the electric fields in the second separation unit simultaneously as in the first separation unit to simultaneously separate the second amplified DNA fragments and the first amplified DNA fragments.