Microfluidic methods, devices and systems for in situ material concentration

• US 20030057092A1
• Filed: 07/26/2002
• Published: 03/27/2003
• Est. Priority Date: 10/31/2000
• Status: Abandoned Application

• Current Assignee: Caliper Life Sciences Incorporated (Revvity, Inc.)
• Original Assignee: Caliper Holdings Incorporated
• Inventors: Kechagia, Persefoni, Chien, Ring-Ling, Wang, Benjamin N.
• Application Number:
  US10/206,386
• Publication Number:
  US 20030057092A1
• Time in Patent Office: Days
• US Class Current: 204/450
• CPC Class Codes: B01L 2200/0631 Purification arrangements, e.g. solid phase extraction [SPE]
• CPC Class Codes: B01L 2200/0673 Handling of plugs of fluid surrounded by immiscible fluid
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2400/0415 electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• 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: G01N 1/40 Concentrating samples
• CPC Class Codes: G01N 27/44704 Details; Accessories
• CPC Class Codes: G01N 27/44773 Multi-stage electrophoresis, e.g. two-dimensional electrophoresis
• CPC Class Codes: G01N 27/44791 Microapparatus sample containers with integrated microfluidic structures B01L3/5027

Abstract

Methods of concentrating materials within microfluidic channel networks by moving materials into regions in which overall velocities of the material are reduced, resulting in stacking of the material within those reduced velocity regions. These methods, devices and systems employ static fluid interfaces to generate the differential velocities, as well as counter-current flow methods, to concentrate materials within microscale channels.

Claims

1. A method for enhancing detection of a material, comprising:

providing a device comprising at least first, second, and third channels which intersect and are fluidly coupled to a fourth channel and a source of a sample material in fluid communication with at least said first channel, wherein said first channel intersects said fourth channel at an opposite side of and at a channel region which is located between the intersection of the second and third channels with the fourth channel;

hydrodynamically loading said sample material comprising at least a first species in a low conductivity buffer into the first channel and directing the sample material into the second and third channels while loading fluid of high conductivity buffer from opposite ends of the fourth channel into the second and a third channels so that the low conductivity buffer of the sample material forms at least two fluid interfaces with the high conductivity buffer;

applying an electric field along a length of the fourth channel to concentrate at least said first species at a substantially static interfaces created at one of said at least two fluid interfaces, whereby detection of said first species is enhanced,

2. The method of claim 1, wherein the sample material comprises an antibody/antigen mixture.

3. The method of claim 1, wherein the detection is enhanced by an increase in concentration of said first species.

4. The method of claim 1, wherein the sample material comprises at least a first and a second species.

5. The method of claim 4, wherein the detection is further enhanced by electrophoretically separating the first species from the second species.

6. The method of claim 5, wherein the second species is transported to a location other than a detection region of the device.

7. The method of claim 1, wherein the at least first species is negatively charged.

8. The method of claim 1, wherein the at least first species is positively charged.

9. The method of claim 1, wherein the at least first species comprises nucleic acids.

10. The method of claim 1, wherein the at least first species comprises polypeptides.

11. The method of claim 1, wherein the sample material comprise a mixture of different materials.

12. The method of claim 1, wherein the applying step comprises applying an electric field of a sufficient magnitude and for a sufficient duration to concentrate the at least first species at least 2 fold.

13. The method of claim 1, wherein the applying step comprises applying an electric field of a sufficient magnitude and for a sufficient duration to concentrate the first species at least 5 fold.

14. The method of claim 1, wherein the applying step comprises applying an electric field of a sufficient magnitude and for a sufficient duration to concentrate the first species at least 10 fold.

15. The method of claim 1, wherein the applying step comprises applying an electric field of a sufficient magnitude and for a sufficient duration to concentrate the first species at least 100 fold.