MICROFLUIDIC PROBE HEAD FOR PROCESSING A SEQUENCE OF LIQUID VOLUMES SEPARATED BY SPACERS

• US 20160243549A1
• Filed: 02/11/2016
• Published: 08/25/2016
• Est. Priority Date: 02/13/2015
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: AUTEBERT, JULIEN, DELAMARCHE, EMMANUEL, KAIGALA, GOVIND, VAN KOOTEN, XANDER FRANK
• Granted Patent: US 10,639,631 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B01L 2200/027 for microfluidic devices
• CPC Class Codes: B01L 2200/0636 Focussing flows, e.g. to laminate flows
• CPC Class Codes: B01L 2200/0673 Handling of plugs of fluid surrounded by immiscible fluid
• CPC Class Codes: B01L 2300/0848 Specific forms of parts of containers
• CPC Class Codes: B01L 2300/0861 Configuration of multiple channels and/or chambers in a single devices
• CPC Class Codes: B01L 2300/089 Virtual walls for guiding liquids
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• CPC Class Codes: B01L 2400/086 using baffles or other fixed flow obstructions
• CPC Class Codes: B01L 3/0262 using touch-off at substrate or container
• CPC Class Codes: B01L 3/0293 for liquids
• CPC Class Codes: B01L 3/502715 characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces
• CPC Class Codes: B01L 3/502769 characterised by multiphase flow arrangements
• CPC Class Codes: B01L 3/502784 specially adapted for droplet or plug flow, e.g. digital microfluidics automatic analysis using a stream of discrete samples in a tube system G01N35/08
• CPC Class Codes: G01N 1/28 Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Qmounting specimens on microscopic slides G02B21/34; means for supporting the objects or the materials to be analysed in electron microscopes H01J37/20 ; laboratory gas handling apparatus B01L5/00
• CPC Class Codes: G01N 2035/1034 Transferring microquantities of liquid
• CPC Class Codes: G01N 35/00871 Communications between instruments or with remote terminals
• CPC Class Codes: G01N 35/10 Devices for transferring samples or any liquids to, in, or from, the analysis apparatus, e.g. suction devices, injection devices G01N35/0099 takes precedence

Abstract

Microfluidic probe head for processing a sequence of separate liquid volumes separated by spacers. The microfluidic probe head includes: an inlet, an outlet, a first fluid channel and a second fluid channel and a fluid bypass connecting the first fluid channel and the second fluid channel. The first fluid channel delivers the sequence of separate liquid volumes from the inlet toward a deposition area, the fluid bypass allows the spacers to be removed from the first fluid channel obtaining a free sequence of separate liquid volumes without spacers, the first fluid channel delivers the free sequence of separate liquid volumes to the deposition area, and the second fluid channel delivers the removed spacers from the fluid bypass to the outlet. The present invention also provides a microfluidic probe and method for processing a sequence of separate liquid volumes.

Claims

1. A microfluidic probe head for processing a sequence of separate liquid volumes separated by spacers, the microfluidic probe head comprising:

an inlet and an outlet;

a first fluid channel and a second fluid channel; and

a fluid bypass connecting the first fluid channel and the second fluid channel, wherein the first fluid channel delivers the sequence of separate liquid volumes from the inlet toward a deposition area, the fluid bypass allows the spacers to be removed from the first fluid channel obtaining a free sequence of separate liquid volumes without spacers, the first fluid channel delivers the free sequence of separate liquid volumes to the deposition area, and the second fluid channel delivers the removed spacers from the fluid bypass to the outlet.

2. The microfluidic probe head of claim 1, wherein a spacer separating two subsequent separate liquid volumes of the sequence of separate liquid volumes from each other is immiscible with the separate liquid volumes.

3. The microfluidic probe head of claim 1, wherein the second fluid channel is configured for delivering the free sequence of separate liquid volumes from the deposition area to the outlet.

4. The microfluidic probe head of claim 3, further comprising:

a body including the first fluid channel, the second fluid channel and the fluid bypass, wherein the body has an end face configured for immersion in an immersion liquid;

a first aperture formed in the end face and fluidly connected to the first fluid channel, wherein the fluid bypass connects to the first fluid channel upstream of where the first fluid channel connects to the first aperture; and

a second aperture formed in the end face and fluidly connected to the second fluid channel.

5. The microfluidic probe head of claim 4, wherein a free sequence of separate liquid volumes is delivered through the first aperture and the first fluid channel at a first flow rate and aspirated together with some of the immersion liquid from the deposition area through the second aperture and the second fluid channel at a second flow rate, wherein the second flow rate is greater than the first flow rate so as to confine the delivered free sequence of separate liquid volumes within the immersion liquid.

6. The microfluidic probe head of claim 1, further comprising:

an additional outlet; and

a third fluid channel configured for delivering the free sequence of separate liquid volumes from the deposition area to the additional outlet.

7. The microfluidic probe head of claim 6, further comprising:

a body including the first fluid channel, the second fluid channel, the third fluid channel and the fluid bypass, the body having an end face configured for immersion in an immersion liquid;

a first aperture formed in the end face and fluidly connected to the first fluid channel, wherein the fluid bypass connects to the first fluid channel upstream of where the first fluid channel connects to the first aperture;

a second aperture formed in the end face and fluidly connected to the second fluid channel;

a third aperture formed in the end face and fluidly connected to the third fluid channel.

8. The microfluidic probe head of claim 7, wherein a free sequence of separate liquid volumes is provided through the first aperture and the first fluid channel, some aspirated immersion liquid from the deposition area is provided through the second aperture and the second fluid channel, and the free sequence of separate liquid volumes together is aspirated with some of the immersion liquid from the deposition area through the third aperture and the third fluid channel.

9. The microfluidic probe head of claim 1, further comprising:

at least one blocking element for redirecting the spacers from the first fluid channel into the fluid bypass.

10. The microfluidic probe head of claim 1, wherein the fluid bypass tapers down from the first fluid channel toward the second fluid channel.

11. The microfluidic probe head of claim 1, wherein the second fluid channel includes a constriction configured for increasing a pressure at a location where the fluid bypass connects fluidly to the second fluid channel.

12. The microfluidic probe head of claim 1, further comprising:

a spacer insertion unit for injecting the spacers into the first fluid channel.

13. The microfluidic probe head of claim 1, wherein the sequence includes separated volumes of at least one liquid that contains a biochemical substance.

14. The microfluidic probe head of claim 1, further comprising:

a control unit configured for synchronizing an insertion rate of the spacers into the first fluid channel with an aspiration rate of the spacers into the second fluid channel.

17. The method of claim 14, wherein delivering the sequence of separate liquid volumes, removing the spacers, delivering the free sequence of separate liquid volumes and delivering the removed spacers is carried out using a microfluidic probe head.

18. The method of claim 14, wherein the sequence of separate liquid volumes delivered via the first fluid channel comprises separate volumes of at least two different liquids.

15. A microfluidic probe for processing a sequence of separate liquid volumes separated by spacers, the microfluidic probe comprising:

a microfluidic probe head including an inlet, an outlet, a first fluid channel, a second fluid channel, and a fluid bypass connecting the first fluid channel and the second fluid channel;

a plurality of liquid supplies fluidly connectable to the inlet of the microfluidic probe head; and

a control unit for selectively, fluidly connecting the inlet to one of the plurality of liquid supplies.

16. A method for processing a sequence of separate liquid volumes separated by spacers, the method comprising:

delivering via a first fluid channel the sequence of separate liquid volumes from an inlet toward a deposition area;

removing from the first fluid channel the spacers separating the separate liquid volumes from one another via a fluid bypass that connects the first fluid channel and a second fluid channel, thereby obtaining a free sequence of separate liquid volumes without spacers;

delivering the free sequence of separate liquid volumes to the deposition area; and

delivering the removed spacers from the fluid bypass to an outlet via the second fluid channel.