Cartridge, electrowetting sample processing system and droplet formation

Patent metadata

Field	Value
Publication number	US-11933760-B2
Application number	US-202217901634-A
Country	US
Kind code	B2
Filing date	Sep 1, 2022
Priority date	Apr 25, 2018
Publication date	Mar 19, 2024
Grant date	Mar 19, 2024

Abstract

A cartridge for use in an electrowetting sample processing system, the cartridge having at least one inlet port for introducing an input liquid in an internal gap of the cartridge, wherein the gap has at least one hydrophobic surface and is configured to provide an electrowetting induced movement of a microfluidic droplet of input liquid, wherein the input liquid has a carrier liquid and a processing liquid and the gap has a capture zone that is configured to capture at least a part of the processing liquid as a microfluidic droplet by use of electrowetting force and the gap further has a transfer zone that is configured to provide a passage for the carrier liquid next to the microfluidic droplet, while processing liquid is captured in the capture zone.

First claim

The invention claimed is:

1. A method for operating a cartridge in an electrowetting sample processing system, the cartridge comprising an inlet port and an internal gap, the internal gap comprising at least one hydrophobic surface, a capture zone and a transfer zone, the internal gap being configured to provide an electrowetting induced droplet movement, the method comprising:
introducing an input liquid into the internal gap of the cartridge via the inlet port, the input liquid comprising a carrier liquid and a processing liquid and the introduction of the input liquid is accomplished by alternatingly feeding the processing liquid and the carrier liquid into the inlet port before entering the internal gap; and
capturing in the capture zone at least a part of the processing liquid as a microfluidic droplet by use of electrowetting force and providing a passage for the carrier liquid next to the microfluidic droplet, while the processing liquid is captured in the capture zone.

2. A method for operating a cartridge that comprises an inlet port and an internal gap with a capture zone and a transfer zone, the method comprising:
providing an input liquid that comprises a processing liquid and a carrier liquid and the providing of the input liquid is accomplished by alternatingly feeding the processing liquid and the carrier liquid into the inlet port before entering the internal gap;
capturing a part of the processing liquid in the capture zone by use of electrowetting force;
transferring the carrier liquid from the inlet port to the internal gap via the transfer zone, while the part of the processing liquid is captured in the capture zone; and
using the part of the processing liquid in the capture zone for providing a microfluidic droplet that is movable by applying an electrowetting force to the microfluidic droplet.

3. The method according to claim 1 , wherein the processing liquid comprises multiple liquid parts, and the capturing is accomplished by accumulating these parts for providing the microfluidic droplet.

4. The method according to claim 3 , wherein at least one part of the processing liquid comprising at least one part of the multiple liquid parts, and the at least one part comprises a volume that is insufficient for a transportation by electrowetting and/or a volume of less than 2 μl.

5. The method according to claim 1 , comprising sequentially actuating electrodes for inducing a motion of the microfluidic droplet away from the capture zone, thereby enabling a following part of the processing liquid to be captured.

6. A method for operating a sample processing system comprising a cartridge with an inlet port and an internal gap, the internal gap comprising at least one hydrophobic surface, a capture zone and a transfer zone, the internal gap being configured to provide an electrowetting induced droplet movement, the method comprising:
introducing an input liquid into the internal gap of the cartridge via the inlet port, the input liquid comprising a carrier liquid and a processing liquid and the introducing of the input liquid is accomplished by alternatingly feeding the processing liquid and the carrier liquid into the inlet port before entering the internal gap; and
capturing in the capture zone at least a part of the processing liquid as a microfluidic droplet by use of electrowetting force and providing a passage for the carrier liquid next to the microfluidic droplet, while the processing liquid is captured in the capture zone.

7. The method according to claim 1 , wherein the carrier liquid that is an electrowetting filler liquid and/or a silicone oil.

8. The method according to claim 1 , wherein the processing liquid comprises at least one of:
a reagent liquid,
a buffer,
a diluent,
an extraction liquid,
a washing liquid, and
a suspension.

9. The method according to claim 1 , the cartridge comprising at least an electrode array for applying an electrowetting force to the processing liquid and/or the microfluidic droplet.

10. The method according to claim 1 , the cartridge comprising a first part with the inlet port and a second part attached to the first part, such that the internal gap is formed between the first part and the second part.

11. The method according to claim 1 , wherein the method uses a liquid feeder that is operatively connected to the inlet port by a tube and feeding the input liquid of a predetermined volume to the inlet port.

12. The method according to claim 11 , wherein the method uses a controller for operating the liquid feeder, independently and/or asynchronously from the operation of electrodes used for electrowetting.

13. The method according to claim 1 , wherein the method uses a detector for monitoring the feed of the input liquid.

14. The method according to claim 1 , wherein the transfer zone is provided by an open space, which is located between the inlet port and the top of the microfluidic droplet captured in the capture zone.

15. The method according to claim 1 , wherein the method provides the capture zone or at least one capture electrode, either one being located closest to the inlet port such that the area of the capture zone covers between 5% and 95% of the opening area of the inlet port.

16. The method according to claim 1 , wherein the method provides at least one capture electrode and the area of the capture electrode covers between 10% and 90% of the opening area of the inlet port or between 25% and 75% of the opening area of the inlet port.

17. The method according to claim 1 , wherein the method comprises capturing or accumulating the microfluidic droplet of less than 10 μl in volume.

18. The method according to claim 1 , wherein the inlet port comprises a sealing surface for a tube to be inserted into the inlet port.

19. The method according to claim 1 , wherein the cartridge comprises at least one electrode comprising at least one capture electrode that is configured to capture the part of the processing liquid as the microfluidic droplet by use of electrowetting force, wherein the edge of the at least one capture electrode is arranged with an offset from the axis of flow of the inlet port.

20. The method according to claim 1 , wherein the cartridge comprises at least one electrode, wherein the at least one electrode comprises a transport electrode for removing the microfluidic droplet from the capture zone.

21. The method according to claim 1 , wherein the cartridge is a disposable cartridge.

22. The method according to claim 1 , wherein the sample processing system is a biological sample processing system.

23. The method according to claim 1 , wherein the processing liquid comprises multiple liquid parts of different compositions and the capturing is accomplished by accumulating these parts for providing the microfluidic droplet.

24. The method according to claim 1 , wherein the processing liquid comprises a suspension of at least one of magnetic beads, single cells and cell aggregates.

25. The method according to claim 12 , wherein the method uses a droplet generator for operating the liquid feeder.

26. The method according to claim 1 , wherein the method uses a detector for monitoring the feed of the processing liquid and/or the carrier liquid.

Assignees

• Tecan Trading Ag

Inventors

• Kinney Patrick
• Ngo Tin
• Iyer Sujata
• Hoffmeyer Daniel
• Dhindsa Manjeet
• Ding (Lay) Tiffany

Classifications

• G01N27/44791 Primary

  Microapparatus (sample containers with integrated microfluidic structures B01L3/5027) · CPC title

• B01L3/502715

  characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces · CPC title

• G01N27/44739

  Collecting the separated zones, e.g. blotting to a membrane or punching of gel spots · CPC title

• G01N27/44747

  Composition of gel or of carrier mixture · CPC title

• B01L2200/027

  for microfluidic devices · CPC title