Microfluidic particle manipulation

Patent metadata

Field	Value
Publication number	US-10758905-B2
Application number	US-201615775717-A
Country	US
Kind code	B2
Filing date	Nov 11, 2016
Priority date	Nov 11, 2015
Publication date	Sep 1, 2020
Grant date	Sep 1, 2020

Abstract

The present invention relates to the use of acoustic waves for the manipulation and sorting of particles and cells. In an embodiment, there is provided a microfluidic device for manipulating a particle in a fluid suspension, the device comprising: (a) a substrate; (b) a channel defined in the substrate, the channel having an inlet for receiving the fluid suspension and an outlet for discharging the fluid suspension; and (c) an acoustic source configured to deliver a travelling surface acoustic wave transverse the flow of the fluid suspension in the channel, wherein the acoustic source is an interdigital transducer (IDT), the IDT comprises a plurality of concentric circular arcs having a tapered end directed at the channel, and the tapered end has an aperture of between 4 μm and 150 μm. In an alternative embodiment, the device comprises a second channel disposed intermediate the first channel and the acoustic source wherein the first and second channels are connected by a pumping channel.

First claim

The invention claimed is:

1. A microfluidic device for manipulating a particle in a fluid suspension, the device comprising:
(a) a substrate;
(b) a first channel defined in the substrate, the first channel having an inlet for receiving the fluid suspension and an outlet for discharging the fluid suspension; and
(c) an acoustic source configured to generate and deliver a single travelling surface acoustic wave transverse the flow of the fluid suspension in the channel and configured to propagate into the solution confined within the channel, wherein the acoustic source is a single interdigital transducer (IDT), and the IDT comprises a plurality of concentric arcs having a tapered end directed at the channel, and the tapered end has an aperture of between 4 μm and 150 μm.

2. The device according to claim 1 , wherein the aperture is 56 μm.

3. The device according to claim 1 , further comprising a second channel defined in the substrate, the second channel having an inlet for receiving a fluid and an outlet for discharging the fluid, the second channel is disposed intermediate the first channel and the acoustic source,
wherein the first and second channels are disposed alongside each other and the direction of flow of fluids in the first and second channels are in the same direction, the first and second channels are connected in fluid communication by a pumping channel disposed between the first and second channels, the pumping channel connecting the first and second channels is disposed intermediate the inlets and outlets of both the first and second channels, and the acoustic source is disposed adjacent the second channel to generate and deliver the travelling surface acoustic wave transverse the flow of the fluid from the second channel to the first channel through the pumping channel, the flow of the fluid from the pumping channel to the first channel manipulates the particle in the fluid suspension in the first channel.

4. The device according to claim 3 , wherein each of the first and second channels has a width of about 120 μm and a height of about 25 μm.

5. The device according to claim 4 , wherein the width of the second channel adjacent the acoustic source is narrower than the width of the second channel at the inlet and outlet.

6. The device according to claim 5 , wherein the width of the second channel adjacent the acoustic source is about 20 μm.

7. The device according to claim 3 , wherein the pumping channel has a width of about 20 μm and a length of about 170 μm.

8. The device according to claim 3 , wherein the inlet of each of the first and second channel is in fluid communication with a pump.

9. The device according to claim 1 , wherein the substrate is a piezoelectric substrate selected from the group consisting of: lithium niobate, lithium tantalite, and lanthanum gallium silicate.

10. The device according to claim 1 , wherein the surface acoustic wave has an average frequency of between 100 MHz and 1000 MHz.

11. The device according to claim 1 , wherein the first channel comprises a plurality of outlet channels.

12. A method for manipulating a particle in a fluid suspension, the method comprising:
(a) introducing the fluid suspension along a first channel; and
(b) using an acoustic source to generate a highly focused travelling surface acoustic wave transverse the flow of the fluid suspension in the first channel to manipulate the particle travelling in the first channel, wherein the acoustic source is an interdigital transducer (IDT), the IDT comprises a plurality of concentric arcs having a tapered end directed at the channel, and the tapered end has an aperture of between 4 μm and 150 μm.

13. The method according to claim 12 , wherein the aperture is 56 μm.

14. The method according to claim 12 , further comprising:
(a) introducing a fluid along a second channel, the second channel disposed alongside the first channel, the fluids in both channel travelling in the same direction, the second channel intermediate the first channel and the acoustic source;
(b) connecting in fluid communication the second channel to the first channel with a pumping channel, the pumping channel disposed between the first and second channels, and intermediate the inlets and outlets of both the first and second channels, wherein the acoustic source is disposed adjacent the second channel on the opposing side of the first channel to generate and deliver the travelling surface acoustic wave transverse the flow of the fluid in the second channel and to pump the fluid from the second channel to the first channel through the pumping channel, and manipulating the particle in the fluid suspension in the first channel with the flow of the fluid from the pumping channel.

15. The method according to claim 14 , wherein width of the second channel adjacent the acoustic source is narrower than the width of the second channel at the inlet and outlet, thereby constricting the flow of the fluid in the second channel adjacent the acoustic source.

16. The method according to claim 15 , wherein the width of the second channel adjacent the acoustic source is about 20 μm.

17. The method according to claim 14 , wherein the pumping channel has a width of about 20 μm and a length of about 170 μm.

18. The method according to claim 14 , wherein the inlet of each of the first and second channel is in fluid communication with a pump for pumping fluid through the channels.

19. The method according to claim 14 , wherein the surface acoustic wave has an average frequency of between 100 MHz and 1000 MHz.

20. An interdigital transducer comprising a plurality of concentric circular arcs having a tapered end, wherein the tapered end has an aperture of between 4 μm and 150 μm and wherein the interdigital transducer is configured to generate a travelling the surface acoustic wave placed adjacent a microfluidic channel to deliver the wave transverse the flow of the fluid suspension in the channel.

Assignees

• Univ Singapore Technology & Design

Inventors

• Ai Ye
• Collins David John

Classifications

• B01L2400/0436

  acoustic forces, e.g. surface acoustic waves [SAW] · CPC title

• B01L2300/0864

  comprising only one inlet and multiple receiving wells, e.g. for separation, splitting · CPC title

• B01L3/502761 Primary

  specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads or physically stretching molecules · CPC title

• B01L3/502776

  specially adapted for focusing or laminating flows · CPC title

• B01L2300/0816

  Cards, e.g. flat sample carriers usually with flow in two horizontal directions · CPC title