Acoustic waves in microfluidics

Patent metadata

Field	Value
Publication number	US-12576401-B2
Application number	US-202117550612-A
Country	US
Kind code	B2
Filing date	Dec 14, 2021
Priority date	Aug 23, 2010
Publication date	Mar 17, 2026
Grant date	Mar 17, 2026

Abstract

Various aspects of the present invention relate to the control and manipulation of fluidic species, for example, in microfluidic systems. In one set of embodiments, droplets may be sorted using surface acoustic waves. The droplets may contain cells or other species. In some cases, the surface acoustic waves may be created using a surface acoustic wave generator such as an interdigitated transducer, and/or a material such as a piezoelectric substrate. The piezoelectric substrate may be isolated front the microfluidic substrate except at or proximate the location where the droplets arc sorted, e.g., into first or second microfluidic channels. At such locations, the microfluidic substrate may be coupled to the piezoelectric substrate (or other material) by one or more coupling regions. In some cases, relatively high sorting rates may be achieved, e.g., at rates of at least about 1,000 Hz, at least about 10,000 Hz, or at least about 100,000 Hz, and in some embodiments, with high cell viability after sorting.

First claim

What is claimed is:

1 . A method, comprising:
providing a piezoelectric substrate, an interdigitated transducer to generate surface acoustic waves, and a microfluidic substrate coupled to the piezoelectric substrate at at least first and second coupling regions, wherein the microfluidic substrate comprises an inlet microfluidic channel, a first channel, a second channel and a third channel, meeting at a single junction; directing a plurality of droplets in an homogeneous continuous flow through the inlet microfluidic channel to the single junction between the inlet microfluidic channel, the first channel, the second channel, and the third channel; selectively applying at the single junction, using the interdigitated transducer, a first travelling surface acoustic wave through the first coupling region to create a first acoustic streaming that deflects some of the droplets to cause the droplets to enter the first channel and a second travelling surface acoustic wave through the second coupling region to create a second acoustic streaming that deflects some of the droplets to cause the droplets to enter the second channel, wherein in the absence of the first or second travelling surface acoustic waves, the droplets enter the third channel.

2 . The method of claim 1 , wherein the first surface acoustic wave and/or the second surface acoustic wave has an average frequency of between about 130 MHz and about 160 MHz.

3 . The method of claim 1 , wherein the first surface acoustic wave and/or the second surface acoustic wave has an average frequency of between about 140 MHz and about 150 MHz.

4 . The method of claim 1 , wherein at least some of the plurality of droplets contain cells.

5 . The method of claim 1 , wherein providing a plurality of droplets comprises providing a plurality of droplets of a first fluid contained in a second fluid.

6 . The method of claim 1 , wherein the plurality of droplets is substantially monodisperse.

7 . The method of claim 1 , wherein the droplets enter the first channel, second channel or third channel at a rate of at least about 1,000 Hz.

Assignees

• Harvard College
• Univ Augsburg

Inventors

• Weitz David A
• Franke Thomas
• Wixforth Achim
• Schmid Lothar
• Agresti Jeremy
• Abate Adam R

Classifications

• F17D3/01

  for controlling, signalling, or supervising the conveyance of a product · CPC title

• C12M23/16 Primary

  Microfluidic devices; Capillary tubes (integrated microfluidic structures B01L3/5027; microreactors B01J19/0093) · CPC title

• G01N2015/1028

  Sorting particles · CPC title

• G01N2015/1006

  for cytology · CPC title

• B01L2400/0496

  Travelling waves, e.g. in combination with electrical or acoustic forces · CPC title