Acoustophoretic device for angled wave particle deflection

Patent metadata

Field	Value
Publication number	US-10550382-B2
Application number	US-201715613790-A
Country	US
Kind code	B2
Filing date	Jun 5, 2017
Priority date	Apr 29, 2015
Publication date	Feb 4, 2020
Grant date	Feb 4, 2020

Abstract

Devices for separating materials from a host fluid are disclosed. The devices include a flow chamber, an ultrasonic transducer, and a reflector. The ultrasonic transducer and reflector create an angled acoustic standing wave oriented at an angle relative to the direction of mean flow through the flow chamber. The angled acoustic standing wave results in an acoustic radiation force having an axial force component that deflects the materials, so that the materials and the host fluid can thus be separated. The angled acoustic standing wave can be oriented at an angle of about 20° to about 70° relative to the direction of mean flow through the flow chamber to deflect, collect, differentiate, or fractionate the materials from the fluid flowing through the device at flow rates of about 400 mL/min up to about 700 mL/min.

First claim

The invention claimed is:

1. A method of separating a second fluid, a cell, or a particulate from a host fluid, the method comprising:
flowing an initial mixture of the host fluid and at least one of the second fluid, cell, or particulate through an acoustophoresis device, the acoustophoresis device comprising:
a flow chamber defining a direction of mean flow;
at least one ultrasonic transducer including a piezoelectric material configured to be excited to generate a bulk angled acoustic standing wave and an acoustic radiation force in the flow chamber, the bulk angled acoustic standing wave being oriented at an acute angle relative to the direction of mean flow through the flow chamber; and
a reflector opposite the at least one ultrasonic transducer; and

exciting the at least one ultrasonic transducer such that the bulk angled acoustic standing wave is created in the flow chamber to deflect the second fluid, cell, or particulate irrespective of gravity and transverse to the direction of mean flow; and
controlling a ratio of the acoustic radiation force to a viscous drag force of the mixture of the host fluid and the at least one of the second fluid, cell, or particulate to determine a deflection amount.

2. The method of claim 1 , wherein the bulk angled acoustic standing wave is oriented at an angle of about 5° to about 85° relative to the direction of mean flow through the flow chamber.

3. The method of claim 1 , wherein the acoustophoresis device further comprises an inlet at a first end of the flow chamber and at least two outlets at a second end of the flow chamber opposite the first end.

4. The method of claim 3 , further comprising flowing the initial mixture into the inlet and flowing one or more of a concentrate or a clarified fluid out of one or the other of the at least two outlets at the second end of the flow chamber.

5. The method of claim 3 , further comprising deflecting the at least one of the second fluid, cell or particulate towards a deflection wall to contribute to collecting the at least one of the second fluid, cell or particulate.

6. The method of claim 1 , wherein the acoustophoresis device further comprises at least three outlets, and the method further comprises deflecting a first group of the at least one of the second fluid, cell or particulate to a first one of the at least three outlets, and deflecting a second group of the at least one of the second fluid, cell or particulate to a second one of the at least three outlets that is distinct from the first one of the at least three outlets, based on the ratio.

7. The method of claim 1 , wherein the bulk angled acoustic standing wave is a multi-dimensional acoustic standing wave that results in an acoustic radiation force with an axial force component that deflects the second fluid, cell, or particulate.

8. The method of claim 1 , further comprising collecting the second fluid, cell, or particulate from the acoustophoresis device at a flow velocity of about 0 cm/min to about 24 cm/min or higher.

9. The method of claim 1 , further comprising flowing the mixture of the host fluid and at least one of the second fluid, cell, or particulate through the acoustophoresis device at a flow rate of about 400 to about 700 milliliters per minute or higher.

10. The method of claim 1 , further comprising exciting the at least one transducer with a voltage signal of from about 5 V to about 200 V.

11. The method of claim 1 , further comprising operating the at least one ultrasonic transducer at a frequency of about 0.2 MHz to about 20 MHz.

12. The method of claim 1 , wherein the at least one ultrasonic transducer includes a plurality of ultrasonic transducers arranged in series, each transducer including a piezoelectric material, the method comprising exciting each transducer to create a bulk angled acoustic standing wave in the flow chamber oriented at an angle of about 5° to about 85° relative to the direction of mean flow through the flow chamber.

13. The method of claim 12 , wherein each transducer is oriented at the same angle relative to the direction of mean flow through the flow chamber.

14. The method of claim 1 , wherein the bulk angled acoustic standing wave is a three-dimensional acoustic standing wave.

15. The method of claim 1 , wherein the ratio of the acoustic radiation force to the viscous drag force is about 0.000001 or higher.

16. The method of claim 15 , wherein the at least one ultrasonic transducer includes a plurality of ultrasonic transducers arranged in series and sequenced about 90°, each transducer including a piezoelectric material driven by a voltage signal to create an angled three-dimensional acoustic standing wave in the flow chamber oriented at an angle of about 20° to about 70° relative to the direction of mean flow through the flow chamber to benefit differentiation, separation, concentration or fractionization of the second fluid, cell, or particulate.

17. The method of claim 1 , wherein the acoustophoresis device is operated such that the acoustic radiation force is large enough to retard the second fluid, cell, or particulate from passing through the bulk angled acoustic standing wave.

18. The method of claim 1 , further comprising:
flowing the initial mixture of the host fluid and at least one of the second fluid, cell, or particulate into the acoustophoresis device via a first inlet duct;
flowing a cell wash into the acoustophoresis device via a second inlet duct adjacent to the first inlet duct;
flowing the host fluid of the initial mixture out of the acoustophoresis device via a first exit duct; and
flowing second fluid, cell, or particulate concentrates out of a second exit duct after passing from the flow of the initial mixture via the first inlet duct through the cell wash flowed via the second inlet duct.

19. The method of claim 1 , wherein the ratio is defined by a non-dimensional parameter M where

M
=

π
3

⁢

r
p
2

⁢
β
⁢

⁢

P
0
2

⁢
φ

μλ
⁢

⁢
V

and r p is a characteristic radius of the at least one of the second fluid, cell or particulate, β is the compressibility of the fluid medium, P 0 is acoustic pressure amplitude, φ is an acoustic contrast factor of the at least one of the second fluid, cell or particulate, μ is the fluid viscosity, and λ is the acoustic wavelength and V is the fluid free stream velocity.

20. The method of claim 19 , further comprising modulating the pressure amplitude Po or the fluid free stream velocity V to vary M to control the deflection of the at least one of the second fluid, cell or particulate.

21. The method of claim 1

Assignees

• Flodesign Sonics Inc

Inventors

• Lipkens Bart
• Presz Jr Walter M
• Chitale Kedar
• Kennedy Iii Thomas J
• Ross-Johnsrud Ben

Classifications

• B01L2400/0436

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

• G01N2015/1006

  for cytology · CPC title

• B01L2400/0439

  ultrasonic vibrations, vibrating piezo elements · CPC title

• G01N2015/0053

  in liquids, e.g. trouble · CPC title

• B01L2300/0867

  Multiple inlets and one sample wells, e.g. mixing, dilution · CPC title