Disposable cartridge for microfluidics system

Patent metadata

Field	Value
Publication number	US-9915631-B2
Application number	US-201414361556-A
Country	US
Kind code	B2
Filing date	Jan 6, 2014
Priority date	Jan 9, 2013
Publication date	Mar 13, 2018
Grant date	Mar 13, 2018

Abstract

A digital microfluidics system for manipulating samples in liquid droplets within a gap between a first hydrophobic surface of a bottom layer and a second hydrophobic surface of at least one disposable cartridge. Disposable cartridges comprise a body and/or a rigid cover plate. The bottom layer of each disposable cartridge is a flexible film that is sealingly attached to the body or plate. The cartridge has no spacer between the first and second hydrophobic surfaces. When using these cartridges, the bottom layers configured as a working film for manipulating samples in liquid droplets thereon, is placed on an electrode array of a digital microfluidics system. The array has individual electrodes. The digital microfluidics system also comprises a central control unit for controlling the selection of the individual electrodes of the electrode array and for providing these electrodes with individual voltage pulses for manipulating liquid droplets by electrowetting.

First claim

What is claimed is:

1. A digital microfluidics system ( 1 ) for manipulating samples in liquid droplets within a gap ( 6 ) between a first hydrophobic surface ( 17 ′) of a bottom layer ( 3 ) and a second hydrophobic surface ( 17 ″) of at least one disposable cartridge ( 2 ), the digital microfluidics system ( 1 ) comprising:
(a) a base unit ( 7 ) with at least one cartridge accommodation site ( 8 ) that is configured for taking up said at least one disposable cartridge ( 2 );
(b) an electrode array ( 9 ) located at said at least one cartridge accommodation site ( 8 ) of the base unit ( 7 ), the electrode array ( 9 ) being supported by a bottom substrate ( 11 ), substantially extending in a first plane and comprising a number of individual electrodes ( 10 ); and
(c) a central control unit ( 14 ) for controlling the selection of the individual electrodes ( 10 ) of said electrode array ( 9 ) and for providing these electrodes ( 10 ) with individual voltage pulses for manipulating liquid droplets ( 23 ) within the gap ( 6 ) of said at least one disposable cartridge ( 2 ) by electrowetting,

wherein the digital microfluidics system ( 1 ) further comprises:
(d) a number of suction holes ( 35 ) that penetrate the electrode array ( 9 ) and/or the bottom substrate ( 11 ) and that are located at the at least one cartridge accommodation site ( 8 ) of the base unit ( 7 );
(e) a vacuum source ( 33 ) for establishing an underpressure in at least one of an evacuation space ( 46 ) and a vacuum space ( 50 ); and
(f) a number of vacuum lines ( 34 ) that link the suction holes ( 35 ) and/or vacuum space ( 50 ) to the vacuum source ( 33 );

wherein a gasket ( 36 ) or a number of seals ( 39 , 39 ′), when the at least one disposable cartridge ( 2 ) is located at the at least one cartridge accommodation site ( 8 ), seal in said at least one cartridge accommodation site ( 8 ) the evacuation space ( 46 ), which is defined by a flexible bottom layer ( 3 ) of the at least one disposable cartridge ( 2 ), an uppermost surface ( 52 ) of the at least one cartridge accommodation site ( 8 ), and the gasket ( 36 ) or the seals ( 39 , 39 ′) which are supported by an insertion guide and closing means ( 25 , 30 ); and wherein the underpressure in the evacuation space ( 46 ) causes the flexible bottom layer ( 3 ) of the at least one disposable cartridge ( 2 ) that is placed at the at least one cartridge accommodation site ( 8 ) to be attracted and spread over the uppermost surface ( 52 ) of the at least one cartridge accommodation site ( 8 ) of the digital microfluidics system ( 1 ).

2. The digital microfluidics system ( 1 ) of claim 1 , wherein the gasket ( 36 ) is dimensioned to define a height of the gap ( 6 ) between the first hydrophobic surface ( 17 ′) of the bottom layer ( 3 ) and the second hydrophobic surface ( 17 ″) of the at least one disposable cartridge ( 2 ).

3. The digital microfluidics system ( 1 ) of claim 1 , wherein the electrode array ( 9 ) of the digital microfluidics system ( 1 ) comprises a rigid spacer ( 5 ) that is dimensioned to define a height of the gap ( 6 ) between the first hydrophobic surface ( 17 ′) of the bottom layer ( 3 ) and the second hydrophobic surface ( 17 ″) of the at least one disposable cartridge ( 2 ).

4. The digital microfluidics system ( 1 ) of claim 1 , wherein the suction holes ( 35 ) are configured to mouth into suction channels ( 51 ), said suction channels ( 51 ) being arranged in the uppermost surface ( 52 ) of the at least one cartridge accommodation site ( 8 ) of the digital microfluidics system ( 1 ).

5. The digital microfluidics system ( 1 ) of claim 1 , wherein the suction holes ( 35 ) are configured to mouth into a vacuum space ( 50 ), said vacuum space ( 50 ) being arranged at the at least one cartridge accommodation site ( 8 ) and under the electrode array ( 9 ) in the bottom substrate ( 11 ), said vacuum space ( 50 ) being connected to the vacuum source ( 33 ) of the digital microfluidics system ( 1 ) by at least one of the vacuum lines ( 34 ).

6. The digital microfluidics system ( 1 ) of claim 1 , wherein the uppermost surface ( 52 ) of the at least one cartridge accommodation site ( 8 ) comprises a dielectric layer ( 24 ) that covers the electrode array ( 9 ), the dielectric layer ( 24 ) having holes at the sites of the of suction holes ( 35 ) of the base unit ( 7 ).

7. The digital microfluidics system ( 1 ) of claim 1 , wherein the gasket ( 36 ) is permanently fixed to the electrode array ( 9 ) of the at least one cartridge accommodation site ( 8 ) of the base unit ( 7 ) of the digital microfluidics system ( 1 ).

8. The digital microfluidics system ( 1 ) of claim 6 ,
wherein the gasket ( 36 ) is fixed to the dielectric layer ( 24 ) that permanently covers the electrode array ( 9 ) of the at least one cartridge accommodation site ( 8 ) of the digital microfluidics system ( 1 ).

9. The digital microfluidics system ( 1 ) of claim 6 ,
wherein the gasket ( 36 ) is permanently fixed to the bottom substrate ( 11 ) that supports the electrode array ( 9 ); the dielectric layer ( 24 ) permanently covering the bottom substrate ( 11 ), the electrode array ( 9 ), and the gasket ( 36 ).

10. The digital microfluidics system ( 1 ) of claim 1 , wherein the base unit ( 7 ) comprises an insertion guide ( 25 ) that is configured as a frame, which is sized to accommodate the at least one disposable cartridge ( 2 ) therein.

11. The digital microfluidics system ( 1 ) of claim 3 , wherein the base unit ( 7 ) comprises a closing means ( 30 ) that is configured as a pressing plate for pressing the at least one disposable cartridge ( 2 ) to the rigid spacer ( 5 ) of the electrode array ( 9 ) of the digital microfluidics system ( 1 ).

12. The digital microfluidics system ( 1 ) of claim 1 , wherein the base unit ( 7 ) comprises a clamp ( 37 ) that is configured to fix the at least one disposable cartridge ( 2 ) at a desired position of the at least one cartridge accommodation site ( 8 ) of the base unit ( 7 ).

13. A disposable cartridge ( 2 ) that is configured for insertion into a cartridge accommodation site ( 8 ) of a digital microfluidics system ( 1 ) according to claim 1 , the disposable cartridge ( 2 ) comprising:
(a) a body ( 47 ) with at least one compartment ( 21 ) configured to hold therein processing liquids, reagents or samples, at least one of said compartments ( 21 ) comprising a through hole ( 19 ) for delivering at least some of its content;
(b) a bottom layer ( 3 ) with a first hydrophobic surface ( 17 ′) that is impermeable to liquids and that is configured as a working film for manipulating samples in liquid droplets ( 23 ) thereon utilizing an electrode array ( 9 ) of the digital microfluidics system ( 1 ) when the bottom layer ( 3 ) of the disposable cartridge ( 2 ) is placed over said electrode array ( 9 );
(c) a top layer ( 4 ) with a second hydrophobic surface ( 17 ″) that is attached to a lower surface ( 48 ) of the body ( 47 ) of the disposable cartridge ( 2 ) and that at least is permeable to ions; and
(d) a gap ( 6 ) that is located between the first hydrophobic surface ( 17 ′) of the bottom layer ( 3 ) and the second hydrophobic surface ( 17 ″) of the top layer ( 4 ),

wherein the bottom layer ( 3 ) is configured as a flexible film that is sealingly attached to the top layer ( 4 ) or to the body ( 47 ) along a circumference ( 40 ) of the flexible bottom layer ( 3 ), the flexible bottom layer ( 3 ) being configured to be attracted and spread over the uppermost surface ( 52 ) of a cartridge accommodation site ( 8 ) of the digital microfluidics system ( 1 ) by the underpressure in the evacuation space ( 46 ) of the

Assignees

• Tecan Trading Ag

Inventors

• Hoffmeyer Daniel
• Lay Tiffany
• Lee Travis

Classifications

• B01L3/502792

  for moving individual droplets on a plate, e.g. by locally altering surface tension · CPC title

• B01L2400/0427

  Electrowetting · CPC title

• B01L2200/027

  for microfluidic devices · CPC title

• B81B1/00

  Devices without movable or flexible elements, e.g. microcapillary devices · CPC title

• B01L2200/04

  Exchange or ejection of cartridges, containers or reservoirs · CPC title