Microfluidics cartridge with pipetting guide

Patent metadata

Field	Value
Publication number	US-10137450-B2
Application number	US-201414335027-A
Country	US
Kind code	B2
Filing date	Jul 18, 2014
Priority date	Jul 18, 2014
Publication date	Nov 27, 2018
Grant date	Nov 27, 2018

Abstract

A disposable cartridge configured as a digital microfluidics system for manipulating samples in liquid portions having a cartridge accommodation site and a central control unit for controlling selection of individual electrodes of an electrode array located at the site and for providing plural electrodes with individual voltage pulses for manipulating liquid portions by electrowetting. The cartridge has a hydrophobic working surface and a rigid cover with a second hydrophobic surface, the hydrophobic surfaces facing each other and being separated in parallel planes by a gap. The cartridge has plural pipetting guides for safe entering/withdrawing liquids into/from the gap with a pipette tip. At least one of the pipetting guides provides an abutting surface sealingly admittable by a counter surface of a pipette tip, located at a pipetting orifice that reaches through the rigid cover, and configured to prevent a pipette tip from touching the hydrophobic working surface.

First claim

What is claimed is:

1. A disposable cartridge ( 1 ) for use in a digital microfluidics system ( 3 ) for manipulating samples in liquid portions or droplets ( 4 ); the digital microfluidics system ( 3 ) comprising a cartridge accommodation site ( 2 ) and a central control unit ( 7 ) for controlling the selection of individual electrodes ( 8 ) of an electrode array ( 5 ) located at said cartridge accommodation site ( 2 ) and for providing a number of said electrodes ( 8 ) with individual voltage pulses for manipulating liquid portions or droplets ( 4 ) by electrowetting; the disposable cartridge ( 1 ) comprising a hydrophobic working surface ( 10 ) and a rigid cover ( 11 ) with a second hydrophobic surface ( 12 ); said hydrophobic surfaces ( 10 , 12 ) facing each other and being separated or being separable in essentially parallel planes by a gap ( 13 ) with a gap height ( 14 ):
wherein the disposable cartridge ( 1 ) further comprises a number of pipetting guides ( 17 ) for safe entering and/or withdrawing liquids into and/or from the gap ( 13 ) of the disposable cartridge ( 1 ) with a tip ( 18 ) of a pipette ( 19 ); at least one of the pipetting guides ( 17 ):
being located at a pipetting orifice ( 22 ) that reaches through the rigid cover ( 11 ), and
being configured to prevent a pipette tip ( 18 ) from touching the hydrophobic working surface ( 10 ), and
providing an abutting surface ( 20 ) that is sealingly admittable by a counter surface ( 21 ) of a pipette tip ( 18 ),

wherein the pipetting guide comprises a shoulder and a first conical wall with a narrow end at the shoulder that provides the abutting surface.

2. The disposable cartridge ( 1 ) of claim 1 ,
wherein the disposable cartridge ( 1 ) comprises an electrode array ( 5 ) supported by a substrate ( 6 ), said electrode array ( 5 ) comprising the hydrophobic working surface ( 10 );
and wherein said substrate ( 6 ) comprises a backside ( 15 ) that is configured to touch an uppermost surface ( 16 ) of said cartridge accommodation site ( 2 ) of the digital microfluidics system ( 3 ).

3. The disposable cartridge ( 1 ) of claim 1 ,
wherein the digital microfluidics system ( 3 ) comprises at said cartridge accommodation site ( 2 ) an electrode array ( 5 ) supported by a substrate ( 6 );
and wherein the disposable cartridge ( 1 ) comprises a working film ( 9 ) with the hydrophobic working surface ( 10 ), said working film ( 9 ) comprising a backside ( 15 ) that is configured to touch an uppermost surface ( 16 ) of said cartridge accommodation site ( 2 ) of the digital microfluidics system ( 3 ).

4. The disposable cartridge ( 1 ) of claim 3 ,
wherein the working film ( 9 ) of the disposable cartridge ( 1 ) is configured as a flexible sheet that spreads on the uppermost surface ( 16 ) of said cartridge accommodation site ( 2 ) of the digital microfluidics system ( 3 ) which comprises a vacuum source ( 30 ) for establishing an underpressure in an evacuation space ( 34 ) between the uppermost surface ( 16 ) of the cartridge accommodation site ( 2 ) and the backside ( 15 ) of the working film ( 9 ) of the disposable cartridge ( 1 ).

5. The disposable cartridge ( 1 ) of claim 4 ,
wherein the cartridge accommodation site ( 2 ) of the digital microfluidics system ( 3 ) or the disposable cartridge ( 1 ) comprise a gasket ( 33 ) that sealingly encloses said evacuation space ( 34 ) and that defines the height ( 14 ) of the gap ( 13 ) between said hydrophobic surfaces ( 10 , 12 ) of the disposable cartridge ( 1 ).

6. The disposable cartridge ( 1 ) of claim 3 ,
wherein the rigid cover ( 11 ) is configured as a plate with the second hydrophobic surface ( 12 ) on one side and said pipetting guides ( 17 ) on an opposite side, a number of pipetting guides ( 17 ) being configured as ring-like elevations around pipetting orifices ( 22 ) and on the side opposite to the second hydrophobic surface ( 12 ) of the rigid cover ( 11 ) of the disposable cartridge ( 1 ).

7. The disposable cartridge ( 1 ) of claim 6 ,
wherein, the at least one of the pipetting guides ( 17 ) is configured for perpendicular or slanted introduction or withdrawal of a pipette tip ( 18 ), in that the pipetting guide ( 17 ) comprises a first conical wall with a narrow end at an arcuated shoulder ( 23 ) that provides the abutting surface ( 20 ) which sealingly is admittable by a counter surface of the pipette tip ( 18 ).

8. The disposable cartridge ( 1 ) of claim 6 ,
wherein at least one of the pipetting guides ( 17 ) is configured for slanted introduction or withdrawal of a pipette tip ( 18 ), in that the pipetting guide ( 17 ) comprises a first conical wall that is adapted to the outer surface of a pipette tip ( 18 ) and that provides the abutting surface ( 20 ) which sealingly is admittable by an outer conical surface of the pipette tip ( 18 ).

9. The disposable cartridge ( 1 ) of claim 6 ,
wherein a number of pipetting guides ( 17 ) further comprises a second conical wall that is wider than the first conical wall and that serves as additional insertion guide for the pipette tip ( 18 ).

10. The disposable cartridge ( 1 ) of claim 3 ,
wherein a number of pipetting guides ( 17 ) is rigidly connected with each other by reinforcing bars ( 25 ) that are of the same material as the rigid cover ( 11 ) and the pipetting guides ( 17 ), the rigid cover ( 11 ) with pipetting guides ( 17 ) and reinforcing bars ( 25 ) being manufactured by injection molding.

11. The disposable cartridge ( 1 ) of claim 3 ,
wherein the rigid cover ( 11 ) further comprises at least one oil loading port ( 26 ) with at least one oil loading orifice ( 27 ) through which oil is introducible into the gap ( 13 ) of the disposable cartridge ( 1 ), the oil loading port ( 26 ) being configured for sealing attachment of a syringe.

12. The disposable cartridge ( 1 ) of claim 1 , wherein the abutting surface is one of: flat, conical and arcuated.

13. The disposable cartridge ( 1 ) of claim 1 , wherein the pipetting guide is directed to an essentially vertical or a tilted pipetting axis.

14. The disposable cartridge ( 1 ) of claim 1 , wherein the pipetting guide combines the abutting surface with a cylindrical or conical pipetting orifice.

Assignees

• Tecan Trading Ag

Inventors

• Lay Tiffany
• Hoffmeyer Daniel
• Kopf-Sill Anne R

Classifications

• B01L3/0275

  Interchangeable or disposable dispensing tips · CPC title

• B01L3/50273

  characterised by the means or forces applied to move the fluids · CPC title

• B01L2300/0816

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

• B01L3/502792 Primary

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

• B01L2200/027

  for microfluidic devices · CPC title