Microfluidics devices and methods for performing cell based assays

• US 20020106786A1
• Filed: 05/15/2001
• Published: 08/08/2002
• Est. Priority Date: 05/15/2000
• Status: Active Grant

• Current Assignee: Tecan Trading AG (Tecan Group AG)
• Original Assignee: Tecan Trading AG (Tecan Group AG)
• Inventors: Sheppard, Norman F. Jr., Carvalho, Bruce L., Feakes, Christina, Kellogg, Gregory J.
• Granted Patent: US 6,818,435 B2
• Time in Patent Office: Days
• US Class Current: 435/287.3
• CPC Class Codes: A63B 63/083 for basketball
• CPC Class Codes: B01F 25/4331 Mixers with bended, curved, coiled, wounded mixing tubes or comprising elements for bending the flow
• CPC Class Codes: B01F 33/30 Micromixers
• CPC Class Codes: B01F 35/71 Feed mechanisms with proportioning B01F35/80
• CPC Class Codes: B01F 35/712 for feeding fluids
• CPC Class Codes: B01F 35/71725 using centrifugal forces
• CPC Class Codes: B01F 35/71805 using valves, gates, orifices or openings
• CPC Class Codes: B01L 2200/0605 Metering of fluids
• CPC Class Codes: B01L 2300/0806 Standardised forms, e.g. compact disc [CD] format
• CPC Class Codes: B01L 2300/0864 comprising only one inlet and multiple receiving wells, e.g. for separation, splitting
• CPC Class Codes: B01L 2300/0867 Multiple inlets and one sample wells, e.g. mixing, dilution
• CPC Class Codes: B01L 2300/0874 Three dimensional network
• CPC Class Codes: B01L 2300/10 Means to control humidity and/or other gases
• CPC Class Codes: B01L 2300/1805 Conductive heating, heat from thermostatted solids is conducted to receptacles, e.g. heating plates, blocks
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0409 centrifugal forces
• CPC Class Codes: B01L 2400/0677 phase change valves; Meltable, freezing, dissolvable plugs; Destructible barriers
• CPC Class Codes: B01L 2400/0688 surface tension valves, capillary stop, capillary break
• CPC Class Codes: B01L 2400/088 by specific surface properties
• CPC Class Codes: B01L 3/5025 for parallel transport of multiple samples
• CPC Class Codes: B01L 3/5027 : by integrated microfluidic structures, i.e. dimensions of channels and chambers are such that surface tension forces are important, e.g. lab-on-a-chip B01L3/5023 takes precedence; micromixers B01F33/30; microreactors for synthesis B01J19/0093; microcapillary devices in general B81B1/00
• CPC Class Codes: B01L 3/502715 : characterised by interfacing components, e.g. fluidic, electrical, optical or mechanical interfaces
• CPC Class Codes: B01L 3/502723 : characterised by venting arrangements
• CPC Class Codes: B01L 3/50273 : characterised by the means or forces applied to move the fluids micropumps F04B19/006, of the membrane type F04B43/043
• CPC Class Codes: B01L 3/502738 : characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: B01L 7/00 : Heating or cooling apparatus autoclaves B01J3/04; Heat insulating devices
• CPC Class Codes: B01L 7/525 : with physical movement of samples between temperature zones
• CPC Class Codes: G01N 2035/00495 : Centrifuges
• CPC Class Codes: G01N 2035/00504 : combined with carousels
• CPC Class Codes: G01N 2035/00514 : Stationary mixing elements
• CPC Class Codes: G01N 2035/00524 : Mixing by agitating sample carrier
• CPC Class Codes: G01N 21/07 : Centrifugal type cuvettes G01N21/09 takes precedence
• CPC Class Codes: G01N 35/00069 : whereby the sample substrate is of the bio-disk type, i.e. having the format of an optical disk
• CPC Class Codes: Y10T 436/111666 : Utilizing a centrifuge or compartmented rotor

Abstract

This invention provides methods and apparatus for performing microanalytic analyses and procedures, particularly miniaturized cell based assays. These methods are useful for performing a variety of cell-based assays, including drug candidate screening, life sciences research, and clinical and molecular diagnostics.

Claims

3. A Microsystems platform according to claim 1, further comprising a plurality of detection chambers, wherein each detection chamber is fluidly connected by microchannels to one of the plurality of cell culture chambers and one of the plurality of overflow reservoirs, and is positioned on the platform between the cell culture chamber and the overflow reservoir.

4. A microsystem platform of claim 3 wherein the detection reservoirs are optically transparent.

7. A microsystem platform of claim 3 wherein each detection reservoir has a volumetric capacity of from about 2 nL to about 1000 μ

L.

21. A microsystem platform of claim 3 wherein each detection chamber has a volumetric capacity of from about 2 nL to about 1000 μ

L.

15. A centripetally-motivated Microsystems platform comprising:

a rotatable platform comprising a substrate having a surface comprising

a cell suspension reservoir and

a distribution manifold annularly positioned in the platform more distal from the axis of rotation than the cell culture manifold,

wherein the cell suspension reservoir and the distribution manifold are fluidly connected by a microchannel, the platform further comprising

one or a multiplicity of microfluidics structures embedded in the surface of the platform, wherein each microfluidics structure comprises

one or a plurality of cell culture chambers,

wherein each of said cell culture chambers is fluidly connected to the distribution manifold, wherein the platform further comprises

an overflow reservoir, wherein the overflow reservoir is fluidly connected to each of the cell culture chambers,

and wherein fluid within the microchannels of the platform is moved through said microchannels by centripetal force arising from rotational motion of the platform for a time and a rotational velocity sufficient to move the fluid through the micro channels.

38-1. A method for performing a cell-based assay, comprising the steps of:

a) applying a volume of a fluid comprising a cell suspension to the distribution manifold of a microsystem platform of claim 1 when the platform is stationary,

b) rotating the platform at a first rotational speed wherein a portion of the suspension occupies one or a plurality of subvolumes of the distribution manifold,

c) rotating the platform at a second rotational speed that is higher than the first rotational speed wherein the portion of the cell suspension that does not occupy one or a plurality of subvolumes of the distribution manifold is motivated from the distribution manifold to the cell suspension overflow reservoir;

d) rotating the platform at a third rotational speed that is higher than the second rotational speed to motivate fluid flow from the subvolumes of the distribution manifold into one or each of a plurality of cell culture chambers;

e) incubating the platform for a time and under conditions for the cells to attach to the cell culture chamber and grow;

f) applying a volume of a reagent solution to the distribution manifold of a microsystem platform of claim 1 when the platform is stationary,

g) rotating the platform at a first rotational speed wherein a portion of the reagent solution occupies one or a plurality of subvolumes of the distribution manifold,

h) rotating the platform at a second rotational speed that is higher than the first rotational speed wherein the portion of the reagent solution that does not occupy one or a plurality of subvolumes of the distribution manifold is motivated from the distribution manifold to the cell suspension overflow reservoir;

i) rotating the platform at a third rotational speed that is higher than the second rotational speed to motivate fluid flow from the subvolumes of the distribution manifold into one or each of a plurality of cell culture chambers;

j) incubating the platform for a time and under conditions for the cells to interact with the reagent and produce a detectable product; and

k) detecting a product of the biological or biochemical reaction.

39-2. A method according to claim 38, wherein the reagent is a drug lead compound.

40. The apparatus of claim 39, wherein the detector is an optical detector comprising a light source and a photodetector.

40-3. A centripetally-motivated microsystems platform comprising:

a rotatable platform comprising a substrate having a surface comprising a one or a multiplicity of micro fluidics structures embedded in the surface of the platform, wherein each micro fluidics structure comprises

a plurality of cell culture chambers, and

one or a plurality of overflow reservoirs

at least two reagent reservoirs and

a branching dilution microchannel comprising a multiplicity of branches fluidly connected to capillary junctions

wherein each of said cell culture chambers is fluidly connected to at least one of the reagent reservoirs through the branching dilution microchannel and wherein the branching dilution microchannel is fluidly connected to each of the reagent reservoirs,

wherein fluid within the branching dilution microchannel is moved through said microchannel by centripetal force arising from rotational motion of the platform for a time and a rotational velocity sufficient to move the fluid through the microchannel and wherein a portion of the fluid flow from each of the reagent reservoirs flow directly through the branched dilution microchannel into each of the cell culture chambers, and wherein a portion of the fluid flow through the branching dilution microchannel flows through each of the capillary junctions into a separate branch of the branching dilution microchannel, wherein each branch of the branching dilution microchannel is fluidly connected to one cell culture chamber and each branch contains a mixture of fluid from each of the reagent reservoirs in different proportions of the fluids.