Capillaries for fluid movement within microfluidic channels

• US 6,557,427 B2
• Filed: 05/23/2001
• Issued: 05/06/2003
• Est. Priority Date: 05/24/2000
• Status: Expired due to Term

• Current Assignee: PerkinElmer Health Sciences, Inc. (Revvity, Inc.)
• Original Assignee: Micronics Inc. (Sony Group Corp.)
• Inventors: Weigl, Bernhard H., Battrell, C. Frederick, Bardell, Ronald L., Klein, Gerald L.
• Primary Examiner(s): Larkin, Daniel S.
• Assistant Examiner(s): GARBER, CHARLES D
• Application Number:
  US09/864,099
• Publication Number:
  US 20020025279A1
• Time in Patent Office: 713 Days
• Field of Search: 738/633.1, 738/647.2, 436/180
• US Class Current: 73/863.31
• CPC Class Codes: B01F 2215/0431 Numerical size values, e.g. diameter of a hole or conduit, area, volume, length, width, or ratios thereof
• CPC Class Codes: B01F 25/433 Mixing tubes wherein the shape of the tube influences the mixing, e.g. mixing tubes with varying cross-section or provided with inwardly extending profiles
• 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 33/3011 using a sheathing stream of a fluid surrounding a central stream of a different fluid, e.g. for reducing the cross-section of the central stream or to produce droplets from the central stream
• CPC Class Codes: B01F 33/3039 with mixing achieved by diffusion between layers
• CPC Class Codes: B01F 35/712 for feeding fluids
• CPC Class Codes: B01F 35/71725 using centrifugal forces
• CPC Class Codes: B01J 19/0093 Microreactors, e.g. miniaturised or microfabricated reactors laboratory containers with capillary fluid transport in microfabricated channels or chambers B01L3/5027
• CPC Class Codes: B01L 2200/0621 Control of the sequence of chambers filled or emptied
• CPC Class Codes: B01L 2200/0636 Focussing flows, e.g. to laminate flows
• CPC Class Codes: B01L 2300/0809 rectangular shaped
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/0867 Multiple inlets and one sample wells, e.g. mixing, dilution
• CPC Class Codes: B01L 2300/087 Multiple sequential chambers
• CPC Class Codes: B01L 2300/0874 Three dimensional network
• CPC Class Codes: B01L 2300/0887 Laminated structure
• CPC Class Codes: B01L 2300/123 Flexible; Elastomeric
• CPC Class Codes: B01L 2300/161 Control and use of surface tension forces, e.g. hydrophobic, hydrophilic
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0457 passive flow or gravitation
• CPC Class Codes: B01L 2400/0481 : squeezing of channels or chambers
• CPC Class Codes: B01L 2400/0638 : membrane valves, flap valves
• CPC Class Codes: B01L 2400/0655 : pinch valves
• CPC Class Codes: B01L 2400/0688 : surface tension valves, capillary stop, capillary break
• 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 3/502738 : characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: B01L 3/502784 : specially adapted for droplet or plug flow, e.g. digital microfluidics automatic analysis using a stream of discrete samples in a tube system G01N35/08
• CPC Class Codes: B01L 7/525 : with physical movement of samples between temperature zones
• CPC Class Codes: B01L 9/527 : for microfluidic devices, e.g. used for lab-on-a-chip
• CPC Class Codes: F15C 1/14 : Stream-interaction devices; Momentum-exchange devices, e.g. operating by exchange between two orthogonal fluid jets ; Proportional amplifiers
• CPC Class Codes: F16K 2099/0084 : Chemistry or biology, e.g. "lab-on-a-chip" technology
• CPC Class Codes: F16K 99/0001 : Microvalves microdevices B81B1/00; manufacture or treatment of devices or systems in or on a substrate B81C1/00; microfluidic structures B01L3/5027; micropumps F04B19/006
• CPC Class Codes: F16K 99/0017 : Capillary or surface tension valves, e.g. using electro-wetting or electro-capillarity effects
• CPC Class Codes: F16K 99/0057 : the fluid being the circulating fluid itself, e.g. check valves
• CPC Class Codes: G01N 2035/00158 : Elements containing microarrays, i.e. "biochip"
• CPC Class Codes: G01N 2035/00237 : Handling microquantities of analyte, e.g. microvalves, capillary networks
• CPC Class Codes: G01N 2035/00247 : Microvalves
• CPC Class Codes: G01N 2035/00495 : Centrifuges
• CPC Class Codes: G01N 21/07 : Centrifugal type cuvettes G01N21/09 takes precedence
• CPC Class Codes: G01N 35/1097 : characterised by the valves valves in general F16K

Abstract

A capillary for introduction of whole blood into an analysis device. The capillary has a variable volume along its length, which allows the liquid sample to be drawn into the interior of the cartridge, away from the inlet, reducing the risk of contamination of the sample from the outside.

Claims

1. A microfluidic device, comprising:

a first channel having an inlet opening, an outlet, and a longitudinal section between said inlet opening and said outlet, said longitudinal section having a first portion, coupled to said inlet opening, sized to generate a first capillary pressure, and a second portion, coupled between said first portion and said outlet and spaced away from said inlet opening, sized to generate a second capillary pressure greater than said first capillary pressure;

a second channel extending away from said first channel;

valve means, coupling said outlet of said first channel to said second channel;

and fluid introduction means;

wherein when a fluid plug is introduced at said inlet opening, said fluid plug is drawn into said first channel such that said fluid plug flows into said second portion of said first channel toward said valve means such that the trailing edge of said fluid plug is completely spaced apart from said inlet opening.

2. The device of claim 1, further comprising valve actuator means for controlling said valve means to selectively couple said first and second channels.

3. The device of claim 2, wherein when said valve actuator means is activated when said fluid is introduced at said inlet opening, said fluid enters said second channel from said first channel.

4. The device of claim 3, wherein fluid is contained within said second channel after said valve actuator means is deactivated.

5. The device of claim 1, wherein said fluid is whole blood.

6. The device of claim 1, wherein at least a portion of said first channel is cone-shaped.

7. The device of claim 2, wherein said valve actuator means may be actuated manually.