Microfabricated cell sorter for chemical and biological materials

• US 6,540,895 B1
• Filed: 05/21/1999
• Issued: 04/01/2003
• Est. Priority Date: 09/23/1997
• Status: Expired due to Term

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Arnold, Frances H., Fu, Anne Y., Spence, Charles F., Quake, Stephen R.
• Primary Examiner(s): Warden, Jill
• Assistant Examiner(s): STARSIAK, JOHN S
• Application Number:
  US09/325,667
• Time in Patent Office: 1,411 Days
• Field of Search: 204/450, 204/451, 204/452, 204/453, 204/600, 204/601, 204/602, 204/603, 204/604, 204/547, 204/643, 435/283.1, 435/286.1, 435/286.5, 435/286.6, 435/288.4, 435/288.5
• US Class Current: 204/450
• CPC Class Codes: B01L 2200/0647 Handling flowable solids, e.g. microscopic beads, cells, particles
• CPC Class Codes: B01L 2200/0652 Sorting or classification of particles or molecules
• CPC Class Codes: B01L 2300/0654 Lenses; Optical fibres
• CPC Class Codes: B01L 2300/0816 Cards, e.g. flat sample carriers usually with flow in two horizontal directions
• CPC Class Codes: B01L 2300/0864 comprising only one inlet and multiple receiving wells, e.g. for separation, splitting
• CPC Class Codes: B01L 2300/123 Flexible; Elastomeric
• CPC Class Codes: B01L 2400/0406 capillary forces
• CPC Class Codes: B01L 2400/0415 electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 2400/0418 electro-osmotic flow [EOF]
• CPC Class Codes: B01L 2400/0421 electrophoretic flow
• CPC Class Codes: B01L 2400/0424 Dielectrophoretic forces
• CPC Class Codes: B01L 2400/0454 radiation pressure, optical tweezers
• CPC Class Codes: B01L 2400/0481 squeezing of channels or chambers
• CPC Class Codes: B01L 2400/0484 Cantilevers
• CPC Class Codes: B01L 2400/0487 fluid pressure, pneumatics
• CPC Class Codes: B01L 2400/0655 pinch valves
• CPC Class Codes: B01L 3/502707 characterised by the manufacture of the container or its components by shaping or joining plastic parts B29C59/00, B29C65/00; by laminating B32B37/00; manufacture of microstructural devices in general B81C
• CPC Class Codes: B01L 3/502738 characterised by integrated valves microvalves F16K99/0001
• CPC Class Codes: B01L 3/502761 specially adapted for handling suspended solids or molecules independently from the bulk fluid flow, e.g. for trapping or sorting beads, for physically stretching molecules investigating characteristics of particles G01N15/00
• CPC Class Codes: G01N 15/14 Optical investigation techniques, e.g. flow cytometry
• CPC Class Codes: G01N 15/149 : specially adapted for sorting particles, e.g. by their size or optical properties

Abstract

The invention provides a microfabricated device for sorting cells based on a desired characteristic, for example, reporter-labeled cells can be sorted by the presence or level of reporter on the cells. The device includes a chip having a substrate into which is microfabricated at least one analysis unit. Each analysis unit includes a main channel, having a sample inlet channel, typically at one end, and a detection region along a portion of its length. Adjacent and downstream from the detection region, the main channel has a discrimination region or branch point leading to at least two branch channels. The analysis unit may further include additional inlet channels, detection points, branch points, and branch channels as desired. A stream containing cells is passed through the detection region, such that on average one cell occupies the detection region at a given time. The cells can be sorted into an appropriate branch channel based on the presence or amount of a detectable signal such as an optical signal, with or without stimulation, such as exposure to light in order to promote fluorescence.

Claims

1. A method for sorting a fluid mixture of cells, which method comprises:

(a) providing the mixture of cells to a main channel of a microfabricated substrate, wherein the main channel is in fluid communication with at least two downstream branch channels which meet at a junction;

(b) producing a flow of fluid in the channel;

(c) interrogating each cell for a predetermined characteristic as it passes a detection region associated with the main channel; and

(d) directing the flow of each cell into a selected branch channel according to the results of the interrogation,

wherein the width and height of each channel is at least about two times as large as the diameter of the largest cell in the mixture of cells.

2. A method according to claim 1 in which the microfabricated substrate comprises a silicone elastomer.

3. A method according to claim 2 wherein the silicone elastomer comprises PolyDiMethylSiloxane (PDMS).