System and method for programmable illumination pattern generation

• US 20040072372A1
• Filed: 07/21/2003
• Published: 04/15/2004
• Est. Priority Date: 04/25/1996
• Status: Active Grant

• Current Assignee: Chiu W.O. Chau, Michael Seul
• Original Assignee: Chiu W.O. Chau, Michael Seul
• Inventors: Seul, Michael, Chau, Chiu Wo
• Granted Patent: US 7,390,676 B2
• Time in Patent Office: Days
• US Class Current: 436/523
• CPC Class Codes: B01J 19/0046 Sequential or parallel reactions, e.g. for the synthesis of polypeptides or polynucleotides; Apparatus and devices for combinatorial chemistry or for making molecular arrays synthesis methods per se C40B50/00
• CPC Class Codes: B01J 2219/00466 in a slurry
• CPC Class Codes: B01J 2219/00497 Features relating to the solid phase supports
• CPC Class Codes: B01J 2219/005 Beads
• CPC Class Codes: B01J 2219/00527 Sheets
• CPC Class Codes: B01J 2219/00572 Chemical means
• CPC Class Codes: B01J 2219/00585 Parallel processes
• CPC Class Codes: B01J 2219/00596 Solid-phase processes
• CPC Class Codes: B01J 2219/00648 by the use of solid beads
• CPC Class Codes: B01J 2219/00653 the compounds being bound to electrodes embedded in or on the solid supports
• CPC Class Codes: B01J 2219/00659 Two-dimensional arrays
• CPC Class Codes: B01J 2219/00677 Ex-situ synthesis followed by deposition on the substrate
• CPC Class Codes: B01J 2219/00713 Electrochemical synthesis
• CPC Class Codes: B01J 2219/00722 Nucleotides
• CPC Class Codes: B01J 2219/00725 Peptides
• CPC Class Codes: B01L 2200/0652 Sorting or classification of particles or molecules
• CPC Class Codes: B01L 2200/0663 Stretching or orienting elongated molecules or particles
• CPC Class Codes: B01L 2200/0668 Trapping microscopic beads
• CPC Class Codes: B01L 2300/0819 Microarrays; Biochips
• CPC Class Codes: B01L 2300/089 Virtual walls for guiding liquids
• CPC Class Codes: B01L 2400/0415 : electrical forces, e.g. electrokinetic
• CPC Class Codes: B01L 2400/0454 : radiation pressure, optical tweezers
• CPC Class Codes: B01L 2400/086 : using baffles or other fixed flow obstructions
• 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 3/502753 : characterised by bulk separation arrangements on lab-on-a-chip devices, e.g. for filtration or centrifugation separation in general B01D; microapparatus for analysis using electrophoresis G01N27/44791; sample preparation G01N1/28
• 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: B01L 3/502792 : for moving individual droplets on a plate, e.g. by locally altering surface tension
• CPC Class Codes: C12Q 1/6825 : Nucleic acid detection involving sensors
• CPC Class Codes: C12Q 1/6837 : using probe arrays or probe chips C12Q1/6874 takes precedence
• CPC Class Codes: C12Q 2563/155 : Particles of a defined size, e.g. nanoparticles
• CPC Class Codes: C12Q 2565/501 : being an array of oligonucleotides
• CPC Class Codes: C12Q 2565/607 : being a sensor, e.g. electrode
• CPC Class Codes: C40B 40/00 : Libraries per se, e.g. arrays, mixtures
• CPC Class Codes: C40B 60/10 : for identifying library members
• CPC Class Codes: G01N 15/0266 : with electrical classification
• CPC Class Codes: G01N 15/149 : specially adapted for sorting particles, e.g. by their size or optical properties
• CPC Class Codes: G01N 2015/0288 : Sorting the particles
• CPC Class Codes: G01N 2030/0035 : electrical field
• CPC Class Codes: G01N 30/0005 : Field flow fractionation
• CPC Class Codes: G01N 33/54313 : the carrier being characterised by its particulate form
• CPC Class Codes: G02B 3/0012 : characterised by the manufacturing method
• CPC Class Codes: G02B 3/0056 : arranged along two different directions in a plane, e.g. honeycomb arrangement of lenses G02B3/0043 takes precedence; miniaturised objectives for electronic devices employing wafer level optics G02B13/0085
• CPC Class Codes: H05H 3/04 : Acceleration by electromagnetic wave pressure
• CPC Class Codes: Y10T 436/25125 : Digestion or removing interfering materials

Abstract

A method and apparatus for the manipulation of colloidal particulates and biomolecules at the interface between an insulating electrode such as silicon oxide and an electrolyte solution. Light-controlled electrokinetic assembly of particles near surfaces relies on the combination of three functional elements: the AC electric field-induced assembly of planar aggregates; the patterning of the electrolyte/silicon oxide/silicon interface to exert spatial control over the assembly process; and the real-time control of the assembly process via external illumination. The present invention provides a set of fundamental operations enabling interactive control over the creation and placement of planar arrays of several types of particles and biomolecules and the manipulation of array shape and size. The present invention enables sample preparation and handling for diagnostic assays and biochemical analysis in an array format, and the functional integration of these operations. In addition, the present invention provides a procedure for the creation of material surfaces with desired properties and for the fabrication of surface-mounted optical components. The invention is also for a system and method for programmable illumination pattern generation, including a novel method and apparatus to generate patterns of illumination and project them onto planar surfaces or onto planar interfaces such as the interface formed by an electrolyte-insulator-semiconductor (EIS), e.g., as described herein. This enables the creation of patterns or sequences of patterns using graphical design or drawing software on a personal computer and the projection of said patterns, or sequences of patterns (“time-varying patterns”), onto the interface using a liquid crystal display (LCD) panel and an optical design which images the LCD panel onto the surface of interest. The use of the LCD technology provides flexibility and control over spatial layout, temporal sequences and intensities (“gray scales”) of illumination patterns. The latter capability permits the creation of patterns with abruptly changing light intensities or patterns with gradually changing intensity profiles.

Claims

1. A process of spatially encoding a planar assembly of particles formed on a substrate by sequential injection of a multiplicity of groups of particles of at least one type, said process comprising:

providing a substrate comprising a light-sensitive planar electrode, the light-sensitive electrode being aligned with another planar electrode in substantially parallel arrangement, with said electrodes being separated by a gap, and the gap containing an electrolyte solution which is in contact with said electrodes;

placing a group of at least one type of particles selected from a reservoir containing said at least one type of particles into the electrolyte solution so as to confine said injected particles into a first segment of the light-sensitive electrode delineated by a first illumination pattern on said light-sensitive electrode;

translocating said confined particles to a second segment of the light-sensitive electrode delineated by a second illumination pattern on said light-sensitive electrode; and

merging said particles with any pre-existing planar assembly of particles previously formed in said second segment of the light-sensitive electrode.

2. The process of claim 1, further comprising recording an image showing said translocated particles of said groups of particles in their final positions within said second segment.

3. The process of claim 2, wherein the first illumination pattern and the second illumination pattern are provided by using a programmable illumination pattern generator, said method further comprising reiterating the placing, translocating, merging and recording steps n times, wherein n is an integer from zero to about 10,000.

4. A process of decoding a planar assembly of particles encoded according to the process of claim 3, said decoding process comprising:

cross-correlating an image of the planar assembly with each of the images recorded at the completion of each placing, translocating and merging step.

5. A self-tuning filter comprising:

a light-sensitive planar electrode that is aligned with another planar electrode in substantially parallel arrangement, with said electrodes being separated by a gap, and the gap containing an electrolyte solution which is in contact with said electrodes and which contains colloidal particles, wherein said particles are assembled in a planar array on the light-sensitive electrode, said array being composed so as to partially block incident light that controls array assembly in response to an electric field, and wherein the lateral density of said array self-adjusts in response to transmitted light intensity;

means for adjusting frequency of said applied electric field to a value lower than the characteristic dielectric relaxation frequency of said particles;

means for defining an illuminated area on said light-sensitive electrode; and

means for adjusting illumination intensity so as to induce assembly of said particles within the illuminated area.

6. The self-tuning filter of claim 5, wherein self-adjustment determines an optimal lateral density on attaining equilibrium which correlates with the transmitted light intensity of the frequency of the applied electric field.

7. A fractionation device for spatially separating and sorting a mixture of particles on a substrate comprising:

a substrate comprising a light-sensitive planar electrode, the light-sensitive electrode being aligned with another planar electrode in substantially parallel arrangement, with said electrodes being separated by a gap, and the gap containing an electrolyte solution which is in contact with said electrodes and which contains colloidal particles suspended in the electrolyte solution, said particles comprising a multiplicity of particle types exhibiting a differential frequency-dependent response to an applied electric field in accord with the respective characteristic frequency of each said particle type;

means for applying a time-varying voltage between said electrodes so as to generate a time-varying electric field and to induce the motion of said particles;

a means for adjusting frequency to a value less than the characteristic frequency of at least one particle type; and

a light-control component permitting illumination of a predetermined segment of the substrate with a predetermined intensity so as to induce collection into said illuminated segment of substantially all said particles of said at least one particle type having respective characteristic frequencies exceeding the frequency of the applied field.

8. The fractionation device of claim 7, wherein the particles are cells.

9. The fractionation device of claim 7, wherein the light-control component is a programmable illumination pattern generator.

10. The fractionation device of claim 7, wherein the particles may be collected into an illuminated segment being laterally scanned or reconfigured.

11. The fractionation device of claim 7, wherein the particles are separated based on differential-frequency response determined by particle size or by particle chemical composition.

12. A flow control device for generating fluid flow comprising:

a light-sensitive planar electrode that is aligned with another planar electrode in substantially parallel arrangement, with said electrodes being separated by a gap, and the gap containing a fluid medium that is in contact with said electrodes;

means for applying a time-varying voltage between said electrodes so as to generate a time-varying electric field and to induce said fluid medium to undergo lateral flow;

means for adjusting voltage magnitude and frequency to preselected values to control flow velocity; and

a light-control component permitting illumination of a designated segment of the light-sensitive electrode, the combination of said time-varying electric field and illumination producing transverse fluid flow in accordance with the contour shape of the illuminated segment, said flow having a velocity component everywhere directed parallel to the surface and normal to the contour.

13. The flow control device of claim 12, said device being operated to generate a sequence of flow configurations.

14. The flow control device of claim 12, said device being operated so as to produce local flow fields in a configuration affecting the mixing of the fluid medium.