Magneto-optical bio-discs and systems including related methods

• US 20040248093A1
• Filed: 11/27/2002
• Published: 12/09/2004
• Est. Priority Date: 11/27/2000
• Status: Abandoned Application

• Current Assignee: Nagaoka & Co., Ltd.
• Original Assignee: Nagaoka & Co., Ltd.
• Inventors: Coombs, James Howard, Valencia, Ramoncito Magpantay, Phan, Brigitte Chau
• Application Number:
  US10/307,263
• Publication Number:
  US 20040248093A1
• Time in Patent Office: Days
• US Class Current: 435/6
• CPC Class Codes: B01L 2200/0668 Trapping microscopic beads
• 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 2400/0409 centrifugal forces
• CPC Class Codes: B01L 2400/043 magnetic forces
• 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 33/54326 Magnetic particles
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing
• 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

Abstract

The present invention relates in general to molecular and cellular biomagnetic assays and, in particular, to molecular and cellular biomagnetic assays conducted on magneto-optical bio-discs. The invention further relates to magneto-optical bio-disc systems including the magneto-optical bio-discs and MO drives. More specifically, but without restriction to the particular embodiments hereinafter described in accordance with the best mode of practice, this invention relates to biomagnetic methods, including immunomagnetic methods, for detection and selective manipulation of specific target cells in cell populations and solutions of cell populations, using magnetic particles or beads, and to magnetically guided neurite growth, nerve regeneration, and magnetically formed neural networks using the MOBDS.

Claims

1. A magneto-optical bio-disc for use in bio-magnetic assays, said bio-disc comprising:

a substrate having a center and an outer edge;

a magneto-optic stack associated with said substrate; and

one or more magnetic domains formed on said magneto-optic stack, said one or more magnetic domains employed to bind and release bio-magnetic particles.

2. The magneto-optical bio-disc according to claim 1 wherein said bio-magnetic particles are paramagnetic beads having attached thereto a binding agent.

3. The magneto-optical bio-disc according to claim 2 wherein said binding agent is selected from the group comprising an antigen, an antibody, a ligand, a receptor, biotin, streptavidin, DNA fragments, and RNA fragments.

4. The magneto-optical bio-disc according to claim 1 wherein said one or more magnetic domains are selectively formed within said center and outer edge of said substrate using a magneto-optical disc drive.

5. The magneto-optical bio-disc according to claim 4 wherein said one or more magnetic domains are selectively erased using said magneto-optical disc drive.

6. The magneto-optical bio-disc according to either claim 4 or 5 wherein said one or more magnetic domains are formed and erased to thereby allow said bio-magnetic particles to be selectively bound and released.

7. The magneto-optical bio-disc according to claim 6 wherein said magneto-optical disc drive is used to read and detect features located in said magnetic domains.

8. The magneto-optical bio-disc according to claim 7 further comprising a channel layer associated with said substrate, said channel layer having cut-out portions to form fluidic circuits.

9. The magneto-optical bio-disc according to claim 8 further comprising a cap portion associated with said channel layer.

10. The magneto-optical bio-disc according to claim 9 wherein said fluidic circuits include an inlet port, a mixing chamber, a separation chamber, one or more testing chambers, and a vent port, all of which being in fluid communication with each other.

11. The magneto-optical bio-disc according to claim 10 wherein said one or more testing chambers are pre-loaded with a test solution having a test agent.

12. A method of using the magneto-optical bio-disc of claim 11 to detect, quantify, and test target cells for drug sensitivity, said method of using comprising the steps of:

providing a sample of cells;

loading said sample into said mixing chamber through said inlet port;

providing bio-magnetic particles having attached thereto binding agents specific for surface markers on the surface of target cells in the sample;

loading said bio-magnetic particles into said mixing chamber;

incubating said sample and bio-magnetic particles for a sufficient time to allow binding of the binding agents with the surface markers on the target cells in the sample to thereby create labeled cells;

loading said magneto-optical bio-disc into said magneto-optical disc drive;

forming magnetic domains in pre-determined locations within said separation chamber;

rotating said magneto-optical bio-disc to move said sample and bio-magnetic particles into said separation chamber;

allowing said bio-magnetic particles and labeled cells to bind to said magnetic domains within said separation chamber; and

scanning said separation chamber with a beam of electromagnetic radiation to determine whether magnetic domains contain labeled cells.

13. The method according to claim 12 further comprising the steps of:

quantitating the number of labeled cells bound in said magnetic domains;

erasing selectively said magnetic domains having labeled cells bound thereto, thereby selectively releasing the labeled cells;

guiding magnetically said labeled cells into said one or more test chambers by sequentially erasing and forming said magnetic domains to move a pre-determined number of labeled cells into the one or more test chambers;

incubating said labeled cells with said test agent; and

scanning said test chamber with beam of electromagnetic radiation to determine the number of live and apototic cells and thereby determine the sensitivity of the cells to said test agent.

14. A method of using the magneto-optical bio-disc of claim 9 to create neural networks within a biological matrix in said fluidic circuits, said method of using comprising the steps of:

forming said biological matrix in said fluidic circuits;

providing neurons having dendrites and axons into said biological matrix, said neurons having magnetic particles incorporated therein;

loading said magneto-optical bio-disc into said magneto-optical disc drive;

writing and erasing magnetic domains within said fluidic circuits to cause said dendrites and axons of said neurons to grow toward each other; and

allowing interaction between said neurons through said dendrites and axons thereby forming said neural networks magnetically controlled by said magnetic domains.

15. The magneto-optical bio-disc of claim 11.

16. A magneto-optical bio-disc system for use in magneto-optical bio-magnetic assays, said system comprising:

a magneto-optical bio-disc comprising;

a substrate having a magneto-optic stack; and

one or more magnetic domains formed within in said substrate, said one or more magnetic domains employed to bind and release bio-magnetic particles; and

a magneto-optical disc drive comprising;

a light source for directing light to the disc, said light source further used to form or erase said one or more magnetic domains; and

a detector for detecting light reflected from or transmitted through the disc and providing a signal.

17. The magneto-optical bio-disc system according claim 16 further comprising a processor for utilizing said signal to count items bound to said one or more magnetic domains.

18. The magneto-optical bio-disc system according to claim 17.

19. A method of making a magneto-optical bio-disc, said method comprising the steps of:

providing a substrate having a center, an outer edge, and one or more magneto optical stacks;

forming one or more magnetic domains within said center and outer edge; and

forming an analysis chamber in fluid communication with said one or more magnetic domains.

20. The method according to claim 19 further comprising the step of forming a mixing chamber in fluid communication with the analysis chamber.

21. The method according to claim 19 further comprising the step of forming a biological matrix within said analysis chamber.

22. The method according to claim 20 further comprising the step of depositing a plurality of bio-magnetic particles in said mixing chamber, each of said bio-magnetic particles including a binding agent.

23. The method according to claim 22 further comprising the step of designating an input site associated with said mixing chamber, said input site implemented to receive a sample of cells to be tested for the presence of any target cells.

24. The method according to either claim 21 or 23 further comprising the step of encoding information on an information layer associated with the substrate, said encoded information being readable by a disc drive assembly to control rotation of the disc.

25. The method according to claim 24 further comprising the step of forming a test chamber in fluid communication with said analysis chamber.

26. The method according to claim 25 further comprising the step of filling said test chamber with a test agent.

27. A method of using the magneto-optical bio-disc made according to claim 21 to create neural networks within the biological matrix in said fluidic circuits, said method of using comprising the steps of:

providing neurons having dendrites and axons into said biological matrix;

incorporating magnetic particles into said neurons;

loading said magneto-optical bio-disc into a magneto-optical disc drive;

erasing and forming said one or more magnetic domains within said analysis chamber to cause said dendrites and axons of said neurons to grow toward each other; and

allowing interaction between said neurons through said dendrites and axons thereby forming said neural networks magnetically controlled by said magnetic domains.

28. A method of using the magneto-optical bio-disc made according to claim 26 to detect, quantify, and test said any target cells in said sample of cells for drug sensitivity, said method of using comprising the steps of:

loading said sample into said mixing chamber through said input site;

incubating said sample and bio-magnetic particles for a sufficient time to allow binding of the binding agents with surface markers on the target cells in the sample to thereby create labeled cells;

loading said magneto-optical bio-disc into a magneto-optical disc drive;

forming magnetic domains in pre-determined locations within said analysis chamber;

rotating said magneto-optical bio-disc to move said sample and bio-magnetic particles into said analysis chamber;

allowing said bio-magnetic particles and labeled cells to bind to said magnetic domains within said analysis chamber; and

scanning said analysis chamber with a beam of electromagnetic radiation to determine whether magnetic domains contain labeled cells.

29. The method according to claim 28 further comprising the steps of:

quantitating the number of labeled cells contained in said magnetic domains;

erasing selectively said magnetic domains having labeled cells bound thereto, thereby selectively releasing the labeled cells;

guiding magnetically said labeled cells into said test chamber by sequentially erasing and forming said magnetic domains to move a pre-determined number of labeled cells into the test chamber;

incubating said labeled cells with said test agent; and

scanning said test chamber with beam of electromagnetic radiation to determine the number of live and apototic cells and thereby determine the sensitivity of the cells to said test agent.