CA2985652C

Rapid methods for the extraction of nucleic acids from biological samples

Abstract

The invention is directed to compositions and methods for rapidly and efficiently extracting nucleic acids and/or targeted nucleic acids sequences from biological samples. The methods comprise combining the sample with a buffer and magnetic silicon beads and concentrating the beads with a magnet or other electrical field. Liquid may be removed, or not, and an alkaline buffer is added followed by magnetic carboxy beads in a binding buffer so that nucleic acids transfer to the carboxy beads, which can be easily and quickly isolated once again with a magnet. Total nucleic acid extraction is greatly enhanced. Extracted nucleic acids can be analyzed, for example, by PCR wherein the nucleic acids can be identified and characterized. Carboxy beads may also contain a ligand so as to target specific nucleic acid sequences. The invention is also directed to kits comprising the tools and compositions for performing the methods of the invention.

CA2985652C, drawing sheet 1
Sheet 1 of 19

Term

9.6 yearsleft in the term

Expires 12 May 2036.

  1. Priority and filed
  2. Granted
  3. Today
  4. Expires

61 claims: 5 independent, 56 dependent

  1. 1
    THE EMBODIMENTS OF THE INVENTION FOR WHICH AN EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:1. A method of extracting nucleic acids from a biological sample containing cells and/or microorganisms comprising: adding a matrix material and a buffer to the biological sample, wherein the matrix material binds to nucleic acids of the sample;isolating matrix material bound to nucleic acids of the sample;adding an intermediate buffer to the nucleic acid bound matrix, wherein the intermediate buffer promotes a release of nucleic acids from the matrix material to form a mixture;adding a chemically modified magnetic matrix material and a binding buffer to the mixture wherein the chemically modified matrix material comprises a ligand that binds to a specific nucleic acid sequence;exposing the mixture to a magnetic field to concentrate the magnetic matrix material bound to the specific nucleic acid sequence;and adding an extraction buffer to the concentrated magnetic matrix material wherein the specific nucleic acid sequence is extracted from the magnetic matrix material.
  2. 22
    23. The method of claim 22, wherein the conventional extraction procedure is a silica spin column extraction.
  3. 23
    24. A method of extracting nucleic acids from a biological sample containing cells and/or microorganisms comprising:combining the biological sample with magnetic silicon dioxide beads and a lysis buffer to form a solution, wherein the beads bind to nucleic acids of the sample;exposing the solution to a magnetic field and removing liquid to concentrate the beads;adding an alkaline buffer to the concentrated magnetic beads to form a mixture, wherein the alkaline buffer causes the release of nucleic acids from the silicon dioxide beads;adding carboxy-modified magnetic beads in a binding buffer to the mixture wherein the carboxy-modified magnetic beads bind to a predetermined nucleic acid sequence;exposing the mixture to a magnetic field and removing liquid to isolate the carboxy-modified magnetic beads bound to the predetermined nucleic acid sequence;and eluting the predetermined nucleic acid sequences from the carboxy-modified magnetic beads using purified water and/or a Tris-EDTA buffer.
  4. 24
    25. The method of claim 24, wherein the lysis buffer comprises a chaotrope, a detergent, a reducing agent, a buffering agent, and a chelator, together at a pH of about 6 to about 8.
  5. 29
    30. The method of claim 29, wherein the conventional extraction procedure is a silica spin column extraction.
  6. 31
    32. A kit for extracting nucleic acids from a biological sample containing cells and/or microorganisms comprising:a solution that comprises a matrix material and a buffer;an intermediate buffer with a pH above 7;and carboxy-modified magnetic beads in a binding buffer, wherein the carboxymodified magnetic beads bind to a specific nucleic acid sequence.
  7. 32
    33. The kit of claim 32, wherein the buffer comprises a chaotrope, a detergent, a reducing agent, a buffering agent and a chelator, together at a pH of about 6 to about 8.
  8. 33
    34. The kit of claim 33, wherein the buffer lyses cells, inactivates nucleases, stabilizes nucleic acids, and sterilizes the sample.
  9. 42
    43. A method of extracting nucleic acids from a biological sample containing cells and/or microorganisms comprising:combining the biological sample with a buffer to form a mix;combining the mix with magnetic matrix material to form a solution, wherein neither the buffer or matrix material disrupt the cells and/or microorganisms of the biological sample and the magnetic matrix material binds to nucleic acids of the biological sample other than those present within the cells and/or microorganisms;CA 2985652 2019-08-15 exposing the solution to a magnetic field and removing liquid to concentrate the magnetic matrix material;adding an alkaline buffer to the concentrated magnetic matrix material to form a mixture, wherein the alkaline buffer causes the release of nucleic acids from the magnetic matrix material;adding carboxy-modified magnetic beads in a binding buffer to the mixture wherein the carboxy-modified magnetic beads bind to specific nucleic acid sequences;exposing the mixture to the magnetic field and removing liquid to isolate the carboxy-modified magnetic beads bound to the specific nucleic acid sequences;and eluting the specific nucleic acid sequences from the carboxy-modified magnetic beads using purified water and/or a Tris-EDTA buffer.
  10. 43
    44. The method of claim 43, wherein the buffer comprises a chaotrope, a detergent, a reducing agent, a buffering agent, and a chelator, together at a pH of about 6 to about 8.
  11. 45
    46. The method of claim 45, wherein the biological sample combined with the buffer is stored for between about 2 days to about 20 days before combining with the magnetic matrix material.
  12. 52
    53. The method of claim 52, wherein identifying comprises PCR.
  13. 58
    59. The method of claim 58, wherein the pathogen is a virus, a bacterium, a parasite or a fungus.
  14. 61
    62. A method of extracting nucleic acids from a biological sample containing cells and/or microorganisms comprising:combining the biological sample with a buffer to form a mix;combining the mix with magnetic matrix material to form a solution, wherein neither the buffer or matrix material disrupt the cells and/or microorganisms of the biological sample and the magnetic matrix material binds to nucleic acids of the biological sample other than those present within the cells and/or microorganisms;exposing the solution to a magnetic field and removing liquid to concentrate the magnetic matrix material;adding an alkaline buffer to the concentrated magnetic matrix material to form a mixture, wherein the alkaline buffer causes the release of nucleic acids from the magnetic matrix material;adding carboxy-modified magnetic beads in a binding buffer to the mixture wherein the carboxy-modified magnetic beads bind to a specific nucleic acid sequences;CA 2985652 2019-08-15 exposing the mixture to a magnetic field and removing liquid to isolate the carboxy-modified magnetic beads bound to the specific nucleic acid sequences;eluting the specific nucleic acid sequences from the carboxy-modified magnetic beads using purified water and/or a Tris-EDTA buffer;and identifying the specific nucleic acid sequences by PCR, wherein the presence of the specific nucleotide sequence in the biological sample is indicative of the presence of a cancer or a pathogen.