CN110904205A - Nucleic acid molecule analysis and identification method - Google Patents

Nucleic acid molecule analysis and identification method Download PDF

Info

Publication number
CN110904205A
CN110904205A CN201911208274.9A CN201911208274A CN110904205A CN 110904205 A CN110904205 A CN 110904205A CN 201911208274 A CN201911208274 A CN 201911208274A CN 110904205 A CN110904205 A CN 110904205A
Authority
CN
China
Prior art keywords
nucleic acid
acid molecule
nanopore
electrode
tag
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
CN201911208274.9A
Other languages
Chinese (zh)
Inventor
贾晓轻
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to CN201911208274.9A priority Critical patent/CN110904205A/en
Publication of CN110904205A publication Critical patent/CN110904205A/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12QMEASURING OR TESTING PROCESSES INVOLVING ENZYMES, NUCLEIC ACIDS OR MICROORGANISMS; COMPOSITIONS OR TEST PAPERS THEREFOR; PROCESSES OF PREPARING SUCH COMPOSITIONS; CONDITION-RESPONSIVE CONTROL IN MICROBIOLOGICAL OR ENZYMOLOGICAL PROCESSES
    • C12Q1/00Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions
    • C12Q1/68Measuring or testing processes involving enzymes, nucleic acids or microorganisms; Compositions therefor; Processes of preparing such compositions involving nucleic acids
    • C12Q1/6869Methods for sequencing

Abstract

A method for the analytical identification of nucleic acid molecules for identifying tag-conjugated nucleic acid molecules, comprising: (1) flowing the tag-coupled nucleic acid molecule through a first fluid channel having a width greater than the tag toward the nanopore; (2) the diameter of the nanopore is smaller than the diameter of the tag; measuring a change in current of an electrode proximate to the nanopore as the nucleic acid molecule flows into the nanopore; determining the sequence of the nucleic acid molecule from the change in current; (3) after the measurement is completed, the nucleic acid molecule coupled with the label is made to flow out of the nucleic acid molecule analysis and identification system through an outflow path without overlapping with an inflow path of the nucleic acid molecule above the nanopore.

Description

Nucleic acid molecule analysis and identification method
Technical Field
The invention relates to a nucleic acid molecule analysis and identification method.
Background
Nanopores are nanoscale pores embedded on biological membranes or fabricated on solid state membranes. When a voltage is applied across the nanopore, a field is formed in and around the nanopore. Ions, DNA, RNA, polypeptides, and other biological macromolecules typically carry a surface charge that passes through the nanopore under the influence of an electric field force as they diffuse into the vicinity of the nanopore. By adopting the method of detecting the current passing through the nanopore, when a substance passes through the nanopore, the change of the ionic current can be caused, so that the information of the molecules of the substance to be detected can be obtained.
In DNA sequencing, when DNA passes through a nanopore, different signals are generated through the nanopore due to the different chemical properties of each base, and the base sequence of DNA is obtained by the difference of the signals, so that rapid sequencing can be realized. However, the DNA molecule is too fast to pass through the hole, and the current change generated when a single base passes through the nanopore is difficult to capture. The main technical means in the prior art is to reduce the perforation speed of nucleic acid molecules by changing voltage or solution, such as the technical scheme proposed by the patent of CN102621214A at Beijing university, the method can improve time resolution, but the requirement of determining the current change of each base passing through a nanopore is high, and the requirement of sensitivity of the sensor is high.
CN107110817A and CN109863391A propose methods for identifying specific sequences of nucleic acid molecules, wherein a tag with a diameter larger than that of a nanopore is coupled to one end of a nucleic acid molecule, and when the tag is blocked by the nanopore, the current of an electrode near the nanopore is changed, and the specific sequence coupled to the tag is determined through the current change. However, in this method, the nanopore is blocked after it is exposed to the label, it is necessary to separate the label from the nucleic acid molecule or to apply an opposite voltage to separate the label from the nanopore in a direction opposite to the flow direction. The present invention provides, as an improvement of CN107110817A, a method for analyzing and identifying nucleic acid molecules, which can improve detection efficiency.
Disclosure of Invention
The present invention provides a method for the analytical identification of nucleic acid molecules, for identifying tag-conjugated nucleic acid molecules, comprising: (1) flowing the tag-coupled nucleic acid molecule through a first fluid channel having a width greater than the tag toward the nanopore; (2) the diameter of the nanopore is smaller than the diameter of the tag; measuring a change in current of an electrode proximate to the nanopore as the nucleic acid molecule flows into the nanopore; determining the sequence of the nucleic acid molecule from the change in current; (3) after the measurement is completed, the nucleic acid molecule coupled with the label is made to flow out of the nucleic acid molecule analysis and identification system through an outflow path without overlapping with an inflow path of the nucleic acid molecule above the nanopore.
Preferably, the time at which the currently tagged nucleic acid molecule exits the nucleic acid molecule analytical identification system at step (3) partially overlaps with the time at which the next tagged nucleic acid molecule flows through the first fluidic channel to the nanopore at step (1).
The outflow path includes a second fluid passage having a width greater than the label diameter.
Alternatively, the nucleic acid molecule analysis and identification method identifies a nucleic acid molecule to which a tag is coupled by a nucleic acid molecule analysis and identification system comprising: a first fluid channel having a first width, the first width being greater than the label diameter; a nanopore having a diameter of a second width, the second width being less than the tag diameter, a first electrode disposed below the nanopore; further comprising a second fluid channel having a third width; the first fluid channel is positioned on the side of the nanopore, a second electrode with unchanged polarity is arranged on one side of the first fluid channel opposite to the nanopore, and the polarity of the second electrode is opposite to that of the first electrode; the second fluid channel is located above the nanopore, the third width being greater than the tag diameter; the second fluid channel is provided with a third electrode; the first electrode is not energized when the tag-coupled nucleic acid molecule flows toward the front of the first channel of the nanopore and when the tag-coupled nucleic acid molecule exits the nanopore; the first electrode has an opposite polarity to the second electrode when the tag-coupled nucleic acid molecule flows to the back of the first fluidic channel of the nanopore; the third electrode has a polarity opposite to the second electrode when the tagged nucleic acid molecule flows toward the front of the first fluid channel of the nanopore and when the tagged nucleic acid molecule exits the nanopore; the third electrode is not energized when the tag-coupled nucleic acid molecule flows to the back of the first fluid channel of the nanopore.
Preferably, the first fluid channel is at an angle of about 90 degrees to the nanopore.
Preferably, the label is fluorescein imide or hexachlorofluorescein.
Preferably, the nanopore is a biological nanopore or a solid state nanopore.
Preferably, the tag is coupled to the nucleic acid molecule via a linker.
Preferably, the tag is a polypeptide.
Preferably, the tag is coupled to the end of the nucleic acid molecule.
Preferably, the nucleic acid molecule analysis and identification system is used for determining a nucleic acid sequence in a sample.
Preferably, the nucleic acid molecule analysis and identification system determines the sequence of the nucleic acid in the sample based on the current passing through the first electrode.
Preferably, the nucleic acid molecule is deoxyribonucleic acid (DNA) or ribonucleic acid (RNA).
Preferably, the sample is from a bodily fluid.
Alternatively, the nucleic acid molecule analysis and identification method identifies a nucleic acid molecule to which a tag is coupled by a nucleic acid molecule analysis and identification system comprising: a first fluid channel having a first width, the first width being greater than the label diameter; a nanopore having a diameter of a second width, the second width being less than the tag diameter, a first electrode disposed below the nanopore; further comprising a second fluid channel having a third width; the first fluid channel is positioned on the side of the nanopore, a second electrode with unchanged polarity is arranged on one side of the first fluid channel opposite to the nanopore, and the polarity of the second electrode is opposite to that of the first electrode; the second fluid channel is located above the nanopore, the third width being greater than the tag diameter; the second fluid channel comprises a first channel extending upwards and a second channel in the opposite direction of the first flow channel, the third electrode is arranged at the top end of the junction of the first channel and the second channel, and a fourth electrode is arranged on the side, opposite to the third electrode, of the second channel; the first electrode is not energized when the tag-coupled nucleic acid molecule exits the nanopore in the first channel; setting the polarity of the first electrode to be opposite to that of the second electrode at other moments; the third electrode is configured to have a polarity opposite to the second electrode when the tag-coupled nucleic acid molecule exits the nanopore and is located in the first channel, to have a polarity the same as the second electrode when the tag-coupled nucleic acid molecule exits the nanopore and is located in the second channel, and to not be energized after the tag-coupled nucleic acid molecule exits the second channel; the fourth electrode is configured to have a polarity opposite to the second electrode when the tag-coupled nucleic acid molecule exits the nanopore in the second channel and is not energized after the tag-coupled nucleic acid molecule exits the second channel.
Preferably, the length of the second channel is greater than 1.5 times the length of the first channel.
Preferably, the first passage length is less than 1/2 of the first fluid passage length.
Preferably, the absolute value of the voltage of the third electrode is less than the absolute value of the voltage of the second electrode when the tag-coupled nucleic acid molecule exits the nanopore in the second channel.
Preferably, the label-coupled nucleic acid molecule leaves the nanopore without an overlapping portion of its path to the nanopore.
Preferably, the nucleic acid molecule analysis and identification system determines the sequence of the nucleic acid in the sample based on the current passing through the first electrode.
Drawings
FIG. 1 is a flow chart of the method for analyzing and identifying a nucleic acid molecule of the present invention
FIG. 2 is a schematic diagram of a first embodiment of the nucleic acid molecule analysis/identification system for carrying out the nucleic acid molecule analysis/identification method of the present invention.
FIG. 3 is a schematic view of a second embodiment of the nucleic acid molecule analysis/identification system for carrying out the nucleic acid molecule analysis/identification method of the present invention.
Detailed Description
In order to more clearly illustrate the technical solutions of the present invention, the present invention will be briefly described below by using embodiments, and it is obvious that the following description is only one embodiment of the present invention, and for those skilled in the art, other technical solutions can be obtained according to the embodiments without inventive labor, and also fall within the disclosure of the present invention.
The method for analyzing and identifying nucleic acid molecules of the present invention is used for identifying nucleic acid molecules coupled with labels in a sample, see fig. 1, and comprises the following steps: (1) flowing the tag-coupled nucleic acid molecule through a first fluid channel having a width greater than the tag toward the nanopore; (2) the diameter of the nanopore is smaller than the diameter of the tag; measuring a change in current of an electrode proximate to the nanopore as the nucleic acid molecule flows into the nanopore; determining the sequence of the nucleic acid molecule from the change in current; (3) after the measurement is completed, the labeled nucleic acid molecule is made to flow out of the nucleic acid molecule analysis and identification system through an outflow path which has no overlapping part with the inflow path of the nucleic acid molecule above the nanopore, wherein the currently labeled nucleic acid molecule is made to partially overlap with the next labeled nucleic acid molecule coupled in the step (1) at the time when the labeled nucleic acid molecule flows toward the nanopore through the first fluid channel in the step (3).
The method for analyzing and identifying nucleic acid molecules of the present invention identifies the labeled nucleic acid molecules by a nucleic acid molecule analyzing and identifying system, which includes a first fluid channel 10, a nanopore 20, a second fluid channel 30, a first electrode 40, a second electrode 50, and a third electrode 60, see fig. 2. The nucleic acid molecule is deoxyribonucleic acid (DNA) or ribonucleic acid (RNA), and the label is coupled with the specific nucleic acid molecule through a connecting body, and the label can be fluorescein imide or hexachlorofluorescein or polypeptide. The nucleic acid molecule analysis system determines the nucleic acid sequence of the corresponding specific nucleic acid molecule in the sample by detection of the tag.
The nanopore 20 is a biological nanopore or a solid state nanopore, the diameter of the nucleic acid molecule is smaller than the nanopore 20, and the diameter of the nanopore 20 is smaller than the diameter of the tag so that the tag-coupled nucleic acid molecule causes a change in electrode current near the nanopore 20 when the tag is blocked by the nanopore 20 as the nucleic acid molecule passes through the nanopore 20. The first fluidic channel 10 is located lateral to the nanopore 20, and has a first width greater than the label diameter. The angle between the first fluid channel 10 and the nanopore may be set to 60 degrees to 12 degrees, and preferably may be set to about 90 degrees. A first electrode 40 is disposed below the nanopore 20, a second electrode 50 with a constant polarity is disposed on the opposite side of the first fluid channel 10 from the nanopore 20, and the polarity of the second electrode 50 is opposite to that of the first electrode 40, so that the nucleic acid molecule can be driven to move from the second electrode 50 to the first electrode 40.
A second fluid channel 30 is located above the nanopore 20 having a third width greater than the label diameter. The second fluid channel 30 is provided with a third electrode 60 on a side opposite to the nanopore 20. The first electrode 40 is not energized when the tag-coupled nucleic acid molecule flows toward the front of the first channel 10 of the nanopore 20 and when the tag-coupled nucleic acid molecule exits the nanopore 20; the first electrode 40 has a polarity opposite to that of the second electrode 50 when the tag-coupled nucleic acid molecule flows toward the rear of the first fluid channel 10 of the nanopore 20; the polarity of the third electrode 60 is opposite to the second electrode 50 when the tag-coupled nucleic acid molecule flows to the front of the first fluid channel 10 of the nanopore 20 and when the tag-coupled nucleic acid molecule exits the nanopore 20; the third electrode 60 is not energized when the tag-coupled nucleic acid molecule flows to the rear of the first fluid channel 10 of the nanopore. Thus, the label of the labeled nucleic acid molecule coupled to it leaves the nanopore 20 without overlapping the path of the label of the labeled nucleic acid molecule coupled to it flowing to the nanopore 20; while the labeled nucleic acid molecule coupled to the plugged nanopore 20 is attracted by the electric field of the third electrode 60 to leave the nanopore 20 through the second fluid channel 30, the next labeled nucleic acid molecule coupled to the nanopore 20 is attracted by the electric field of the third electrode 60 to flow in front of the first fluid channel 10, and after the labeled nucleic acid molecule coupled to the nanopore 20 is discharged through the second fluid channel 30, the next labeled nucleic acid molecule coupled to the nanopore 20 is attracted by the electric field of the first electrode 40 to flow in the rear of the first fluid channel 10 for detection; thereby improving the detection efficiency compared with the prior art.
As a further improvement, the nucleic acid molecule analyzing and identifying system of the nucleic acid molecule analyzing and identifying method according to the preferred embodiment of the present invention is shown in fig. 3, and includes a first fluid channel 10, a nanopore 20, a second fluid channel 30, a first electrode 40, a second electrode 50, a third electrode 60, and a fourth electrode 70.
The nanopore 20 is a biological nanopore or a solid state nanopore, the diameter of the nucleic acid molecule is smaller than the nanopore 20, and the diameter of the nanopore 20 is smaller than the diameter of the tag so that the tag-coupled nucleic acid molecule causes a change in electrode current near the nanopore 20 when the tag is blocked by the nanopore 20 as the nucleic acid molecule passes through the nanopore 20. The first fluidic channel 10 is located lateral to the nanopore 20, and has a first width greater than the label diameter. The angle between the first fluid channel 10 and the nanopore may be set to 60 degrees to 12 degrees, and preferably may be set to about 90 degrees. A first electrode 40 is disposed below the nanopore 20, a second electrode 50 with a constant polarity is disposed on the opposite side of the first fluid channel 10 from the nanopore 20, and the polarity of the second electrode 50 is opposite to that of the first electrode 40, so that the nucleic acid molecule can be driven to move from the second electrode 50 to the first electrode 40.
The second fluid passage 30 is wider than the label and includes a first passage 31 extending upward and a second passage 32 in the opposite direction of the first fluid passage 10, 1/2 providing a length of the first passage 31 less than the length of the first fluid passage 10, the length of the second passage 32 being greater than 1.5 times the length of the first passage 31. The third electrode 60 is arranged at the top end of the junction of the first channel 31 and the second channel 32, and the fourth electrode 70 is arranged on one side of the second channel 32 opposite to the third electrode 60; preferably, the third electrode 60 and the first channel 31 form an angle of 45 degrees, and the third electrode 60 and the second channel 32 form an angle of 45 degrees.
The first electrode 40 is not energized when the tag-coupled nucleic acid molecule exits the nanopore 20 at the first channel 31; setting its polarity opposite to the second electrode 50 at the rest of the time; the third electrode 60 is configured to have a polarity opposite to that of the second electrode 60 when the labeled nucleic acid molecule exits the nanopore 20 and is located in the first channel 31, and configured to have a polarity identical to that of the second electrode 60 when the labeled nucleic acid molecule exits the nanopore 20 and is located in the second channel 32, and to have an absolute value of a voltage smaller than that of the second electrode, and to be not energized after the labeled nucleic acid molecule exits the second channel 32; the fourth electrode 70 is configured to have a polarity opposite the second electrode 50 when the tag-coupled nucleic acid molecule exits the nanopore 20 and is located in the second channel 32, and is not energized after the tag-coupled nucleic acid molecule exits the second channel 32. In the above preferred embodiment, the data acquisition time of the nucleic acid molecule analysis system is increased by the configuration and length of the second fluid channel 30 and the corresponding fourth electrode 70, so that the first electrode 40 as the detection electrode does not acquire data only when the label is located in the first channel 31 with a shorter length.
The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and are intended to be within the scope of the invention.

Claims (3)

1. A method for the analytical identification of nucleic acid molecules for identifying tag-conjugated nucleic acid molecules, comprising: (1) flowing the tag-coupled nucleic acid molecule through a first fluid channel having a width greater than the tag toward the nanopore; (2) the diameter of the nanopore is smaller than the diameter of the tag; measuring a change in current of an electrode proximate to the nanopore as the nucleic acid molecule flows into the nanopore; determining the sequence of the nucleic acid molecule from the change in current; (3) after the measurement is completed, the nucleic acid molecule coupled with the label is made to flow out of the nucleic acid molecule analysis and identification system through an outflow path without overlapping with an inflow path of the nucleic acid molecule above the nanopore.
2. The method for analyzing and identifying nucleic acid molecules according to claim 1, wherein: the time at which the currently tagged nucleic acid molecule exits the nucleic acid molecule analysis and identification system at step (3) partially overlaps with the time at which the next tagged nucleic acid molecule is flowed through the first fluid channel to the nanopore at step (1).
3. The method for analyzing and identifying nucleic acid molecules according to claim 1, wherein: the outflow path includes a second fluid passage having a width greater than the label diameter.
CN201911208274.9A 2019-11-30 2019-11-30 Nucleic acid molecule analysis and identification method Withdrawn CN110904205A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911208274.9A CN110904205A (en) 2019-11-30 2019-11-30 Nucleic acid molecule analysis and identification method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201911208274.9A CN110904205A (en) 2019-11-30 2019-11-30 Nucleic acid molecule analysis and identification method

Publications (1)

Publication Number Publication Date
CN110904205A true CN110904205A (en) 2020-03-24

Family

ID=69821735

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201911208274.9A Withdrawn CN110904205A (en) 2019-11-30 2019-11-30 Nucleic acid molecule analysis and identification method

Country Status (1)

Country Link
CN (1) CN110904205A (en)

Similar Documents

Publication Publication Date Title
US20200348293A1 (en) Target Detection with Nanopore
EP2205765B1 (en) Capture, recapture, and trapping of molecules with a nanopore
RU2681822C2 (en) Target sequence detection by nanopore sensing of synthetic probes
US20190226021A1 (en) Systems and methods for automated reusable parallel biological reactions
US20180335418A1 (en) Multiplexed biomarker quantitation by nanopore analysis of biomarker-polymer complexes
JP2018510329A5 (en)
US20060105461A1 (en) Nanopore analysis system
RU2006126664A (en) ANALYTES INPUT SYSTEM
Phillips et al. Continuous analysis of dye-loaded, single cells on a microfluidic chip
EP1702684A2 (en) Microfluidic devices and methods of using microfluidic devices
US20080213823A1 (en) Capillary-channeled polymer film flow cytometry
US20140234980A1 (en) Devices with a fluid transport nanochannel intersected by a fluid sensing nanochannel and related methods
CN114829626A (en) Methods and systems for microfluidic screening
Montes et al. Transverse migration and microfluidic concentration of DNA using Newtonian buffers
CN110904205A (en) Nucleic acid molecule analysis and identification method
CN110747117A (en) Nucleic acid molecule analysis system
US20230073771A1 (en) System and method for label-free single molecule detection
US20200200655A1 (en) Devices and methods for processing fluid samples
US20110294117A1 (en) Nucleic acid sequencing device and method of determining nucleotide sequence of target nucleic acid using the same
US11454624B2 (en) Nanopore technologies
Bandara et al. Advancements in the performance of nanopore sensing and its implications towards the identification of biomarkers
Wei Optical DNA Sequencing in a Nanopore Array
Yu et al. Fingerprinting full-length proteins through single-file translocations
JP2006242612A (en) Plate for discriminating biological sample
Jain et al. Sensing of protein and DNA complexes using solid-state nanopores

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
WW01 Invention patent application withdrawn after publication

Application publication date: 20200324

WW01 Invention patent application withdrawn after publication