CN104950031A - Nanopore detection system based on conductive polymer nanopore integrated structure and manufacturing method of nanopore detection system - Google Patents

Abstract

The invention relates to a nanopore detection system based on a conductive polymer nanopore integrated structure and a preparation method thereof. The system includes an electrolyte solution chamber, a conductive polymer nanopore integrated structure and a current detection system; the conductive polymer nanopore integrated structure It includes a nanoporous layer film with nanopores and a conductive polymer film with a micro-nano structure; the conductive polymer nanopore integrated structure is arranged inside the electrolyte solution chamber and is divided into an upper chamber and a lower chamber to form a channel; the current The detection system is arranged in the upper and lower chambers. The present invention integrates conductive polymers and nanopores through simple chemical modification of solid-state nanopores, and uses the formed porous micro-nano structure to complicate the movement path of long-chain polymers before passing through nanopores. The electrostatic force between the substance and the long-chain polymer molecule slows down or even controls the transmission speed of the long-chain polymer in the nanopore, which effectively improves the reliability of the nanopore detection of the long-chain polymer.

Description

Nanopore detection system based on conductive polymer nanopore integrated structure and its preparation method

technical field

The invention belongs to the technical field of nanopore detection, and relates to a nanopore detection system based on a conductive polymer nanopore integrated structure and a preparation method thereof, which can be used for detecting long-chain polymers (DNA, RNA or polypeptide).

Background technique

At present, using solid-state nanopores to detect long-chain polymers (DNA, RNA, or polypeptides) has the advantages of low cost, high read length, and easy integration, but the transmission speed of long-chain polymers in solid-state nanochannels greatly affects Its detection and identification effect, and long-chain polymers tend to stay near the nanopore, causing nanopore blockage. How to realize the controllable adjustment of the transmission speed of long-chain polymers in nanopores and reduce the blockage of long-chain polymers on nanopores is the key technical difficulty faced by nanopore sequencing technology.

Therefore, there is an urgent need for a detection system that allows long-chain polymers to pass through nanopores at a controlled rate, and integrating micro-nano network structures on nanoporous films is an effective means to construct such a system.

Contents of the invention

In view of this, the object of the present invention is to provide a nanopore detection system based on a conductive polymer nanopore integrated structure and a preparation method thereof, which can be used to detect long-chain polymers, and can slow down the long-chain polymers to be measured through the nanopores. In addition, it can effectively avoid the phenomenon of long-chain polymers clogging nanopores.

To achieve the above object, the present invention provides the following technical solutions:

A nanopore detection system based on a conductive polymer nanopore integrated structure, including an electrolyte solution chamber, a conductive polymer nanopore integrated structure, and an amperometric detection system for detecting long-chain polymers;

The nanoporous integrated structure of the conductive polymer comprises a nanoporous film and a conductive polymer film close to the nanoporous film, and the nanoporous film is provided with nanopores; the conductive polymer film has micro-nano Pore Structure;

The conductive polymer nanopore integrated structure is arranged inside the electrolyte solution chamber and is divided into an upper chamber and a lower chamber, and the nanopore and the micro-nano pore structure in the conductive polymer film form a connection between the upper chamber and the lower chamber. the channel of the chamber;

The current detection system includes a power supply, electrode I, electrode II and ammeter; the electrode I and electrode II are placed in the upper chamber and the lower chamber respectively; the power supply, electrode I, electrode II and ammeter are connected in series to detect The circuit of the object to be detected.

Further, there may be one or more nanopores provided on the nanoporous film.

Further, the conductive polymer film has a micro-nano pore structure, and the materials are conductive polymers such as polypyrrole, polyaniline, polythiophene and poly-3,4-ethylenedioxythiophene and related modified or doped composite materials .

Further, the conductive polymer film can be on one side of the nanoporous film, or on the upper and lower sides of the nanoporous film.

Further, the material of the nanoporous film is one of silicon nitride, graphene, molybdenum disulfide, silicon dioxide or aluminum oxide film.

Further, it also includes a DNA sequencing device and a protein sequencing device with a conductive polymer nanopore integrated structure.

The present invention also provides a method for preparing a nanopore detection system based on a conductive polymer nanopore integrated structure, comprising the following steps:

Step 1: Generate a nanoporous film on both sides of the silicon wafer;

Step 2: forming nanopores on the nanoporous film;

Step 3: Carrying out surface modification to the nanoporous film;

Step 4: forming a conductive polymer film on the modified nanoporous film;

Step 5: Place the conductive polymer nanopore integrated structure inside the electrolyte solution chamber and divide it into an upper chamber and a lower chamber, and make the nanopores and the micro-nano pores on the conductive polymer connect the upper chamber and the lower chamber the channel of the chamber;

Step 6: Set one end of the current detection system in the upper chamber, and the other end in the lower chamber to form a circuit for detecting the object to be detected.

Further, the formation method in step 4 includes chemical oxidation polymerization and electrochemical polymerization.

Further, the current detection system in the step 6 includes a power supply, electrode I, electrode II and ammeter; the electrode I and electrode II are placed in the upper chamber and the lower chamber respectively; the power supply, electrode I, electrode II and current The meters are connected in series to form a circuit for detecting the substance to be detected.

The beneficial effect of the present invention is that: the present invention utilizes the porous micro-nano structure formed by the conductive polymer that can be synthesized by a simple method to complicate the movement path of the long-chain polymer before passing through the nanopore, combining the conductive polymer with the long-chain polymer The electrostatic force between the molecules can slow down or even control the transmission speed of the long-chain polymer in the nanopore, and at the same time realize the linearization of the long-chain polymer before passing through the nanopore, break the entanglement state of the long-chain polymer, and avoid the long-chain The polymer blocks the nanopore, which effectively improves the reliability of the nanopore for detecting long-chain polymers.

Description of drawings

In order to make the purpose, technical scheme and beneficial effect of the present invention clearer, the present invention provides the following drawings for illustration:

Fig. 1 is a schematic flow chart of making a conductive polymer-nanopore integrated structure according to an embodiment of the present invention;

Fig. 2 is a conductive polymer-nanopore integrated structure diagram prepared by the embodiment of the present invention;

3 is a schematic structural diagram of a nanopore detection system based on a conductive polymer-nanopore integrated structure prepared in an embodiment of the present invention;

Among them: 1-silicon nitride film, 2-conductive polymer film, 3-nanopore, 4-upper chamber, 5-lower chamber, 6-power supply, 7-electrode Ⅰ, 8-electrode Ⅱ, 9-current Meter, 10-long chain polymer.

Detailed ways

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

Example 1:

A nanopore detection system based on a conductive polymer nanopore integrated structure provided in this embodiment includes an electrolyte solution chamber, a conductive polymer nanopore integrated structure, and a current detection system;

The conductive polymer nanopore integrated structure includes a nanoporous film and a conductive polymer film superimposed on it. The nanoporous film in this embodiment is a silicon nitride film 1; the conductive polymer film is a polypyrrole film 2; The nanoporous film is provided with nanopores 3; the polypyrrole film has a micro-nano pore structure;

The conductive polymer nanopore integrated structure is arranged inside the electrolyte solution chamber and is divided into an upper chamber 4 and a lower chamber 5, and the nanopore 3 and the micro-nano pore structure in the conductive polymer film form a connected upper chamber chamber 4 and lower chamber 5 channels;

One end of the current detection system is arranged in the upper chamber, and the other end is arranged in the lower chamber to form a circuit for detecting the object to be detected.

The micro-nano pores formed on the conductive polymer film are connected through the nanopores provided on the nanoporous layer film.

The current detection system includes a power supply 6, an electrode I7, an electrode II8 and an ammeter 9;

The electrodes I7 and II8 are respectively placed in the upper chamber 4 and the lower chamber 5;

The power supply 6, electrode I7, electrode II8 and ammeter 9 are connected in series to form a circuit for detecting the object to be detected.

The material for making the conductive polymer film in this embodiment can also be selected from conductive polymers such as polypyrrole, polyaniline, polythiophene and poly-3,4-ethylenedioxythiophene and related modified or doped composite materials.

The material for making the nanoporous film in this embodiment can also be selected from one of graphene, molybdenum disulfide, silicon dioxide or aluminum oxide film.

This embodiment also provides a preparation method of a nanopore detection system based on a conductive polymer nanopore integrated structure, including the following steps:

1) Generate a nanoporous film on both sides of the silicon wafer;

2) forming nanopores on the nanoporous film;

3) surface modification of the nanoporous film;

4) forming a conductive polymer film on the modified nanoporous film;

5) The conductive polymer nanopore integrated structure is placed inside the electrolyte solution chamber and divided into an upper chamber and a lower chamber, and the nanopores and the micro-nano pores in the conductive polymer film form a connection between the upper chamber and the lower chamber aisle;

6) One end of the current detection system is arranged in the upper chamber, and the other end is arranged in the lower chamber to form a circuit for detecting the object to be detected.

The current detection system includes a power supply 6, an electrode I7, an electrode II8 and an ammeter 9;

The electrodes I7 and II8 are respectively placed in the upper chamber 4 and the lower chamber 5;

The power supply 6, electrode I7, electrode II8 and ammeter 9 are connected in series to form a circuit for detecting the object to be detected.

The material of the conductive polymer film can also be selected from conductive polymers such as polypyrrole, polyaniline, polythiophene and poly-3,4-ethylenedioxythiophene and related modified or doped composite materials.

The material of the nanoporous film is one of silicon nitride, graphene, molybdenum disulfide, silicon dioxide or aluminum oxide film.

Example 2

As shown in Figure 1, the preparation method of the conductive polymer-nanopore integrated structure provided in this embodiment is specifically implemented according to the following steps:

The nanoporous film provided in this embodiment is a self-supporting silicon nitride film, and the conductive polymer film is a polypyrrole film.

1) On both sides of the silicon wafer, use low-pressure chemical vapor deposition or plasma-enhanced chemical vapor deposition to grow silicon nitride films; then form a self-supporting silicon nitride film through a semiconductor process;

2) Using focused ion beam or transmission electron microscopy to form nanopores on silicon nitride films;

3) surface modification of the nanoporous film;

4) forming a polypyrrole film on the modified nanoporous film;

As shown in FIG. 2 , it is an effect diagram of the finally formed polypyrrole-nanopore integrated structure.

As shown in Figure 3, the conductive polymer-nanopore integrated structure prepared in the previous steps is assembled with the electrolyte solution chamber and the current detection system to obtain the nanopore detection system based on the conductive polymer-nanopore integrated structure .

In this embodiment, the self-supporting silicon nitride film 1 has a thickness of 0.5-50 nanometers, and can also be other different thicknesses;

In this embodiment, the diameter of the nanopore 3 is 0.5-10 nanometers, and may also be of other different sizes.

In this embodiment, the polypyrrole film 2 may be doped or undoped.

In this embodiment, the size of the micro-nano pore structure on the polypyrrole film 2 can be micron and submicron, or other different sizes, but it is much larger than the nanopore 3 .

In this embodiment, the polypyrrole film 2 may be on one side of the nanopore, or on the upper and lower sides of the nanopore.

In this embodiment, the long-chain polymer may be DNA, RNA or polypeptide.

In summary, the present invention provides a nanopore detection system based on the integrated structure of conductive polymer nanopores, which uses the porous micro-nano structure formed by the conductive polymer that can be synthesized by a simple method to make the long-chain polymer pass through the nanopore The movement path in front of the hole is complicated, combined with the electrostatic force between the conductive polymer and the long-chain polymer molecule, slows down or even controls the transmission speed of the long-chain polymer in the nanopore, and realizes the long-chain polymer to pass through the nanopore The previous linearization breaks the entangled state of long-chain polymers, prevents long-chain polymers from blocking nanopores, and effectively improves the reliability of nanopore detection of long-chain polymers. Therefore, the present invention effectively overcomes various shortcomings in the prior art. And it has high industrial utilization value.

Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that it can be described in terms of form and Various changes may be made in the details without departing from the scope of the invention defined by the claims.

Claims (9)

1. based on a nano-pore detection system for conductive polymer nanometer hole integrated morphology, it is characterized in that: comprise electrolyte solution chamber, conductive polymer nanometer hole integrated morphology and the current detecting system for detecting long chain polymer;

Described conductive polymer nanometer hole integrated morphology comprises nano-pore layer film and is close to the conducting polymer thin film on nano-pore layer film, and described nano-pore layer film is provided with nano-pore; Described conducting polymer thin film has micro-nano hole gap structure;

Described conductive polymer nanometer hole integrated morphology is arranged at electrolyte solution chamber interior and is divided into upper chamber and lower chambers, and described nano-pore forms with the micro-nano hole gap structure in conducting polymer thin film the passage being communicated with upper chamber and lower chambers;

Described current detecting system comprises power supply, electrode I, electrode II and galvanometer; Described electrode I and electrode II are placed in upper chamber and bottom chamber respectively; The series connection of power supply, electrode I, electrode II and galvanometer forms the circuit for detecting thing to be detected.

2. a kind of nano-pore detection system based on conductive polymer nanometer hole integrated morphology according to claim 1, is characterized in that: the nano-pore that described nano-pore layer film is arranged can be one or more.

3. a kind of nano-pore detection system based on conductive polymer nanometer hole integrated morphology according to claim 1, it is characterized in that: described conducting polymer thin film has micro-nano hole gap structure, material is the compound substance of the conducting polymers such as polypyrrole, polyaniline, polythiophene and poly-3,4-rthylene dioxythiophene and relevant modification or doping.

4. a kind of nano-pore detection system based on conductive polymer nanometer hole integrated morphology according to claim 1, is characterized in that: described conducting polymer thin film can in the side of nano-pore layer film, also can in the both sides up and down of nano-pore layer film.

5. a kind of nano-pore detection system based on conductive polymer nanometer hole integrated morphology according to claim 1, is characterized in that: the material of described nano-pore layer film is the one in silicon nitride, Graphene, molybdenum disulfide, silicon dioxide or alundum (Al2O3) film.

6. a kind of nano-pore detection system based on conductive polymer nanometer hole integrated morphology according to claim 1, is characterized in that: the DNA sequencing device and the protein sequencing device that also comprise conductive polymer nanometer hole integrated morphology.

7., based on a nano-pore detection system preparation method for conductive polymer nanometer hole integrated morphology, it is characterized in that: comprise the following steps:

Step one: generate nano-pore layer film on silicon chip two sides;

Step 2: form nano-pore on nano-pore layer film;

Step 3: surface modification is carried out to nano-porous thin film;

Step 4: form conducting polymer thin film on the nano-porous thin film of modification;

Step 5: conductive polymer nanometer hole integrated morphology is arranged at electrolyte solution chamber interior and is divided into upper chamber and lower chambers, and make nano-pore form with the micro-nano hole on conducting polymer the passage being communicated with upper chamber and lower chambers;

Step 6: be arranged in upper chamber by current detecting system one end, the other end is arranged at bottom chamber and forms the circuit for detecting thing to be detected.

8. a kind of nano-pore detection system preparation method based on conductive polymer nanometer hole integrated morphology according to claim 7, is characterized in that: the formation method in described step 4 comprises chemical oxidative polymerization and electrochemical polymerization method.

9. a kind of nano-pore detection system preparation method based on conductive polymer nanometer hole integrated morphology according to claim 7, is characterized in that: the current detecting system in described step 6 comprises power supply, electrode I, electrode II and galvanometer; Described electrode I and electrode II are placed in upper chamber and bottom chamber respectively; The series connection of power supply, electrode I, electrode II and galvanometer forms the circuit for detecting thing to be detected.