Preparation method and application of nitrogen-sulfur-double-doped-graphene-oxide-labeled sandwich type immunosensor

Abstract

The invention, which belongs to the technical field of immunoassay and biosensing, provides a preparation method and application of a nitrogen-sulfur-double-doped-graphene-oxide-labeled sandwich typeimmunosensor. Thionine and gold platinum nuclear-shell dendritic crystal nanoparticle functionalized nitrogen-sulfur double-doped graphene oxide is used a catalytic material; and after incubation of the thionine and gold platinum nuclear-shell dendritic crystal nanoparticle functionalized nitrogen-sulfur double-doped graphene oxide with a detection antibody, a labeling substance is formed. Gold nano rod functionalized polydopamine is used as an electrode modification material. The prepared sandwich type electrochemical immunosensor is capable of realizing quantitative detection of cardiac troponin cTnI and cTnT by differential pulse voltammetry. The sensitivity and specificity are high and the detection limit is low. The preparation method and application of a nitrogen-sulfur-double-doped-graphene-oxide-labeled sandwich type immunosensor has the important scientific significance and great application value in early-stage detection of the cardiac troponin.

Description

technical field

[0001] The invention belongs to the technical field of immune analysis and biosensing, and relates to a preparation method and application of a nitrogen-sulfur double-doped graphene oxide-labeled sandwich-type immune sensor. Specifically, nitrogen-sulfur double-doped graphene oxide functionalized with thionine and gold-platinum core-shell dendritic nanoparticles was used as the catalytic material to label the detection antibody, and polydopamine functionalized with gold nanorods was used as the electrode modification material. Pulse voltammetry achieves sensitive detection of cardiac troponin. Background technique

[0002] Acute myocardial infarction (AMI), as the first killer that endangers human life and health, has the characteristics of acute onset and high mortality. Cardiac troponin is currently considered to be a better marker of myocardial damage, and it plays an important role in the early diagnosis and treatment of AMI. Therefore, a method with hi...

Examples

Embodiment 1

[0042] Embodiment 1 A method for preparing a nitrogen-sulfur double-doped graphene oxide-labeled sandwich-type immunosensor, comprising the following steps:

[0043] (1) A glassy carbon electrode with a diameter of 3.0mm is covered with Al 2 o 3 Grinding with polishing powder, cleaning with ultrapure water;

[0044] (2) Take 6.0 µL, 1.0 mg / mL gold nanorod functionalized polydopamine dispersion and apply it onto the electrode surface, dry it at room temperature, rinse the electrode surface with ultrapure water, and dry it;

[0045] (3) Add 6.0 µL, 8.0 µg / mL marker capture antibody Ab 1 Add dropwise to the surface of the electrode, rinse with ultrapure water, and dry in a refrigerator at 4 °C;

[0046] (4) Continue to add 3.0 µL, 0.8 mg / mL bovine serum albumin BSA solution dropwise to the electrode surface, rinse the electrode surface with ultrapure water, and dry it in a refrigerator at 4 °C;

[0047] (5) Add 6.0 µL, 0.00005 ~ 200 ng / mL of a series of marker antigen Ag solu...

Embodiment 2

[0049] Embodiment 2 A method for preparing a nitrogen-sulfur double-doped graphene oxide-labeled sandwich-type immunosensor, comprising the following steps:

[0050] (1) A glassy carbon electrode with a diameter of 4.0 mm is covered with Al 2 o 3 Grinding with polishing powder, cleaning with ultrapure water;

[0051] (2) Take 6.0 µL, 2.0 mg / mL gold nanorod functionalized polydopamine dispersion and apply it onto the electrode surface, dry it at room temperature, rinse the electrode surface with ultrapure water, and dry it;

[0052] (3) Add 6.0 µL, 10 µg / mL marker capture antibody Ab 1 Add dropwise to the surface of the electrode, rinse with ultrapure water, and dry in a refrigerator at 4 °C;

[0053] (4) Continue to add 3.0 µL, 1.0 mg / mL bovine serum albumin BSA solution dropwise to the electrode surface, rinse the electrode surface with ultrapure water, and dry it in a refrigerator at 4 °C;

[0054] (5) Add 6.0 µL, 0.00005 ~ 200 ng / mL of a series of marker antigen Ag solu...

Embodiment 3

[0056] Embodiment 3 A method for preparing a nitrogen-sulfur double-doped graphene oxide-labeled sandwich-type immunosensor, comprising the following steps:

[0057] (1) A glassy carbon electrode with a diameter of 5.0 mm is covered with Al 2 o 3 Grinding with polishing powder, cleaning with ultrapure water;

[0058] (2) Take 6.0 µL, 3.0 mg / mL gold nanorod functionalized polydopamine dispersion and apply it onto the electrode surface, dry it at room temperature, rinse the electrode surface with ultrapure water, and dry it;

[0059] (3) Add 6.0 µL, 12 µg / mL marker capture antibody Ab 1 Add dropwise to the surface of the electrode, rinse with ultrapure water, and dry in a refrigerator at 4 °C;

[0060] (4) Continue to add 3.0 µL, 1.2 mg / mL bovine serum albumin BSA solution dropwise to the electrode surface, rinse the electrode surface with ultrapure water, and dry it in a refrigerator at 4 °C;

[0061] (5) Add 6.0 µL, 0.00005 ~ 200 ng / mL of a series of marker antigen Ag solu...

technical field

[0001] The invention belongs to the technical field of immune analysis and biosensing, and relates to a preparation method and application of a nitrogen-sulfur double-doped graphene oxide-labeled sandwich-type immune sensor. Specifically, nitrogen-sulfur double-doped graphene oxide functionalized with thionine and gold-platinum core-shell dendritic nanoparticles was used as the catalytic material to label the detection antibody, and polydopamine functionalized with gold nanorods was used as the electrode modification material. Pulse voltammetry achieves sensitive detection of cardiac troponin. Background technique

[0002] Acute myocardial infarction (AMI), as the first killer that endangers human life and health, has the characteristics of acute onset and high mortality. Cardiac troponin is currently considered to be a better marker of myocardial damage, and it plays an important role in the early diagnosis and treatment of AMI. Therefore, a method with hi...

Examples

Embodiment 1

[0042] Embodiment 1 A method for preparing a nitrogen-sulfur double-doped graphene oxide-labeled sandwich-type immunosensor, comprising the following steps:

[0043] (1) A glassy carbon electrode with a diameter of 3.0mm is covered with Al 2 o 3 Grinding with polishing powder, cleaning with ultrapure water;

[0044] (2) Take 6.0 µL, 1.0 mg / mL gold nanorod functionalized polydopamine dispersion and apply it onto the electrode surface, dry it at room temperature, rinse the electrode surface with ultrapure water, and dry it;

[0045] (3) Add 6.0 µL, 8.0 µg / mL marker capture antibody Ab 1 Add dropwise to the surface of the electrode, rinse with ultrapure water, and dry in a refrigerator at 4 °C;

[0046] (4) Continue to add 3.0 µL, 0.8 mg / mL bovine serum albumin BSA solution dropwise to the electrode surface, rinse the electrode surface with ultrapure water, and dry it in a refrigerator at 4 °C;

[0047] (5) Add 6.0 µL, 0.00005 ~ 200 ng / mL of a series of marker antigen Ag solu...

Embodiment 2

[0049] Embodiment 2 A method for preparing a nitrogen-sulfur double-doped graphene oxide-labeled sandwich-type immunosensor, comprising the following steps:

[0050] (1) A glassy carbon electrode with a diameter of 4.0 mm is covered with Al 2 o 3 Grinding with polishing powder, cleaning with ultrapure water;

[0051] (2) Take 6.0 µL, 2.0 mg / mL gold nanorod functionalized polydopamine dispersion and apply it onto the electrode surface, dry it at room temperature, rinse the electrode surface with ultrapure water, and dry it;

[0052] (3) Add 6.0 µL, 10 µg / mL marker capture antibody Ab 1 Add dropwise to the surface of the electrode, rinse with ultrapure water, and dry in a refrigerator at 4 °C;

[0053] (4) Continue to add 3.0 µL, 1.0 mg / mL bovine serum albumin BSA solution dropwise to the electrode surface, rinse the electrode surface with ultrapure water, and dry it in a refrigerator at 4 °C;

[0054] (5) Add 6.0 µL, 0.00005 ~ 200 ng / mL of a series of marker antigen Ag solu...

Embodiment 3

[0056] Embodiment 3 A method for preparing a nitrogen-sulfur double-doped graphene oxide-labeled sandwich-type immunosensor, comprising the following steps:

[0057] (1) A glassy carbon electrode with a diameter of 5.0 mm is covered with Al 2 o 3 Grinding with polishing powder, cleaning with ultrapure water;

[0058] (2) Take 6.0 µL, 3.0 mg / mL gold nanorod functionalized polydopamine dispersion and apply it onto the electrode surface, dry it at room temperature, rinse the electrode surface with ultrapure water, and dry it;

[0059] (3) Add 6.0 µL, 12 µg / mL marker capture antibody Ab 1 Add dropwise to the surface of the electrode, rinse with ultrapure water, and dry in a refrigerator at 4 °C;

[0060] (4) Continue to add 3.0 µL, 1.2 mg / mL bovine serum albumin BSA solution dropwise to the electrode surface, rinse the electrode surface with ultrapure water, and dry it in a refrigerator at 4 °C;

[0061] (5) Add 6.0 µL, 0.00005 ~ 200 ng / mL of a series of marker antigen Ag solu...