A colloidal gold preparation method for Helicobacter pylori antigen detection test strip and a test strip preparation method

Abstract

The present invention relates to a method for preparing colloidal gold for a gastric Helicobacter pylori antigen detection test strip and a method for preparing the test strip, belonging to the field of bio-immunology technology. A method for preparing colloidal gold for a gastric Helicobacter pylori antigen detection test strip includes the following steps: (1) Add 100 mL of 0.02% HAuCl4 solution into a three-necked flask, place the three-necked flask on a magnetic stirring electrothermal mantle, heat it to boiling under reflux condensation, and quickly add 2 mL of 2% sodium citrate solution while stirring at a speed of 300 rpm for reaction. The solution in the three-necked flask changes from yellow through colorless to black and then gradually turns pink. Continue to heat under reflux condensation for 10 - 15 min to generate a seed solution, and cool it for later use; this preparation method can significantly improve problems such as uneven particle morphology and particle size and instability of colloidal gold in the existing colloidal gold preparation technology, and enhance the performance such as sensitivity and stability of the gastric Helicobacter pylori antigen detection test strip.

Description

Technical Field

[0001] The invention relates to the field of biological immunity technology, in particular to a method for preparing colloidal gold for a test strip for detecting gastric Helicobacter pylori antigen and a method for preparing the test strip. Background Art

[0002] Helicobacter pylori is a Gram-negative bacterium that is often located on the surface of the gastric mucosal epithelium, in the gastric antrum and glandular cavity, and under the mucus layer. The pathogenic mechanism of Helicobacter pylori is complex and can further induce a variety of diseases, such as chronic gastritis, gastric ulcer, etc.

[0003] The detection method of Helicobacter pylori antigen test paper has the advantages of simple operation and rapid detection, and can achieve instant detection with a high accuracy rate. At present, colloidal gold, i.e., nanogold solution, is generally used in the preparation process of Helicobacter pylori antigen test paper strips. The various properties of nanogold depend on the size and morphology of nanogold particles. Nanogold particles are widely studied in many fields such as optics, nano-microelectronics, and biomedicine. At present, various preparation methods of nanogold particles have been improved according to demand in different fields, such as adding surfactants such as PVP and PEG as protective agents to improve the stability of colloidal gold, adding CTAB, EOA, etc. as structure-directing agents to prepare nanogold rods and nanogold flowers, and preparing nanogold particles with different properties through microwave synthesis, seed growth synthesis, laser crushing synthesis, etc. These methods can stably prepare nanogold particles with a particle size of 10-40nm. When further preparing nanogold particles with larger particle sizes, it is very easy to have problems of uneven particle size and different morphologies, resulting in instability of colloidal gold solution. When applied to immune labeling, it is easy to have problems such as low sensitivity and poor specificity. Summary of the invention

[0004] The purpose of the present invention is to provide a colloidal gold preparation method for Helicobacter pylori antigen detection test strips and a test strip preparation method, which can significantly improve the problems of particle morphology and particle size unevenness, colloidal gold instability and the like in the existing colloidal gold preparation technology, and improve the sensitivity and stability of the Helicobacter pylori antigen detection test strips.

[0005] To achieve the above object, the technical solution adopted by the present invention is as follows: A method for preparing colloidal gold for Helicobacter pylori antigen detection test strips comprises the following steps:

[0006] (1) Add 100 mL of 0.02% HAuCl4 solution to a three-necked flask, place the three-necked flask on a magnetic stirring electric heating mantle, heat to boiling by condensation reflux, stir at 300 rpm, quickly add 2 mL of 2% sodium citrate solution to react, the solution in the three-necked flask changes from yellow to colorless to black, and then gradually turns pink, continue condensation reflux heating for 10-15 minutes to generate seed solution, cool and set aside;

[0007] (2) Add 256-262 mL of water to another three-necked flask, place the three-necked flask on a magnetic stirring heating mantle, heat under condensation reflux until boiling for 3 min, then stop heating until boiling stops;

[0008] (3) quickly add 6-10 mL of the seed solution prepared in step (1) and 1 mL of 2% sodium citrate solution, then turn on the magnetic stirring switch and stir evenly;

[0009] (4) stirring at 300 rpm and adding dropwise 0.1% HAuCl4 solution and 2% sodium citrate solution for 1 min, with the flow rate of 0.1% HAuCl4 solution being 30 mL / min and the flow rate of 2% sodium citrate solution being 1-3 mL / min;

[0010] After the addition of HAuCl4 solution and sodium citrate solution was completed, the speed of the electric heating mantle was adjusted to 100 rpm, and the final colloidal gold solution was generated by heating, condensing and reflux for 10 minutes.

[0011] As an optimization scheme, in step (2), 259.4 mL of water was added.

[0012] As an optimization scheme, in step (3), 6 mL of the seed solution prepared in step (1) is added.

[0013] As an optimization scheme, in step (4), the flow rate of the 2% by mass sodium citrate solution is 2 mL / min.

[0014] A method for preparing a Helicobacter pylori antigen detection test strip comprises the following steps:

[0015] (1) Preparation of binding pad: Take the colloidal gold solution prepared above, stir with 0.2M K2CO3 solution to adjust the pH value of the colloidal gold solution to 7.8, add 5 μg / mL of Helicobacter pylori antigen to the colloidal gold solution and stir for 5 min, then add BSA with a final concentration of 0.5% and react for 20 min to complete labeling, centrifuge the labeled colloidal gold at 10000 rpm for 30 min at 4 °C, remove the supernatant and re-dissolve it with re-solution to 1 / 10 of the original concentration, and centrifuge the re-dissolved liquid at 0.5 mL / cm2 The coating is applied to the glass fiber and dried to form a bonding pad.

[0016] As an optimization solution, the formula of the reconstitution solution is: 0.2% (W / V) Tris, 0.75% (W / V) casein, 0.8% (W / V) BSA, 0.8% (W / V) Tween-20, 0.5% (W / V) sucrose, pH 7.8.

[0017] As an optimization solution, the following steps are also included:

[0018] (2) Sample pad preparation: Take 10 g Triton X-100, 18 g polyvinyl pyrrolidone, 5 g surfactant S9, 18 g bovine serum albumin, and 8 mL Tween-20, dilute to 1 L with 10 mM phosphate buffer, adjust the final pH value to 8.0, and then immerse the glass fiber in it. After taking it out, dry it to make a sample pad.

[0019] As an optimization solution, the following steps are also included:

[0020] (3) Coating of quality control line and test line: Helicobacter pylori monoclonal antibody and goat anti-mouse IgG were coated on nitrocellulose membrane at 1.0 μg / mL and 1.25 μg / mL respectively.

[0021] As an optimization solution, the following steps are also included:

[0022] (4) Paste the sample pad, conjugate pad, nitrocellulose membrane and absorbent paper on the bottom plate in order, cut them into 2 mm wide pieces and assemble them in the card shell to obtain the test strip.

[0023] The present invention adopts the above technical solution and has the following advantages:

[0024] Sodium citrate modification of colloidal gold will not affect the binding of colloidal gold to biomacromolecules. Using the same reducing agent for seed preparation and subsequent growth can reduce the difference in competitive modification of the colloidal gold surface and improve the stability of colloidal gold.

[0025] The slow alternating addition of gold chloride and sodium citrate can control the concentration of gold atoms in the reaction system, avoiding explosive nucleation to form heterogeneous nano-gold nuclei, and instead growing uniformly on the basis of the original crystal nuclei of uniform shape and size. Stopping heating and stirring the reaction during the growth stage can reduce the impact of uneven heating while ensuring the reaction temperature.

[0026] The colloidal gold prepared by the invention has good stability, expands the adjustment range of biological immune markers, and the prepared test strip has the characteristics of high sensitivity, good specificity, etc.

[0027] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The ultraviolet spectrum scanning results of the colloidal gold prepared in Comparative Example 1 of the present invention and the colloidal gold prepared in Example 1 are shown. DETAILED DESCRIPTION

[0029] The embodiments of the present invention are described in detail below with reference to the examples. In the examples, the specific conditions are not specified, and the experiments are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used without specifying the manufacturer are all conventional products that can be purchased on the market.

[0030] The described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0031] All percentages in the following embodiments and comparative examples are by mass. Example 1

[0032] A method for preparing colloidal gold for Helicobacter pylori antigen detection test strips comprises the following steps:

[0033] (1) Add 100 mL of 0.02% HAuCl4 solution to a 250 mL three-necked flask, place the three-necked flask on a magnetic stirring electric heating mantle, heat to boiling by condensation reflux, stir at 300 rpm and quickly add 2 mL of 2% sodium citrate solution to react. The solution in the three-necked flask changes from yellow to colorless to black and then gradually turns pink. Continue condensation reflux heating for 10 min to generate seed solution, cool and set aside;

[0034] (2) Add 256 mL of water to a 500 mL three-necked flask, place the flask on a magnetic stirring heating mantle, heat under condensation reflux until boiling for 3 min, then stop heating until boiling stops;

[0035] (3) quickly add 6 mL of the seed solution prepared in step (1) and 1 mL of 2% sodium citrate solution, then turn on the magnetic stirring switch and stir evenly;

[0036] (4) Stirring at 300 rpm and turning on the titration pump to drip 0.1% HAuCl4 solution and 2% sodium citrate solution for 1 min. The flow rate of 0.1% HAuCl4 solution is 30 mL / min, and the flow rate of 2% sodium citrate solution is 1 mL / min.

[0037] After the addition of HAuCl4 solution and sodium citrate solution was completed, the speed of the electric heating mantle was adjusted to 100 rpm, and the final colloidal gold solution was generated by heating, condensing and reflux for 10 minutes.

[0038] A method for preparing a Helicobacter pylori antigen detection test strip comprises the following steps:

[0039] (1) Preparation of binding pad: Take the colloidal gold solution prepared above, stir with 0.2M K2CO3 solution to adjust the pH value of the colloidal gold solution to 7.8, add 5 μg / mL of Helicobacter pylori antigen to the colloidal gold solution and stir for 5 min, then add BSA with a final concentration of 0.5% and react for 20 min to complete labeling, centrifuge the labeled colloidal gold at 10000 rpm for 30 min at 4 °C, remove the supernatant and re-dissolve it with re-solution to 1 / 10 of the original concentration, and centrifuge the re-dissolved liquid at 0.5 mL / cm 2 The coating is then dried on the glass fiber to form a bonding pad;

[0040] The formula of the reconstitution solution is: 0.2% (W / V) Tris, 0.75% (W / V) casein, 0.8% (W / V) BSA, 0.8% (W / V) Tween-20, 0.5% (W / V) sucrose, pH 7.8;

[0041] (2) Sample pad preparation: Take 10 g Triton X-100, 18 g polyvinyl pyrrolidone, 5 g surfactant S9, 18 g bovine serum albumin, and 8 mL Tween-20, dilute to 1 L with 10 mM phosphate buffer, adjust the final pH value to 8.0, and then immerse the glass fiber in it. After taking it out, dry it to make a sample pad.

[0042] (3) Coating of quality control line and test line: Helicobacter pylori monoclonal antibody and goat anti-mouse IgG were coated on nitrocellulose membrane at 1.0 μg / mL and 1.25 μg / mL respectively.

[0043] (4) Paste the sample pad, conjugate pad, nitrocellulose membrane and absorbent paper on the bottom plate in order, cut them into 2 mm wide pieces and assemble them in the card shell to obtain the test strip. Example 2

[0044] A method for preparing colloidal gold for Helicobacter pylori antigen detection test strips comprises the following steps:

[0045] (1) Add 100 mL of 0.02% HAuCl4 solution to a 250 mL three-necked flask, place the three-necked flask on a magnetic stirring electric heating mantle, heat to boiling by condensation reflux, stir at 300 rpm, quickly add 2 mL of 2% sodium citrate solution to react, the solution in the three-necked flask changes from yellow to colorless to black, and then gradually turns pink, continue condensation reflux heating for 12 min to generate seed solution, cool and set aside;

[0046] (2) Add 259.4 mL of water to a 500 mL three-necked flask, place the flask on a magnetic stirring heating mantle, heat under condensation reflux until boiling for 3 min, then stop heating until boiling stops;

[0047] (3) quickly add 6 mL of the seed solution prepared in step (1) and 1 mL of 2% sodium citrate solution, then turn on the magnetic stirring switch and stir evenly;

[0048] (4) Stirring at 300 rpm and turning on the titration pump to drip 0.1% HAuCl4 solution and 2% sodium citrate solution for 1 min. The flow rate of 0.1% HAuCl4 solution is 30 mL / min, and the flow rate of 2% sodium citrate solution is 2 mL / min.

[0049] After the addition of HAuCl4 solution and sodium citrate solution was completed, the speed of the electric heating mantle was adjusted to 100 rpm, and the final colloidal gold solution was generated by heating, condensing and reflux for 10 minutes.

[0050] A method for preparing a Helicobacter pylori antigen detection test strip comprises the following steps:

[0051] (1) Preparation of binding pad: Take the colloidal gold solution prepared above, stir with 0.2M K2CO3 solution to adjust the pH value of the colloidal gold solution to 7.8, add 5 μg / mL of Helicobacter pylori antigen to the colloidal gold solution and stir for 5 min, then add BSA with a final concentration of 0.5% and react for 20 min to complete labeling, centrifuge the labeled colloidal gold at 10000 rpm for 30 min at 4 °C, remove the supernatant and re-dissolve it with re-solution to 1 / 10 of the original concentration, and centrifuge the re-dissolved liquid at 0.5 mL / cm 2 The coating is then dried on the glass fiber to form a bonding pad;

[0052] The formula of the reconstitution solution is: 0.2% (W / V) Tris, 0.75% (W / V) casein, 0.8% (W / V) BSA, 0.8% (W / V) Tween-20, 0.5% (W / V) sucrose, pH 7.8;

[0053] (2) Sample pad preparation: Take 10 g Triton X-100, 18 g polyvinyl pyrrolidone, 5 g surfactant S9, 18 g bovine serum albumin, and 8 mL Tween-20, dilute to 1 L with 10 mM phosphate buffer, adjust the final pH value to 8.0, and then immerse the glass fiber in it. After taking it out, dry it to make a sample pad.

[0054] (3) Coating of quality control line and test line: Helicobacter pylori monoclonal antibody and goat anti-mouse IgG were coated on nitrocellulose membrane at 1.0 μg / mL and 1.25 μg / mL respectively.

[0055] (4) Paste the sample pad, conjugate pad, nitrocellulose membrane and absorbent paper on the bottom plate in order, cut them into 2 mm wide pieces and assemble them in the card shell to obtain the test strip. Example 3

[0056] A method for preparing colloidal gold for Helicobacter pylori antigen detection test strips comprises the following steps:

[0057] (1) Add 100 mL of 0.02% HAuCl4 solution to a 250 mL three-necked flask, place the three-necked flask on a magnetic stirring electric heating mantle, heat to boiling by condensation reflux, stir at 300 rpm and quickly add 2 mL of 2% sodium citrate solution to react. The solution in the three-necked flask changes from yellow to colorless to black and then gradually turns pink. Continue condensation reflux heating for 15 min to generate seed solution, cool and set aside;

[0058] (2) Add 262 mL of water to a 500 mL three-necked flask, place the flask on a magnetic stirring heating mantle, heat under condensation reflux until boiling for 3 min, then stop heating until boiling stops;

[0059] (3) quickly add 10 mL of the seed solution prepared in step (1) and 1 mL of 2% sodium citrate solution, then turn on the magnetic stirring switch and stir evenly;

[0060] (4) Stirring at 300 rpm and turning on the titration pump to drip 0.1% HAuCl4 solution and 2% sodium citrate solution for 1 min. The flow rate of 0.1% HAuCl4 solution is 30 mL / min, and the flow rate of 2% sodium citrate solution is 3 mL / min.

[0061] After the addition of HAuCl4 solution and sodium citrate solution was completed, the speed of the electric heating mantle was adjusted to 100 rpm, and the final colloidal gold solution was generated by heating, condensing and reflux for 10 minutes.

[0062] A method for preparing a Helicobacter pylori antigen detection test strip comprises the following steps:

[0063] (1) Preparation of binding pad: Take the colloidal gold solution prepared above, stir with 0.2M K2CO3 solution to adjust the pH value of the colloidal gold solution to 7.8, add 5 μg / mL of Helicobacter pylori antigen to the colloidal gold solution and stir for 5 min, then add BSA with a final concentration of 0.5% and react for 20 min to complete labeling, centrifuge the labeled colloidal gold at 10000 rpm for 30 min at 4 °C, remove the supernatant and re-dissolve it with re-solution to 1 / 10 of the original concentration, and centrifuge the re-dissolved liquid at 0.5 mL / cm 2 The coating is then dried on the glass fiber to form a bonding pad;

[0064] The formula of the reconstitution solution is: 0.2% (W / V) Tris, 0.75% (W / V) casein, 0.8% (W / V) BSA, 0.8% (W / V) Tween-20, 0.5% (W / V) sucrose, pH 7.8;

[0065] (2) Sample pad preparation: Take 10 g Triton X-100, 18 g polyvinyl pyrrolidone, 5 g surfactant S9, 18 g bovine serum albumin, and 8 mL Tween-20, dilute to 1 L with 10 mM phosphate buffer, adjust the final pH value to 8.0, and then immerse the glass fiber in it. After taking it out, dry it to make a sample pad.

[0066] (3) Coating of quality control line and test line: Helicobacter pylori monoclonal antibody and goat anti-mouse IgG were coated on nitrocellulose membrane at 1.0 μg / mL and 1.25 μg / mL respectively.

[0067] (4) Paste the sample pad, conjugate pad, nitrocellulose membrane and absorbent paper on the bottom plate in order, cut them into 2 mm wide pieces and assemble them in the card shell to obtain the test strip.

[0068] In the seed crystal preparation process of the present invention, sodium citrate is used as a reducing agent, and sodium citrate is modified on the surface of the seed crystal to play a role as a stabilizer. During the growth process, gold chloride alternately added will be reduced by sodium citrate to form new gold atomic clusters, which are adsorbed on the surface of the added seed crystal and slowly accumulated, thereby achieving uniform growth of colloidal gold.

[0069] Comparative Example 1:

[0070] The colloidal gold particle size described in this comparative example is consistent with that in Example 1, and the colloidal gold preparation method described in this comparative example is a sodium citrate one-step reduction method.

[0071] One-step reduction method of sodium citrate: add 100 mL of 0.01% by mass HAuCl4 solution into a 250 mL three-necked flask, place the three-necked flask on a magnetic stirring electric heating mantle, heat to boiling with condensation reflux, stir at 300 rpm, quickly add 0.75 mL of 2% by mass sodium citrate solution to react, and heat under condensation reflux for 15 minutes.

[0072] The ultraviolet spectrum scanning results of the colloidal gold prepared in Comparative Example 1 and the colloidal gold prepared in Example 1 are as follows: Figure 1 As shown, the absorption peak wavelengths of both are around 524 nm, and the peak width of the colloidal gold prepared in Example 1 is smaller than that of the colloidal gold prepared in Comparative Example 1, that is, the dominant particle size of the nano-gold in the colloidal gold solution is consistent, the particle size of the colloidal gold prepared in Example 1 is more uniform, and the performance of the colloidal gold is more stable.

[0073] Comparative Example 2:

[0074] The difference between this comparative example and Example 1 is that the colloidal gold in this comparative example is prepared by sodium citrate one-step reduction method, and the other operations are the same, sodium citrate one-step reduction method:

[0075] Add 100 mL of 0.01% by mass HAuCl4 solution into a 250 mL three-necked flask, place the three-necked flask on a magnetic stirring electric heating mantle, heat to boiling with condensation reflux, stir at 300 rpm, quickly add 0.75 mL of 2% by mass sodium citrate solution to react, and heat under condensation reflux for 15 min.

[0076] Comparison of sensitivity and specificity of Helicobacter pylori antigen detection test strips:

[0077] The Helicobacter pylori antigen detection test strips prepared in Example 1 and Comparative Example 2 were used to test negative samples and positive samples, respectively. The results are shown in Tables 1 and 2:

[0078] Table 1

[0079]

[0080] Table 2

[0081]

[0082] The experimental results show that the true positive rate and true negative rate of positive samples in Example 1 are higher than those in Comparative Example 2; at the same time, the false positive rate and false negative rate of the test strip in Example 1 are also lower than those in Comparative Example 2, indicating that the sensitivity and specificity of the test strip prepared by the present invention are significantly better than those prepared by the conventional colloidal gold method.

[0083] After diluting the same positive sample, the detection capabilities of the Helicobacter pylori antigen detection test strips prepared in Example 1 and Comparative Example 2 were tested and compared, and the statistics were obtained in Table 3:

[0084] Table 3

[0085]

[0086] “-” indicates negative, “+” indicates positive, and the more “+” there are, the stronger the positive color development will be.

[0087] The experimental results show that Example 1 has a better color development effect on low-concentration positive samples than Comparative Example 2. When the positive sample is diluted 100 times, the test strip prepared by the conventional colloidal gold method cannot successfully detect it, but Example 1 can still detect the positive sample after 200 times dilution.

[0088] In summary, the sensitivity and specificity of the test strip prepared by the present invention are significantly superior to those of the test strip prepared by the conventional colloidal gold method.

[0089] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The examples of the implementation methods and the parts not described in detail are common knowledge of ordinary technicians in the field. For those skilled in the art, they can still modify the technical solutions recorded in the above embodiments, or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing colloidal gold for Helicobacter pylori antigen detection test strips, characterized in that: The steps include: (1) Add 100 mL of 0.02% HAuCl4 solution to a three-necked flask, place the three-necked flask on a magnetic stirring electric heating mantle, heat to boiling by condensation reflux, stir at 300 rpm, quickly add 2 mL of 2% sodium citrate solution to react, the solution in the three-necked flask changes from yellow to colorless to black, and then gradually turns pink, continue condensation reflux heating for 10-15 minutes to generate seed solution, cool and set aside; (2) Add 256-262 mL of water to another three-necked flask, place the three-necked flask on a magnetic stirring heating mantle, heat under condensation reflux until boiling for 3 min, then stop heating until boiling stops; (3) quickly add 6-10 mL of the seed solution prepared in step (1) and 1 mL of 2% sodium citrate solution, then turn on the magnetic stirring switch and stir evenly; (4) stirring at 300 rpm and adding dropwise 0.1% HAuCl4 solution and 2% sodium citrate solution for 1 min, with the flow rate of 0.1% HAuCl4 solution being 30 mL / min and the flow rate of 2% sodium citrate solution being 1-3 mL / min; After the addition of HAuCl4 solution and sodium citrate solution was completed, the speed of the electric heating mantle was adjusted to 100 rpm, and the final colloidal gold solution was generated by heating, condensing and reflux for 10 minutes.

2. The method for preparing colloidal gold for Helicobacter pylori antigen detection test strip according to claim 1, characterized in that: In step (2), add 259.4 mL of water.

3. The method for preparing colloidal gold for Helicobacter pylori antigen detection test strip according to claim 1, characterized in that: In step (3), 6 mL of the seed solution prepared in step (1) is added.

4. The method for preparing colloidal gold for Helicobacter pylori antigen detection test strip according to claim 1, characterized in that: In step (4), the flow rate of the 2% sodium citrate solution is 2 mL / min.

5. A method for preparing a Helicobacter pylori antigen detection test strip, characterized in that: The steps include: (1) Preparation of binding pad: Take the colloidal gold solution prepared above, stir with 0.2M K2CO3 solution to adjust the pH value of the colloidal gold solution to 7.8, add 5 μg / mL of Helicobacter pylori antigen to the colloidal gold solution and stir for 5 min, then add BSA with a final concentration of 0.5% and react for 20 min to complete labeling, centrifuge the labeled colloidal gold at 10000 rpm for 30 min at 4 °C, remove the supernatant and re-dissolve it with re-solution to 1 / 10 of the original concentration, and centrifuge the re-dissolved liquid at 0.5 mL / cm 2 The coating is applied to the glass fiber and dried to form a bonding pad.

6. The method for preparing a Helicobacter pylori antigen detection test strip according to claim 5, characterized in that: The formula of the reconstitution solution is: 0.2% (W / V) Tris, 0.75% (W / V) casein, 0.8% (W / V) BSA, 0.8% (W / V) Tween-20, 0.5% (W / V) sucrose, pH 7.

8.

7. The method for preparing a Helicobacter pylori antigen detection test strip according to claim 6, characterized in that: The following steps are also included: (2) Sample pad preparation: Take 10 g Triton X-100, 18 g polyvinyl pyrrolidone, 5 g surfactant S9, 18 g bovine serum albumin, and 8 mL Tween-20, dilute to 1 L with 10 mM phosphate buffer, adjust the final pH value to 8.0, and then immerse the glass fiber in it. After taking it out, dry it to make a sample pad.

8. The method for preparing a Helicobacter pylori antigen detection test strip according to claim 7, characterized in that: The following steps are also included: (3) Coating of quality control line and test line: Helicobacter pylori monoclonal antibody and goat anti-mouse IgG were coated on nitrocellulose membrane at 1.0 μg / mL and 1.25 μg / mL respectively.

9. The method for preparing a Helicobacter pylori antigen detection test strip according to claim 8, characterized in that: The following steps are also included: (4) Paste the sample pad, conjugate pad, nitrocellulose membrane and absorbent paper on the bottom plate in order, cut them into 2 mm wide pieces and assemble them in the card shell to obtain the test strip.

Images