Single-chain antibody and application thereof of single-chain antibody for detecting phosphorothioate pesticide residues
A single-chain antibody and antibody heavy chain technology, applied in anti-animal/human immunoglobulin, application, fungi, etc., can solve multi-component parallel detection with single detection spectrum, high cost, and inability to realize pesticide residue analysis and other issues, to achieve the effects of cost reduction, high sensitivity, and good cross-reactivity rate
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0027] Embodiment 1, the preparation of recombinant single-chain antibody
[0028] 1. Synthesis of universal haptens of phosphorothioate compounds and preparation of artificial antigens
[0029] 1. Dissolve chloroacetic acid (945mg, 10mmol) with 10mL deionized water, add equimolar amount of sodium hydroxide to obtain sodium chloroacetic acid saline solution; Dissolve salt (1.75g, 10mmol) in a 50mL round-bottomed reaction flask. After heating up to 80°C, add sodium chloroacetate solution dropwise for about 30 minutes, stir magnetically, and terminate the reaction after about 6 hours; Cool to room temperature, acidify with an equimolar amount of hydrochloric acid, extract three times with dichloromethane, combine the organic phases, dry over anhydrous sodium sulfate, and obtain a pale yellow oily liquid by column chromatography. The universal hapten of the phosphorothioate compounds obtained, abbreviated as H2, is shown in formula (I).
[0030]
[0031] 2. The hapten synthe...
Embodiment 2
[0057] Embodiment 2, the preparation of soluble antibody
[0058] 1. Transformation of expression strains
[0059] 1. Streak the expression strain HB2151 on 2×YT solid medium and cultivate overnight at 37°C. Pick a single clone and culture it in 5mL 2×YT liquid medium overnight at 37°C with shaking at 180rpm. Then take 100 μL of the bacterial solution and inoculate it into 10 mL of 2×YT liquid medium, and culture it at 37°C with shaking at 180 rpm until OD 600nm ≈0.3~0.5, the HB2151 strain of the right period was prepared.
[0060] 2. Spread the positive strains on the SOBAG plate and culture overnight at 37°C. The next day, submerge the plate with 3mL 2×YT-AG liquid medium, use a spreader to scrape off the colony, add it to 50mL 2×YT-AG liquid medium, and shake it in a water bath at 37°C until OD 600nm ≈0.5. Take out 5mL and inoculate it into fresh 50mL 2×YT-AG medium, then add 5mL with a titer of about 10 12 The pfu helper phage M13KO7 was incubated at 37°C for 45 minu...
Embodiment 3
[0074] Example 3, Functional Detection of Antibodies
[0075] 1. Detect the binding ability of antibody and antigen
[0076] 1. Using indirect uncompetitive (indirect uncompetitive) ELISA method to determine the optimal working concentration of the obtained scFv single-chain antibody and coated antigen through square matrix titration test. Determine the optimum working concentration of antibody and antigen by square array test method, OD 450nm The value is about 1.0, and the concentration combination with less amount of antibody and antigen is the optimal working concentration of antibody-antigen. The coating antigen prepared in Example 1 was used as the coating antigen. The results showed that the optimal working concentration of the antibody was 1:6,400 dilution concentration, and the optimal working concentration of the antigen was 10 μg / mL.
[0077] The basic operation of the ELISA method is as follows:
[0078] 1) Coating: Coat the enzyme-linked reaction plate with se...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More 