Chemiluminescence IVD Industry Technical Responsibility (Part 2)

In the last issue, we briefly introduced the principles, advantages and disadvantages of chemiluminescence immunoassays.
Let's talk about the differences between the three classifications in detail
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01 Direct chemiluminescence immunoassay Direct chemiluminescence immunoassay (CLIA) is an immunoassay method that directly labels antigens or antibodies with chemiluminescent agents
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The commonly used chemiluminescent substances for labeling are acridinium ester compounds - acridinium ester (AE), which are effective luminescent labels
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It emits light by starting the luminescent reagents (NaOH₂, H₂O₂), and the strong direct light emission is completed within one second, which is a fast flashing light
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 Acridine ester is used as a marker for immunoassay, and its chemical reaction is simple, fast, and does not require catalyst; the competition method is used to detect small molecule antigens, and the sandwich method is used to detect macromolecular antibodies, which has less non-specific binding and low background; Binding does not reduce the amount of light produced, thereby increasing sensitivity
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 CLIA development mainly includes the following steps: Magnetic beads coating antibody (the following steps need to be optimized according to different projects) BeaverBeads® Streptavidin streptavidin magnetic beads utilize the high specific binding ability of streptavidin and biotin , BeaverBeadsRStreptavidin can be specifically combined with biotin-labeled high-purity antibody/polypeptide molecules or nucleic acid molecules, and has the effect of cascade amplification.
It is a universal solid-phase medium material with labeling and capturing properties
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 Depending on the particle size, the product can be used in immunodetection, probe capture, cell sorting and other fields, especially for chemiluminescence immunodiagnosis
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Related Beaver products are as follows: BeaverBeads® NHS Bioligand Rapid Coupling Magnetic Beads Magnetic beads modified with NHS groups on the surface, which can form stable peptide bonds with proteins and other molecules with primary amine groups for affinity purification Or analytically detect antibodies, antigens and other biomolecules
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 Compared with the traditional carboxyl and amino magnetic beads, there is no need to use EDC/NHS or glutaraldehyde for activation in advance.
It is only necessary to dissolve the primary amino group-containing biological ligand in the coupling buffer, and mix the protein solution with NHS at room temperature.
The biological ligands can be covalently coupled to the magnetic beads by mixing magnetic beads, and the coupling efficiency can reach more than 90%; the pH of the coupling system is 5-9.
The related beaver products are as follows: BeaverBeads®Polymer polymer magnetic beads have fast Magnetically responsive superparamagnetic, good dispersibility, uniform particle size, extremely low non-specific adsorption and abundant binding sites
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Under the action of specific reagents (such as EDC/NHS), various biological ligands (proteins, peptides, oligonucleotides, drug molecules, etc.
) are covalently coupled to the surface of magnetic beads
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Commonly used in detection, capture and other experiments
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Relevant beaver products are as follows: Beaver Magnetic Seprator stand A series of special magnetic separation tools of different specifications designed for manual operation or high-throughput automation of rapid separation of magnetic beads, suitable for antibody purification, immunoprecipitation, immunocoagulation Precipitation, cell sorting, nucleic acid isolation and other related experiments
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Relevant beaver products are as follows: acridinium ester-labeled antibody ①Pretreat 0.
5mg of antibody with labeling buffer (0.
1M pH7.
4 PB); ②Add 0.
1mg of acridinium salt to the pretreated antibody, and place in constant temperature shaking Incubate overnight in the dark in the bed; (3) After the labeling is completed, purify the conjugate, add a protein protectant such as BSA, and store at 4°C in the dark
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 Acridine esters are a class of chemical substances that can be used as chemiluminescent markers.
Acridine esters or acridine sulfonamide compounds can emit light in dilute alkaline solution with H₂O₂, no catalyst is required, and the luminescence system is simple
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 At the same time, the luminescence of these compounds is of a flash type, and the emitted light intensity reaches the maximum at about 0.
4s after adding the luminescence starting reagent, and the half-life is about 0.
9s, which is very time-saving
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 Based on the above characteristics, in order to enhance the chemiluminescence intensity of acridine esters or acridine sulfonamide compounds, some surfactants such as triton x-100 and tween-20 are added to the luminescence initiation reagent
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The related products are as follows: On-machine detection experiment ① Dilute the magnetic bead coating and the acridine ester marker to the working concentration to prepare reagents; ② Set up an automatic chemiluminescence instrument, load the reagents, and load the standard quality control samples on the machine respectively , select the corresponding item, and perform the test directly; ③The remaining time of the test and the test result will be displayed on the screen.
You can view the historical data through "Query", and click "Export" to save the data as an Excel format file
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 02 Indirect chemiluminescence immunoassay Indirect chemiluminescence immunoassay, also known as chemiluminescence enzyme immunoassay, uses enzyme-labeled biologically active substances to carry out an immune reaction, and the enzyme on the immune complex acts on the luminescent substrate, and emits light under the action of the signal reagent.
Luminescence signal tester for luminescence test
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Commonly used labels are HRP and AP, and their substrates are luminol and AMPPD, respectively
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 1 Specific process flow: Add the antibody-coated magnetic particles to the sample, wash the standard, add the enzyme-labeled antibody/biotinylated antibody, wash the plate, add streptavidin HRP, wash and add the substrate solution to test the luminescence signal (for plate type luminescence, please refer to Elisa Operation mode) Chemiluminescence (ECL) substrate related products: 03 Electrochemiluminescence immunoassay Electrochemiluminescence immunoassay (ECLIA) is the product of the combination of electrochemiluminescence and immunoassay, and is one of the labeling immunoassay technologies
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 There is an electrochemically induced specific chemiluminescence reaction on the electrode surface, and Ab is labeled with the electrochemiluminescent agent ruthenium terpyridine [Ru(bpy) 3 ] 2+, through Ag-Ab reaction and magnetic bead separation technology, according to ruthenium terpyridine in The light intensity emitted from the electrode is used to quantify/qualify the Ag or Ab to be measured
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 ELIA is highly sensitive, up to Pg/ml or pmol; strong specificity, good repeatability, CV<5%; wide assay range; stable reagents, non-toxic, non-polluting, and long validity period
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Simple operation and easy automation
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 Ruthenium Terpyridine: Tripropylamine (TPA): If you need to inquire about beaver magnetic beads, you can contact Dongray Technology to solve your problems
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