SARS-CoV-2 detection kit

The following is a more detailed introduction to the detection principle of the SARS-CoV-2 detection kit:

Nucleic acid detection (real-time fluorescent quantitative PCR method):

1. Sample processing: The collected samples (such as nasopharyngeal swabs, sputum, etc.) are processed to release the virus nucleic acid.
2. Reverse transcription: The virus RNA is reverse transcribed into cDNA (complementary DNA).
3. PCR amplification: Specific primers are used to amplify the cDNA, and in each cycle, the DNA polymerase synthesizes a new DNA strand according to the primer sequence.
4. Fluorescence detection: During the amplification process, a fluorescent probe is added. When the probe binds to the amplification product, it emits a specific wavelength of fluorescent signal. By continuously monitoring the change of the fluorescent signal, it can be determined whether there is virus nucleic acid and the amount of virus nucleic acid.

Antigen detection:

1. Antibody binding: The detection kit contains antibodies that can specifically recognize the virus antigen. When there is a virus antigen in the sample, the antibody binds to it.
2. Detection method: Common detection methods include colloidal gold method, immunochromatographic method, etc. The antigen-antibody complex after binding will be detected through a specific color development reaction or signal generation mechanism, thereby judging whether there is a virus antigen.

In general, nucleic acid detection has high sensitivity and specificity, and can accurately detect the virus in the early stage of infection; antigen detection is relatively simple and quick to operate, but the sensitivity may be relatively low, and it may not be sensitive to cases in the later stage of infection or with a low viral load. Different detection methods have their own advantages and disadvantages, and are usually selected according to specific needs and situations in practical applications.