In order to match the downstream POCT instrument to obtain the experimental results quickly and conveniently, there are also high requirements for the virus sample storage solution: firstly, it can inactivate the virus to ensure the safety of contacts; secondly, there are no components in the storage solution that inhibit downstream reactions to ensure the experiment Smooth progress; finally, nucleic acid extraction can be eliminated, the overall detection time can be minimized, and the efficiency of nucleic acid detection can be improved. However, not all virus transport media are suitable for downstream POCT diagnostic equipment.

At present, the newly launched "Cai Li Xing" inactivated virus nucleic acid direct expansion preservation solution can meet various conditions at the same time, perfectly matching the downstream POCT diagnostic equipment, and suitable for the one-step rapid virus nucleic acid detection system on the market. The following nucleic acid direct-expanded virus transport media are collectively referred to as "Cai Li Jian". Today, Desheng will take you to understand the direct-expanded nucleic acid virus transport media.

The characteristics of nucleic acid direct expansion virus transport media 1. Inactivate the virus: It can inactivate the virus without heat inactivating the sample to ensure the safety of contacts;

2. Nucleic acid direct amplification: after the sample is collected, nucleic acid extraction is not required and can be directly used as a template for amplification (for some downstream POCT instruments, it is necessary to add lysis solution to the sample preservation solution for amplification);

3. Non-guanidine salt components: the preservation solution does not contain guanidine salt, which does not inhibit downstream experiments such as qPCR and isothermal amplification;

4. Storage at room temperature: Viral nucleic acid can be stored at room temperature for 7 days without cold chain transportation.

Study on the inactivation effect of "Cai Li Xian" on poultry coronavirus

Under strict laboratory management practices, the SPF chicken embryo infection experiment was used to explore the effect of "Cai Li Xian" on the inactivation of IBV virus, and to observe the IBV nucleic acid detection amplification curve in the allantoic fluid, and some experimental results In the quantitative PCR experiment, it was found that the "Cai Li Jian" was very thorough in killing the virus, and the nucleic acid of infectious bronchitis virus was almost undetectable. Therefore, the "Cai Li Jian" preservation solution can effectively inactivate the virus.

Comparison of RNA Protection Ability of "Cai Li Jian"

“Cai Li Jian” can store RNA at 37°C without degradation, avoiding the degradation of nucleic acid in the sample before testing, resulting in “false negative” test results. We compared the effects of storage solutions containing guanidine salts on the market and "Cai Li Xian" stored at 37°C for 1-7 days. The results showed that there was basically no degradation of the viral nucleic acid in the "Cai Li", while the degradation rate of the viral nucleic acid in the other two virus preservation solutions gradually increased, and it was almost completely degraded by the 7th day.

"Cai Li Jian" analysis of whether downstream amplification is inhibited

Most storage solutions on the market will significantly inhibit the amplification when matched with the POCT detection instrument, causing amplification failure. The IBV was diluted gradually (10-3, 10-4, 10-5, 10-6) with "Cai Li Xian", and the two groups of experimental samples were tested by fluorescence quantitative PCR at the same time. Experimental results: The sensitivity of the two groups is the same, and "Cai Li Xian" has no obvious inhibitory reaction to PCR.

Therefore, the "Cai Li Jian" inactivated virus nucleic acid direct expansion preservation solution can not only inactivate the virus but also directly amplify the sample after lysis! So that the entire virus nucleic acid detection time is greatly shortened! It is a safe and fast new crown detection tool under the current new crown detection mode!