Application of EDTA, Tris and Virus Transport Media in virus detection

In an environment where the new crown virus is raging around the world, it is self-evident that how to quickly check and isolate positive infections can play a role in controlling the epidemic. In the current popular specimen collection and processing methods, EDTA, Tris, and Virus Transport Medias play an important role in different stages. Here is a brief review.

Nasopharyngeal swab: The sampler gently holds the person's head with one hand, inserts the swab into the other, inserts the swab through the nostril to enter, and slowly becomes deeper along the bottom of the lower bridge of the nose. Because the nasal tube is curved, do not use excessive force to avoid traumatic bleeding. When does the tip of the swab reach the back wall of the nasopharyngeal cavity, gently rotate it once (if a reflex cough occurs, please wait a while), then slowly take out the swab and dip the tip of the swab into the 2-3ml virus Test tube of preservation solution (or isotonic saline solution, tissue culture solution).

Stool specimen: Take 1ml of sample treatment solution and take a sample of approximately one size. The stool specimen treatment solution can be prepared in the laboratory: 1.211g tris, 8.5g sodium chloride, 1.1g anhydrous calcium chloride or 1.47g water containing crystals of calcium chloride, dissolved in 800ml deionized water. Centrifuge at 8,000 rpm for 5 minutes, absorb the supernatant and save it for use.

Anal swab: Gently insert a sterile cotton swab into the anus to a depth of 3-5 cm, then gently rotate and pull it out, immediately put the swab into a 15ml screw cap sampling tube containing 3-5ml Virus Transport Media, discard the tail and Tighten the tube cap.

Blood sample: It is recommended to use a vacuum blood vessel containing EDTA anticoagulant to collect 5ml blood sample. Nucleic acid extraction should be carried out in whole blood or plasma according to the type of nucleic acid extraction reagent. For plasma separation, the whole blood should be centrifuged at 1,500 to 2,000 rpm for 10 minutes, and then the supernatant should be collected in a sterile plastic tube with a screw cap.

Serum specimen: Collect 5 ml blood specimen collection tube with vacuum negative pressure blood. Place the specimen at room temperature for 30 minutes, centrifuge at 1,500-2,000 rpm for 10 minutes, and collect the serum in a sterile plastic tube with a screw cap. Other materials: Collect in a standardized way according to design requirements.