There are mainly two kinds of preservation solutions for virus sampling tubes

There are two kinds of virus blood collection preservation solutions widely used in the market, one is the improved virus maintenance solution based on the delivery of culture medium, and the other is the improved preservation solution of nucleic acid extraction lysate.

The main component of the former is eagle's basic culture medium (MEM) or Hank's equilibrium salt, which is added with salts, amino acids, vitamins, glucose and proteins required for virus survival. This preservation solution uses phenol red sodium salt as an indicator. When the pH value of the solution is 6.6-8.0, the solution is pink. Glucose, l-glutamine and protein are added to the preservation solution. The protein is provided in the form of fetal bovine serum or bovine serum albumin, which can stabilize the protein shell of the virus. Because the preservation solution is rich in nutrients, it is conducive to the survival of viruses, but also conducive to the growth of bacteria. If bacteria are polluted in the preservation solution, they will multiply in large numbers, and the carbon dioxide in its metabolites will reduce the pH value of the preservation solution from pink to yellow. Therefore, most manufacturers have added antibacterial agents to the formula. The recommended antibacterial agents are penicillin, streptomycin, gentamicin and polymyxin B. sodium azide, 2-methyl-4-isothiazolin-3-one (MCI) and 5-chloro-2-methyl-4-isothiazolin-3-one (CMCI) are not recommended, because these components have an impact on the PCR reaction. Because the sample provided by this preservation solution is basically a live virus, it can maintain the originality of the sample to a large extent. In the follow-up, it can not only be used for nucleic acid extraction and detection of the virus, but also for virus culture and separation. However, it should be noted that nucleic acid extraction and purification should be carried out after inactivation.

Another preservation solution is prepared based on nucleic acid extraction and lysis solution. The main components are equilibrium salts, EDTA chelating agent, guanidine salt (such as guanidine isothiocyanate, guanidine hydrochloride, etc.), anionic surfactant (such as sodium dodecyl sulfate), cationic surfactant (such as ammonium tetradecyl trimethyloxalate), phenol, 8-hydroxyquinoline, dithiothreitol (DTT) Protease K and other components. This preservation solution directly cleaves the virus, releases nucleic acid and eliminates nucleic acid decomposing enzyme (RNase). If it is only used for RT-PCR, it is more appropriate, but the lysate can inactivate the virus. This sample cannot be used for virus culture and separation.

EDTA salts (such as dipotassium ethylenediamine tetraacetate, disodium ethylenediamine tetraacetate, etc.) are recommended as metal ion chelators for virus blood collection and preservation solution, and heparins (such as heparin sodium and heparin lithium) are not recommended to avoid affecting PCR detection.