pH range of virus sample preservation solution

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Before the new crown pandemic, many people may be relatively unfamiliar with the virus and virus detection, but now it can be said that everyone knows and knows about virus detection. However, not everyone may know the virus sample preservation solution in the nucleic acid sampling tube. This article mainly introduces the pH range of the preservation solution.

The pH value of virus preservation solution or sample preservation solution is an important basic parameter, which provides a suitable pH value for virus nucleic acid samples. Nucleic acids generally dissolve better in a neutral to weakly alkaline environment, and the pH value of the virus preservation solution is usually in the range of 6.5-8.5. The nucleic acid of the new coronavirus is RNA. Compared with DNA, it is easier to dissociate into the aqueous phase when it is neutral to weakly alkaline. Therefore, when the nucleic acid is separated and purified by Tris balanced phenol (pH=8.0), the RNA is in the aqueous phase and the DNA is in the organic phase.

The pH range of the sampling tube virus preservation solution on the market may be different, but the difference is not large. When pH=7 and pH=8, the hydrogen ion (or hydroxide) concentration is low, and the difference is small, but when the pH is 1 and 2 or 13 and 14, the difference is relatively large. At the same time, when the pH is 8, the hydroxide concentration is small, 0.9 times the acid will bring the pH down to 7, but it takes 9 times the alkali to raise the pH to 9. Therefore, the preservation solution needs to be sealed when stored, which may absorb too much acidic CO2 in the air, resulting in a decrease in pH.

When the pH value is 7, it means that the hydrogen ion or hydroxide ion concentration in the system is one in ten million (the pH value or pOH value is the negative logarithm to the base of 10 of the corresponding ion concentration, and the sum of the two is in 14 at 25 degrees). When the pH is 8, the pOH is 6 and the OH- concentration is 10 parts per million. At another 25 degrees, the pH of neutral water is 7, and when the temperature rises to 100 degrees, it is 6. The ultrapure water used in Desheng's preservation solution has a pH slightly lower than 7. Weak alkaline buffer salts will be added to adjust the pH to above 7.5 to meet the preservation of nucleic acids.

In addition, when the virus preservation solution is put into the sampling tube in the tank, the workshop environment and sterilization conditions will also affect the pH value. The long bacteria will reduce the pH value. The higher the sterility level, the less the pH value will change.

In the production of the preservation solution, in order to keep the pH value of the system stable, a buffer salt component will be added, which has a buffering effect on the change of pH, and a small change will not affect the normal operation. Desheng is a manufacturer of biochemical reagents. It has rich experience in R&D and production of virus sample preservation solutions and is worthy of the market's trust!