How to select the appropriate method for extracting DNA and RNA from whole blood?

Extracting DNA and RNA from whole blood is a basic work. The quality of extracted DNA and RNA has a direct impact on the following experiments and analysis. There are a lot of methods to choose. How to choose the most suitable method becomes the most difficult thing for many people to do before the experiment begins. We analyze the most suitable experimental method from two aspects.

I. Collection and preservation of whole blood and extraction of DNA.

A. Use the blood collection with anticoagulant, the anticoagulant generally has EDTA and heparin, EDTA is better, will not affect the following reaction, if there is no blood collection, you can also add anticoagulant EDTA, prepared 0.04 M of EDTA solution in advance, every 5 ml of blood added 0.4 ml of EDTA solution, and then upside down to mix. The shorter the storage time, the higher the quality of the extract, it is best to extract within 2 months.

B. Selection of DNA extraction methods: The whole blood extraction kit generally has centrifugal column and solution type , the principle and steps are basically the same. Although the company introduced N multi-model, people do not know how to choose, but from the principle and operation steps, the basic is centrifugal column and solution type two. Generally speaking, the purity of centrifugal column (DP1801) is higher, but the amount of treatment is small (0.1-1ml), the yield is slightly lower; the yield of solution (DP2101 or DP2201) is larger (1-10ml) than that of centrifugal column. In general, the blood sample of a hospital is more than 2ml, and the solution method is generally selected for extraction. Only by trying can we know that the price of imported products is very expensive. After continuous experimental optimization, whole blood genome DNA extraction kit DP2101 or DP2201 initiated the third generation of technology, does not need protease K digestion, imports are to rely on protease K ah (this product uses purified chemical reagent cracking , DP2101 or DP2201 reduced the troubles and digestion time of protease K, and the extraction quantity and stability were better.

C. How anticoagulant (coagulation blood) be extracted? The answer is yes and it is easy to extract. There is no difference between the extraction effect and anticoagulation. Non-anticoagulant extraction products are few, and at present, there are many faithful users in the clotting blood genome DNA extraction kit.

II. how to extract the whole blood RNA?

What are the factors affecting RNA degradation during a and whole blood RNA extraction?

A.RNA enzymes are very abundant in whole blood. RNA is easy to degrade without protection. What are the unprotected state RNAs, such as the lysate of red blood cells, which is a low-concentration, balanced salt solution that does not inhibit the RNase component, when RNA is unprotected, and when DNA enzymes digest RNA is unprotected, and at this time does not inhibit the RNase component.

B. what kind of extraction method is better?

When we choose methods, we should tend to have a full protection for RNA. The general method is to use erythrocyte lysate to lyse red blood cells, then extract nucleic acid from white blood cells, but also through the digestion of DNA enzymes to remove DNA, this is not the best method, there are many factors in the process of RNA degradation. So direct lysis is the best way to quickly add the collected blood to three times the volume of lysate RLS – RP4001 blood (liquid sample) total RNA rapid extraction kit (centrifugal column type) of lysate, quickly reverse mixing. Lysate RLS contains a strong protein denaturant, which can denature protein rapidly. It is RNase denatured and cannot degrade RNA. The cleaved mixture can also be transported to avoid RNA degradation, which is a recommended method for RNA transport and extraction by SANLI Medical.