How can there be transparent liquid at the bottom of the test tube after the additives of blood collection tube are added?

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When we go to the hospital for physical examination, the doctor will often write out a blood test sheet. After the blood test results come out, the medical staff will judge whether there is a disease according to the analysis data. But in the process of blood drawing, many people found that a layer of transparent liquid was slightly revealed at the bottom of the blood drawing vessel. What was the matter? Is it adulterated with water? On this issue, I will give you a detailed analysis.

First of all, we need to tell you rationally that the fear of containing water at the bottom of the test tube is redundant. That layer of transparent liquid is not real water, but an anticoagulant added in advance. Although there are also dry anticoagulants in the process of application, most of them are added to the test tube with liquid anticoagulants. The common anticoagulants contained in evacuated blood collection vessels are as follows:

1Heparin sodium, heparin lithium

Heparin sodium and heparin lithium are added in the test tube, which can play an excellent anticoagulation purpose with the help of heparin, and will not interfere with blood cells, will not affect the size of red blood cells, will not cause hemolysis, and is suitable for universal biochemical determination. The artificially manufactured powdered heparin with analytical purity needs to be prepared into a solution and added into the test tube. There will be liquid.

2EDTA potassium salt

The tube is mainly filled with potassium EDTA and potassium trioxide. Under normal temperature, the blood coagulates quickly in a short time, which is not conducive to experimental detection. Adding anticoagulants can not only delay the blood coagulation time, but also promote blood coagulation. Since EDTA potassium salt is also in powder form, it will be added into the test tube after being prepared into a solution, and there will also be a little liquid inside, which will not affect the detection effect, but can promote the accuracy of the detection results, which is also a class of anticoagulants generally recommended in the market.

3Sodium citrate

An appropriate amount of sodium citrate anticoagulant is added in the test tube, which mainly depends on the aggregation of citrate and calcium substances, which can form calcium chelates to prevent blood coagulation. It is suitable for the examination of coagulation mechanism. Sodium citrate produced by many manufacturers needs to be prepared as a solution, so there will be a small amount of liquid in the test tube. If it is not dried, the liquid will always exist, and it will not interfere with blood testing, so it can be used with confidence.

Desheng Biochemical is a professional manufacturer of anticoagulants for blood collection vessels. Its series of products are in powder form. They need to be prepared into solutions when added into test tubes for drying. After drying, there will be no liquid state. If you have relevant needs, please click the website for details! I will do my best to answer your question.