Can coagulant tubes be centrifuged immediately

Coagulant tubes are widely used in clinical testing and biomedical research to quickly obtain serum samples. However, whether they can be centrifuged immediately after blood collection requires comprehensive consideration of various factors such as the principle of action of blood coagulants, blood coagulation time, serum quality requirements, centrifugation equipment conditions, and testing project requirements. Following the correct operating procedures and waiting for the appropriate time before centrifugation can ensure the acquisition of qualified serum samples and provide a reliable basis for subsequent testing and analysis.

The principle of action and coagulation process of coagulants

1. Mechanism of action of coagulant: The coagulant in the coagulant tube is composed of thrombin, silica powder, and other suspended liquids and powders. Its principle is to activate some coagulation factors, promote the formation of thrombin and fibrin clots, accelerate the contraction of blood clots, and achieve rapid separation of serum. The coagulant collection tube can usually coagulate blood in a short time.

blood coagulation

2. The normal coagulation process of blood and time factors: Under normal circumstances, blood flows in the blood vessels and does not coagulate. When the blood is collected into a coagulant tube, the coagulation process begins. Firstly, platelets adhere and aggregate at the wall of the coagulant tube, releasing some coagulation factors and active substances. Subsequently, both endogenous and exogenous coagulation pathways are activated, and a series of coagulation factors undergo a cascade reaction, converting fibrinogen into fibrin and forming blood clots. In a coagulant tube, although the action of the coagulant is accelerated, it still takes time. If centrifugation is performed before the blood has fully coagulated, it may lead to insufficient separation of the serum. Uncoagulated blood components can interfere with the formation of serum, causing fibrin fibers or blood cell fragments to mix in the serum, affecting the accuracy of subsequent test results.

Factors affecting immediate centrifugation

1. Serum quality: If the coagulant tube is centrifuged immediately after blood collection, there may be residual fibrinogen and its degradation products in the serum. These substances may cause interference in subsequent testing processes, such as biochemical analysis, immunological testing, etc. For example, in some enzyme activity assays, fibrinogen may bind to the enzyme, affecting the results of the enzyme activity assay. Moreover, residual blood cell fragments may also release some intracellular substances into the serum, altering the composition of the serum and leading to biased test results.

2. Centrifugal equipment and conditions: Due to incomplete coagulation, it may not be possible to separate serum and blood cells under centrifugal force, resulting in hemolysis. Hemolysis can increase the concentration of potassium ions, hemoglobin, and other substances in the serum, affecting the results of items such as electrolyte testing and liver function testing.

3. Testing requirements: For some tests that require high serum samples, centrifugation is not allowed before the blood has fully coagulated. Even a small amount of unconjugated blood components mixed into the serum may seriously interfere with the test results.

Correct operational suggestions

1. Waiting for the appropriate time: Generally speaking, after using a coagulant tube to collect blood, the blood should be fully coagulated before centrifugation. The specific waiting time can be determined according to the type of coagulant and the instructions. During the waiting process, place the coagulant tube at room temperature to avoid severe shaking or environments with excessively high or low temperatures, as these factors may affect the coagulation process.

2. Observing coagulation status: Before centrifugation, the condition of the blood in the coagulant tube can be observed to determine whether centrifugation is possible. If the blood has formed a solid clot and the serum is clearly visible without obvious flowing blood or fibrin fibers, centrifugation can usually be performed. But if it is found that the blood is still in a semi-solid state, with a lot of liquid flowing or appearing gelatinous, it should continue to wait. You can gently tilt the coagulant tube and observe the flow of blood to assist in determining the degree of coagulation.  

3. Following laboratory standard operating procedures: Each laboratory should develop a detailed SOP for the use of coagulant tubes based on their own equipment conditions, testing project scope, and quality control requirements. Operators should strictly follow the SOP for operations, including handling after blood collection, waiting time, centrifugation conditions, etc. Laboratory managers should also regularly supervise and inspect the implementation of SOPs to ensure that operators handle coagulant tubes correctly and obtain high-quality serum samples.

Product packaging

Hubei Xindesheng Material Technology Co., Ltd., as a coagulant supplier, can provide two types of products: coagulants and coagulants powder. The specifications are complete, and we offer one-stop purchasing services with pre-sales and after-sales tracking guidance. You can purchase and use with confidence. If you have purchasing intentions, please feel free to click on the website for consultation at any time!