The effectiveness of using serum separation gel blood collection tubes depends not only on the quality of the product itself, but also closely related to every step of the terminal operation. From mixing after blood collection, to waiting for coagulation, to setting centrifugation parameters and checking equipment status, every step has details worth paying attention to. Following standardized procedures is necessary to ensure that the separation gel forms a complete and stable isolation barrier between serum and blood cells.
After blood collection, mix well and wait for coagulation
After the blood collection is completed, the first operation is to gently invert the test tube. The purpose of this action is to ensure full contact between the blood and the coagulant or anticoagulant inside the tube, usually reversed 4 to 8 times. The intensity needs to be controlled. Excessive shaking may lead to hemolysis, while insufficient intensity can result in uneven mixing, affecting subsequent coagulation or anticoagulation effects.
The waiting time for coagulation is a process that is easily compressed. For blood collection tubes containing coagulants, it is recommended to wait for 8 to 15 minutes until the blood sample is completely coagulated before centrifugation. If the coagulation is not sufficient, it is easy to use the machine. After centrifugation, fibrin filaments may appear, which may block the needle during instrument sampling, leading to detection interruption or abnormal results. Ordinary tubes without added coagulants require longer clotting time, typically 1.5 to 2 hours. However, in actual clinical practice, the phenomenon of centrifugation after waiting for 15 minutes or even less than 10 minutes is quite common, which is also one of the important causes of needle blockage.
Centrifugal balancing and parameter setting
Before centrifugation, the blood collection tube needs to be symmetrically placed into the rotor to ensure weight balance. When the sample size is odd, an equal weight balance tube must be used for balancing. The centrifugal state with unbalanced weight can cause rotor deflection, which not only affects the separation effect, but may also damage the centrifuge spindle and even cause safety accidents.
The setting of centrifugal parameters directly affects the final position of the separation gel. For a horizontal centrifuge, it is recommended to centrifuge for 8 to 10 minutes and control the centrifugal force between 1800 and 2200g. The separation path of the angle centrifuge is shorter, and the time can be appropriately extended by 3 to 5 minutes to achieve similar separation effects. Special blood samples need to be processed separately: in samples with high blood lipids or hemolysis, plasma density and viscosity may change, and conventional centrifugation time may not be sufficient to achieve complete separation. It is recommended to extend the centrifugation time by 5 to 10 minutes. The centrifugal force is too low or the time is too short, and the separation gel cannot move to the correct position between the serum and blood cells; If the centrifugal force is too high or the time is too long, the separation gel may be squeezed through the cell layer.
Equipment status and temperature control
During the operation of centrifugal equipment, operators need to pay attention to whether the machine is in normal condition. If there is an abnormal vibration sound, it may be a signal of rotor imbalance, bearing wear, or motor failure, and the machine should be stopped immediately for inspection. Wait for the rotor to come to a complete stop before opening the cover. Manual braking is prohibited as sudden braking may disrupt the settling components and affect the separation effect. In addition, it is recommended to control the operating environment temperature at around 25 degrees Celsius. Excessive or insufficient temperature can affect the viscosity of blood and the fluidity of separation gel, thereby altering the actual separation behavior.
From reverse mixing to coagulation waiting, from balanced centrifugation to equipment monitoring, each step has its own reason for existence. A standardized blood collection tube and separation gel can form a smooth and dense barrier between serum and blood cells, which is convenient for direct machine detection and effectively prevents continuous contamination of serum by cellular components. Hubei Xindesheng Material Technology Co., Ltd. specializes in producing blood collection tube additives such as serum separation gel. If you need them, please feel free to contact me at any time!
Por favor verifique seu email!
