Determine the centrifuge speed
Understand the sample properties:
Sample composition: Samples with low adhesion are easy to settle and separate, while samples with strong adhesion are not easy to settle and separate.
Specific gravity difference of each component of the sample: large specific gravity difference is easy to settle and separate, while small specific gravity difference is not easy to settle and separate.
Particle size: large particles are easy to settle and separate, while small particles are not easy to settle and separate.
Viscosity: liquids in the sample with low viscosity are easy to settle and separate, while liquids with high viscosity are not easy to settle and separate.
Choose according to the purpose of the experiment:
Laboratory centrifuges generally require high-speed centrifuges (greater than 5000r/min), which are suitable for small-capacity angle rotors.
If the experiment requires a higher speed, such as plasmid DNA extraction, cDNA extraction, protein extraction, etc., you can choose a high-speed centrifuge or even an ultracentrifuge, which can reach a speed of 12000rpm-15000rpm or even higher.
Refer to the equipment manual:
Different models and brands of centrifuges have different speed ranges and performance parameters. It is recommended to refer to the equipment manual to determine the appropriate speed.
Determine the separation time
Consider the properties of the centrifuge material:
The properties of the centrifuge material will affect the setting of the centrifuge time. Suspensions that are easy to precipitate may require longer centrifugation times, while diluted solutions may require relatively shorter centrifugation times.
Combined with the centrifuge speed:
The faster the centrifuge speed, the shorter the centrifugation time can be. However, too high a speed may cause sample overflow or centrifuge tube rupture, so it is necessary to adjust it while ensuring safety.
Meeting experimental requirements:
The setting of centrifugation time also needs to consider experimental requirements. In order to obtain better separation effect, it is sometimes necessary to perform multiple centrifugation treatments or extend the centrifugation time.
Adjustments in actual operation:
In actual operation, the best centrifugation time can be determined through experiments. You can first set a preliminary centrifugation time, then observe the separation effect, and then adjust it as needed.
Precautions
Ensure safe operation:
When setting the centrifugation time, avoid setting it too long or too short to prevent safety problems.
Pay attention to the maintenance and care of the centrifuge:
Clean the centrifuge chamber and rotor regularly, and check the operating status of the equipment. If any abnormality is found, it should be handled in time.
Follow laboratory regulations
Follow the laboratory regulations and safety operating procedures during operation to ensure the accuracy and reliability of the experimental results.
Determining the speed and separation time of the centrifuge is a process that comprehensively considers factors such as sample properties, experimental purpose, and equipment performance. The best separation effect can be achieved through reasonable settings and adjustments.