The centrifuge is an unsung companion in the busy medical laboratory, changing diagnostic processes with its sheer force and accuracy. This vital machine works by quickly spinning materials—like blood or urine—at high speeds to separate each component according to density. To ensure that patients get prompt and accurate medical help, the use of a centrifuge machine in a laboratory plays a vital role in converting raw samples into significant diagnostic information for everything from diagnosing infections and disorders to monitoring organ function.
In this article, we have explained the different types of centrifuge machines and their uses.
What Is a Centrifuge Used for?
Different laboratories use centrifuges to separate liquids, gasses, or fluids according to their density. Centrifuges are frequently used in clinical and research facilities for nucleic acid and protein purification, organelle and virus purification, and cell collection.
One of the most crucial uses of centrifuge is the component separation of whole blood. Centrifugation can also be used to obtain serum or plasma, which are required for many assays. A complete blood sample is allowed to dissolve at room temperature in order to extract serum. After centrifuging the material, the clot is removed, and a serum supernatant is left behind.
In contrast to serum, plasma is made from whole blood that hasn’t been allowed to clot and includes both clotting factors and serum. A full blood sample is drawn into tubes that have been treated with anticoagulants in order to extract plasma. The plasma supernatant remains after cells are removed through centrifugation.
How Do Centrifuges Work?
As far as we know, centrifuges are used in medical laboratories to separate materials with similar densities or when a dissolved solution contains insoluble particles.
The sedimentation principle underlies the functioning of all centrifuge types. Specifically, the rotor’s acceleration generates a centripetal force that acts on the rotor and centrifuge tubes. As a result, the lighter particles in the tubes flow toward the center, forcing the denser materials to move outward in a circular motion.
Occasionally, several particles adhere to the bottoms of the centrifuge tube. The clear solution is referred to as the supernatant, and these particles are termed pellets.
A centrifuge is usually set up to rotate at a specific rotational speed or revolutions per minute (rpm). Nevertheless, despite having different diameters, two rotors can spin at the same speed. As their radii and angular momentums differ, these rotors will also have different accelerations. Another factor is the rotor’s size. Relative Centrifugal Force (RCF) is the recognized standard unit because of this.
Principles of Centrifugation
Using a centrifuge, liquid-sustained particles may be separated based on their size, density, medium viscosity, and rotor speed.
Particles in a solution that are denser than the solvent will sink due to gravity, while less dense particles will float to the top.
The centrifugal force produced when the rotor revolves around its central axis moves particles away from the rotational axis. If the centrifugal force is greater than the buoyant forces of the liquid medium and the frictional force the particle creates, particles will sediment.
How Do Different Types of Centrifuges Work?
Some different types of centrifuges are commonly used in laboratories.
Microcentrifuge
- As their name implies, these are quite small and occupy minimal workspace on the workbench.
- They are frequently used in biological applications and are suitable for use with tiny tubes (up to 2.0 ml).
- Some of these include a separate rotor or rotor adaptors that can fit tubes of different sizes.
- These are employed in the microfiltration of small aqueous samples as well as the holding and pelleting of nucleic acids and proteins from solutions.
Refrigerated Centrifuges
- These centrifuges are used for samples that require constant-temperature storage. They must run as quickly as possible while maintaining a constant temperature.
- Refrigerated centrifuges, with a temperature range of -20 to -40 degrees Celsius, are ideal for examining DNA, RNA, PCR, and antibodies.
- Refrigerated centrifuge chambers are sealed according to the material requirements.
- They come in a variety of forms, including fixed angle, swing bucket, and both.
- There are distinct applications for small and big-capacity chilled centrifuges.
- Yeast cells, chloroplasts, and other materials that sediment quickly are commonly collected using them.
High-Speed Refrigerated Centrifuges
- These centrifuges can create a significant amount of force, making them useful for removing larger cell organelles, proteins, microorganisms, and debris from cells.
- There are several sizes and holding capacities accessible for high-speed refrigerated centrifuges.
Ultracentrifuges
- These centrifuges may produce an incredible 1,000,000 g of acceleration.
- Users of ultracentrifuges can benefit from the minute distinctions between molecules, such as proteins and nucleic acids, that allow for separation.
Ultracentrifuges come in two different types:
Preparative Ultracentrifuges
- These are most frequently used to remove denser particles for pellet collection, separate particles based on respective densities, and clarify particle-containing solutions.
- They assist in deprotonating physiological fluids for the study of amino acids and in isolating macromolecules and lipoprotein components from plasma.
- A preparative ultracentrifuge can be equipped with varied rotor types that spin multiple samples at different angles and speeds.
Analytical Ultracentrifuges
- These include an optical detecting device based on light, allowing for real-time sample rotation monitoring.
- In fact, the sedimentation process is visible to users. As the sample concentrates with increasing centrifugal force, they can observe it.
- The light absorption system, the alternate Schlieren system, and the Rayleigh interferometric system are a few of the optical systems that are used in the analysis.
Conclusion
Although this article focuses on the uses of a centrifuge in a medical laboratory, various types of centrifuges are intended for use in space and human applications, as well as large-scale industrial applications. This information will help you better understand the different types of centrifuges that scientists and lab professionals use.
If you want to purchase high-performing centrifuges for your medical lab, connect with NE LABSystems—we have a wide collection of medical products for you. Explore now.