Using the right equipment always makes life easy, especially if it’s highly relevant in different applications. The centrifugal is a versatile piece of equipment used for various applications in medical laboratories and life science. When considering to get the perfect benchtop centrifuge for your lab, here are things you should consider:
- Centrifuge size and capacity
- Centrifuge speed
- Specification of rotor
- Replacement of rotor
- What type of temperature variation is required?
- Is any IVD certification required?
Benchtop Centrifuge Size and capacity
When considering a Laboratory centrifuge purchase, the bench space is significant in the lab. Therefore, it is best to choose a centrifuge whose physical footprint, tube capacity, and functionality match the bench space available. However, according to its size, there are 2 Main types of benchtop Centrifuges: mini centrifuge, micro centrifuge.
Mini Centrifuge – It has a small capacity. Its features include;
- Tube capacity of 0.5-2.0 ml.
- Fixed rotor except in few
- Low speed
- Ideal for same method and processing of fewer tubes
Micro Centrifuge – it has a medium capacity. Its features include;
- Tube capacity of about 5.0ml
- Changeable rotors and tube adapters are available.
- Some are refrigerated model
- Ideal for clinical application and much quantity using small tubes.
Specification of rotor and adapter
Some of the centrifuge models come with fixed rotors or changeable rotors. For instance, the mini centrifugal comes with a fixed rotor. That’s the rotor cannot be switched to a different type. But for models that have changeable rotor features. The rotors used depends on the application. However, some centrifugal products come with a rotor set and adapter for tube types. There are two types of rotors, fixed-angle rotors, and swing-out rotors.
Fixed Angle Rotors – these rotors are mostly used in the laboratory. Here are some of its features;
- Tubes are usually positioned at a fixed angle of 45 degrees.
- Higher rotational revolution per minute (RPM) compare to swing-out counterparts. It is best used to separate macromolecule, which tends to produce pellet and supernatant in samples. As a result of the tube positioning, they produce a fairly distingulishable phase upon physical appearance.
- Ideal for Larger capacity and high level of automation.
Swing out Rotors - here are some of its features;
- Swing out horizontally to the axis of rotation
- It operates using the adapter and buckets to put the tubes in their position.
- Rotation speed is low and, as a result, tends to produce a less efficient pellet, which appears nearly neat at the bottom.
- Suitable in cases where samples are separated based on density gradients.
- It requires constant extra maintenance and greasing at the pivot region.
The centrifuge speed is essential, depending on the application. However, it is also necessary to consider the speed setting and its accuracy. Some of the factors that affect the maximum speed are the type of rotor and tube. Therefore, it is advisable to consider them before getting a centrifuge.
The speed of a centrifuge can be classified into two types, relative centrifugal force(RCF), which is influenced by the gravitational force, and revolution per minute (RPM).
Centrifuge models exist in two types depending on the required temperature for operation. They can either be refrigerated or non-refrigerated models. The refrigerated model applies the cooling principle to protect heat-sensitive samples in the centrifuge chamber. They also have a heating feature that is above ambient chamber temperature. However, temperature control determines the size of the centrifuge. For example, the refrigerated models are large than non-refrigerated models because the refrigeration compartment occupies space and is mostly located at the side or back.
Replacement of rotor
Centrifuge models have a different method of replacing rotors. Some models require a key to replace them, while some may be difficult and require technical know-how. However, some do not require keys when replacing centrifuges rotor, which is easy.
Rate of heat removal
Every model has a different rate of decreasing the temperature of a chamber to the correct one. However, some model has a pre-cooling function. This helps to ensure the chamber temperature is well regulated before use. It is highly suitable for heat-sensitive samples.
Some centrifuges models have quick temperature variation features that enable them to adjust to the desired temperature fast. It is also best to consider this feature before getting your centrifuge.