CENTRIFUGE MACHINE

 A CENTRIFUGE MACHINE

A centrifuge is a system that separates the components of a liquid or a fluids (and even gases) by centrifugal force. It is a biological instrument used to separate liquid material due to its density and weight. It does this by spinning the liquid in a container at high speed. Centrifuges are primarily used in laboratories to prepare test samples for analysis. For example, a centrifuge can be used to separate plasma from  blood. This machine is equipped with a rotor in which the samples to be prepared are placed. To explain it better, it’s like getting butter out of buttermilk. There are several types of centrifuges that have one or more associated applications. So when choosing a centrifuge, you need to pay close attention to the needs

 What Is Centrifugation?

Centrifugation is the process of concentrating  natural forces acting on all particles of different densities to accelerate the natural separation process. Separate the particles  in the test tube according to their density. Centrifugation can be done by filtration or sedimentation methods. During filtration, a mesh screen is used to retain solid components and allow  liquid components to flow through. Filtering does not work to centrifuge blood samples because the blood components are too small.

In both processes, the particles are suspended in liquid and separated in the centrifuge. Separation is done by centrifugal force pushing objects outward  toward the tip of the tube in the case of blood tubes, while spinning in a circle.

 PRINCIPLES OF CENTRIFUGATION

In essence, centrifugation is separation by sedimentation. The denser particles sink to the bottom of the container while the lighter particles remain in suspension. Centrifugation displaces particles with slightly different densities and is influenced by these four factors:

· Density of sample and solution

· Temperature and viscosity

· Particle removal

· Rotation speed

Relative centrifugal force (RCF) or G-force is the quantity acceleration acting on the sample is applied. When RCF exceeds the buoyant and frictional forces in the sample, the particles  move away from the axis of rotation and cause sedimentation.

What Is a Centrifuge Used For?

Because centrifuges are excellent at separating particles by density, they are often used in laboratory settings where it is necessary to isolate certain biological components for testing. For example, in a blood sample,  red blood cells and plasma are mixed. After centrifugation, the red blood cells are at the bottom of the tube and the plasma at the top.

Centrifugation is necessary to investigate certain components, such as separating  blood plasma for analysis, isolating DNA, and even separating  urine sediments.

 

How Does a Centrifuge Work?

The purpose of the centrifuge  is to replicate and accelerate centrifugation to separate components in a sample. Due to the forces involved, these machines have been carefully designed to operate efficiently and ensure operator safety.

The Parts of the Centrifuge Machine

In the center of the centrifuge there is a powerful motor that generates the spin. The rotor is attached to this motor, in which  the containers that contain the tubes with the material to be centrifuged rest. These containers can be rotated at a 45 degree angle (fixed angle centrifuge), a 90 degree angle (horizontal centrifuge), or no angle (vertical centrifuge). Depending on the centrifuge, the tubes can be loaded at the angle  they  rotate (the fixed angle is a good example) or  loaded into a container that is placed at a different angle when turned on. This second methodology is called oscillating bucket and is a common feature in horizontal centrifuges.

 Depending on the selected centrifuge, different control elements are available. Some centrifuges are pre-programmed for one, two, or three processing settings. Some are fully custom programmable with a digital display. Regardless of the type of control, the centrifuge will run the motor according to the settings provided at start-up. During the run, the sample in the test tubes is separated into its various components so that they are ready for analysis.

 THE DIFFERENT TYPES OF CENTRIFUGES

1. STANDARD CENTRIFUGES:

These are models  that can be used for urinalysis, stool analysis, etc. They have a  speed of between 5,000 and 15,000 rpm.

2. MICRO CENTRIFUGES:

 They are generally used for small amounts of sample, such as capillary tubes. They are used mainly to draw blood. Its speed is greater than 10,000 rpm. These centrifuges  have a compact design.

ULTRA CENTRIFUGES:

These types are very fast running centrifuges. They are primarily used for advanced analysis in specialized laboratories or research facilities. Its speed is quite high, between 50,000 and 100,000 rpm.

4. MANUAL CENTRIFUGES:

They are manually operated  by one person using a crank at a  speed of approximately 3,000 rpm. There are a variety of rotors  installed in centrifugal machines, such as: B. High-performance swing-bucket rotor, high-performance fixed-angle rotor, etc. They are used in separation and extraction.

THE CENTRIFUGE MAY HAVE THE FOLLOWING FUNCTIONS:

HEMATOLOGY: 

These include haematocrit centrifuges, which effectively determine the volume of erythrocytes in the blood. It can often handle 24 capillaries at the same time and its maximum  speed is usually 12,000 rpm.

 MOLECULAR BIOLOGY:

Centrifuges are used here, for example for DNA extraction. In this category, we may also need a refrigerated centrifuge. Refrigerated centrifuges are used to process samples that must be kept at a constant / similar temperature. That is why it is important that they work at high speeds while maintaining the same temperature. In most cases, the temperature range of these centrifuges is between 20 and 40 degrees Celsius, making them suitable for DNA or RNA analysis.

BACTERIOLOGY:

Here centrifuges are used for  cytology of fluids from various sources, for example parasitological centrifuges can help to perform parasite concentration tests.

How to Use a Centrifuge Machine

Despite the complex principles of the centrifuge, the operation of the machine itself is quite simple. To use a centrifuge:

· Insert the sample from the test tube  into one of the portals

· If necessary, insert test tubes filled with water according to the number of samples to be analyzed to maintain equilibrium

· Replace the cap and select the desired settings

· Start the centrifuge and wait for the cycle to complete  

· When the centrifuge has stopped spinning, remove the scales and samples

· Each sample is now  separated into its various components and is ready for analysis

· Know  how a centrifuge  works is key to using it properly. .

Balancing the Centrifuge Machine

When using a centrifuge, you need to balance your samples. Balancing the centrifuge machine:

· Ensuring that all tubes are filled evenly  with liquids of similar  density

· Ensuring that the masses of the tubes are within 0.1 grams of each other

· Placing tubes opposite each other in the machine to avoid gravity at the center

· If you are testing an odd number of tubes, it may not be possible to find a balance. In these cases, fill another test tube with water and adjust for density and mass.

Care and Maintenance for the Centrifuge Machine

Make sure your centrifuge is properly cared for and maintained so that it provides reliable results, is safe to use, and lasts a long time. Perform these checks regularly:

· Training – Make sure  everyone who uses the centrifuge is familiar with them. Teach all lab workers how to balance samples, adjust speeds, and take safety precautions.

· Inspection: An inspection draws your attention to  problems with the centrifugal machine. Examine components for scratches or chemicals. All are signs of use and should be repaired as soon as possible.

· Warning: While using the centrifuge, look for signs that something is wrong. If the machine wobbles, vibrates, or grinds, stop it immediately.

 Cleaning and disinfection are the key to ensuring long-term good centrifuge performance. Using a neutral cleaning solution (such as an alcohol-based disinfectant) and a soft cloth, clean the following:

· Rotors

· Rotor chamber

· Accessories

· Interior

· Keyboards

· Touchscreens