Published: 26th Aug 2025, 13:45

You might be wondering why the title says “Spinning Microbes Right Round.” 

It is because, in a microbiology lab, when microbes take you out for a spin, it’s time to put your lab coats on and get your centrifugation tubes (TMC 119) ready! Much like a merry-go-round, a centrifuge whirls samples at high speed. It is a fundamental technique in science that allows for the rapid and efficient separation of mixtures and is widely popular for its time-efficient and highly detailed approach to sedimentation. 

But if you still ask, What is centrifugation? 

This is the only blog that won’t keep you in circles. Instead, let’s get straight to the point.

What is Centrifugation?

You know how you used a salad spinner to remove excess water from washed vegetables? You get it now. It is spun at a speed so that the water is forced away from the vegetables towards the edges. Exactly. The centrifuge also spins the mixtures at such high speeds for the heavier components to settle towards one side of the container.

Still looking for a definition? What geeks! Here’s one for you.

Centrifugation is a mechanical process that involves the use of centrifugal force to separate particles from a solution according to their shape, size, density, medium viscosity, and rotor speed.

Centrifugation is a sensitive technique for the efficient separation of substances from biological mixtures, and its efficiency is easily affected by speed, time, temperature, viscosity of medium, radius of rotation, and even the type of sample subjected to centrifugation.

Principle of the Centrifuge 

The Centrifuge principle is based on the simple science of settling, known as sedimentation. According to physics, the centrifugal force acting on a particle in a rotating system is given by:

F_c = mv²/r

Where:

• ‘F_c’ is the outward force (Centrifugal force) that pushes the particle away from the center of rotation.
• ‘m’ is the mass of the particle.
• ‘v’ is the speed of the particle.
• ‘r’ is the distance of the particle from the axis of rotation.

Due to this force, denser particles move toward the outer side (bottom of the test tube), and lighter particles stay closer to the center (top of the tube). 

What is a Centrifuge?

A centrifuge is a mechanical device that works under the principle of centrifugation and is used to spin samples at very high speeds (usually given in Rotations Per Minute) to separate samples.

A typical centrifuge has:

1. A rotor that holds the samples and rotates.
2. A Motor that drives the rotation by transforming electrical energy into mechanical energy.
3. A Control Panel that lets users set parameters for centrifugation 
4. A Chamber enclosure for safety.
5. A Lid Lock System that ensures safety and prevents spillage.

Types of Centrifugation

The technique can be modified according to the type of sample being dealt with, while the basic principle of centrifugation remains the same.

1. Differential Centrifugation

Particles sediment at rates determined by their size and density. Heavier components settle first, followed by lighter ones upon subsequent spins.

2. Density Gradient Centrifugation

Density gradient centrifugation is further classified into two subtypes:

a. Rate-Zonal Centrifugation

Particles are separated based on size and mass as they move through the gradient. Separation occurs before particles reach their isopycnic point.

b. Isopycnic Centrifugation

Particles settle down at a point in the gradient where their density matches that of the surrounding medium.

3. Ultracentrifugation

High centrifugal force allows for the separation of particles with subtle differences in mass and density. It is further divided into two types: 

1. Preparative Ultracentrifugation

It focuses on isolating and purifying components from a mixture.

2. Analytical Ultracentrifugation

It mainly focuses on measuring and analyzing particle behavior during separation.

Applications of Centrifugation

Molecular Biology:

• Isolates and extracts genetic material (DNA/RNA)
• Purifies proteins such as enzymes and antibodies

Pharmaceutical and Biotech Industries:

• Used in the production of vaccines, enzymes, and biologics
• Ensures precise separation and purification of biological materials

Environmental and Chemical Analysis:

• Separates pollutants, microplastics, and sediments from water and soil
• Aids in ecological monitoring and contamination assessment

Clinical Settings:

• Separates plasma and serum from blood samples
• Concentrates sediments in urine for microscopic examination.

Conclusion

By spinning samples at very high speeds, centrifugation applies centrifugal force to separate particles within a mixture. Heavier elements tend to move outward due to this centrifugal force acting upon them, described by the formula ​F_c = mv²/r. The centrifugation technique can be modified to separate particles in a sample based on their different sizes, densities, shapes, and viscosities. It’s a time-efficient and modern solution-based approach to separation and sedimentation, which makes it more reliable and popular in recent times.

Why Use Centrifuge Tubes (TMC119) from TM Media:

• Centrifugation Tubes by TM Media (TMC119) are made keeping in mind stringent sterility standards. 
• These tubes are sterile and autoclavable with a conical bottom. 
• Centrifugation Tubes by TM Media (TMC119) come in compact packages of 4*25, 1*100, and 20*25 with holding capacities of 50 ml per tube. 
• Centrifugation Tubes by TM Media (TMC119) tubes have an RCF Value of 17000G. 
• The Centrifuge Tubes by TM Media (TMC119) are widely used and trusted by lab technicians all over the world, as they meet the highest standards of quality and reliability.

Frequently Asked Questions (FAQs)