Journey into the World of Centrifuges: How to Choose the Device You Need?


Journey into the World of Centrifuges: How to Choose the Device You Need?

The silent yet hardest-working member of laboratories, centrifuges, are actually based on a very fundamental law of physics: Separation. This method, used since the 18th century, separates samples according to their shape, size, and density using the centrifugal force obtained from rotational motion. So, among thousands of options, which one is “the right” choice for you? Let’s choose it together, step by step.


1. The Basic Principle: How Is Centrifugation Done?

Everything begins by placing the material to be separated into pressure-resistant glass or plastic centrifuge tubes. The most critical point when placing these tubes into the device is symmetry; to ensure proper centripetal force, the tubes must be balanced opposite each other. When the device speed (RPM) is set and the process starts, radial acceleration pushes denser particles to the bottom while those with lower density rise to the top.


2. Rotor Selection: This Is the Heart of the Job

The physical design of the rotor is the most critical factor that determines how centrifugal force is applied to the sample.


  • Fixed-Angle Systems: In these structures, where tubes are typically fixed at an angle between 25° and 45°, very high speeds can be reached thanks to low aerodynamic resistance. Since particles hit the tube wall and settle to the bottom via the shortest path, they are ideal for pelleting processes.

  • Journey into the World of Centrifuges: How to Choose the Device You Need?

  • Swing-Out Systems: They have a dynamic structure; as the device accelerates, the buckets and tubes move into a horizontal position. This allows the sediment to spread homogeneously on the tube bottom and enables phases (such as serum/plasma) to be separated with a clear boundary line. It is the most reliable method for gradient separations.

  • Journey into the World of Centrifuges: How to Choose the Device You Need?


3. Speed and Force Guide by Application Area

The main factor that determines which device you should buy is what you want to separate. When making your choice, you should look at the RCF (g-force) capacity, which is linked to the rotor radius, rather than RPM (revolutions per minute).
Application Area Target Component Recommended Force (xg) Device Type
Cell Biology Living cells (Mammalian, Yeast) 200 – 1,000 xg Benchtop / Clinical
Clinical Diagnostics Blood (Serum/Plasma separation) 1,500 – 3,000 xg Clinical Centrifuge
Genomics / Mol. Bio. DNA/RNA Precipitation 12,000 – 20,000 xg Microcentrifuge
Organelle Separation Mitochondria, Lysosome 10,000 – 30,000 xg High-Speed
Proteomics / Virus Protein / Virus purification 50,000 – 150,000+ xg Ultracentrifuge
Nanotechnology Nanoparticle separation 30,000 – 100,000+ xg Ultracentrifuge


4. Cooling: When Is It a Necessity?

During centrifugation, the rotor’s friction with the air generates significant heat. If your samples are biological or heat-sensitive, cooling is not an option—it is essential.


Temperature Requirement Table

Condition Temperature Requirement Why?
Enzyme/Protein Work 2-8°C To prevent loss of activity and denaturation
RNA/DNA Isolation 4°C To stop nuclease activity
Cell Pelleting 4°C To preserve viability and slow metabolic rate
High-Speed (Ultra) Constant Temperature To dissipate extreme friction heat


Device Comparison: Refrigerated vs. Non-Refrigerated

  • Non-Refrigerated (Ventilated): Ideal and economical for chemicals, urine analyses, and robust solutions.
  • Refrigerated: Essential for sensitive R&D and genetic tests such as protein, RNA, and live cell studies. Temperature can be precisely adjusted between -20°C and +40°C.


5. Brand and Technology Comparison

Three different technology approaches that stand out depending on your needs:


Haier Biomedical: Smart and Fast Solutions

  • Ultra-Fast Cooling: Reaches +4°C from room temperature in approximately 15 minutes.
  • Smart Rotor Recognition (Auto-ID): Automatically identifies the rotor to prevent exceeding speed limits.
  • Advanced Balancing: Detects millimetric imbalances with six-axis vibration sensing.
  • Quiet Operation: Even at maximum speed, it is generally below 60 dB.


Hettich: Reliability and Flexibility

  • Wide Range: With special adapters, switching is possible from microliter tubes up to 750 ml bottles.
  • Biosafety: Offers TÜV-certified aerosol-tight rotor lids for infectious samples.
  • Tracking System: Tracks rotor lifetime (number of cycles) against the risk of metal fatigue.


Afi Groups: Ergonomics and User-Friendly Innovation

  • Click-and-Spin: Enables tool-free rotor changes in seconds with just the press of a button.
  • Interactive Panel: Features a glove-friendly touchscreen and more than 100 program memory slots.

Final Decision: If you are looking for high speed and smart safety in your laboratory, Haier; if modularity and durability are your priority, Hettich; if you work in a dynamic environment where rotors are changed very frequently, Afi Groups will be an ideal companion for you.