A centrifuge is a cornerstone of laboratory equipment, essential for separating mixtures of different densities and preparing samples for analysis. Whether you’re setting up a new lab or upgrading your current equipment, choosing the right centrifuge can significantly impact your workflow, results, and budget. This guide will walk you through key considerations, types, features, and practical tips to help you make an informed purchase.
For a comprehensive overview of essential lab equipment and buying considerations beyond centrifuges, check out our Ultimate Lab Equipment Buying Guide.
Setting up a new lab? Get practical advice in our guide to choosing the right lab equipment for startups.
Understanding Centrifuges and Their Applications
Centrifuges use rapid spinning (rotational force) to separate components within a sample based on density. In laboratory and industrial settings, they are used for a wide variety of applications, including:
- Blood and plasma separation (clinical labs, hospitals)
For recommendations on essential microscopy equipment in clinical labs, read our Best Clinical Lab Microscopes guide.
- DNA/RNA extraction (molecular biology, genetics)
- Cell harvesting and purification (biotech, research)
- Protein isolation (biochemistry)
- Urine and stool analysis (clinical diagnostics)
- Industrial processing (e.g., separating cream from milk, wastewater treatment)
- Viral and nanoparticle purification (advanced research)
For efficient sample preparation before centrifugation, explore the Best Homogenizers for Food Science & Biotech Labs.
The right centrifuge ensures efficient, safe, and reliable results for your specific application.
Types of Centrifuges and Their Best Uses
Selecting the correct centrifuge type is the first step in the buying process. Here are the main categories, with typical applications for each:
1. General Purpose/Standard Centrifuges
Versatile units ideal for a wide range of samples such as urine, blood, and cell suspensions. Common in clinical and research labs for routine tasks.
2. Microcentrifuges
Designed for small sample volumes (0.2–2 mL), such as those used in DNA/RNA minipreps, PCR, and protein work. High speeds and a compact footprint make them perfect for molecular biology.
If PCR is part of your workflow, don’t miss our picks for the Best PCR Machines for Clinical & Diagnostic Labs.
3. Ultracentrifuges
Used for advanced research requiring extremely high speeds (up to 100,000 rpm). Suitable for separating viruses, nanoparticles, organelles, and macromolecules.
4. Clinical Centrifuges
Tailored for routine clinical tasks like blood and urine sample processing. Typically lower speed, optimized for standard tube sizes (e.g., 3–15 mL).
5. Specialized Centrifuges
- Cell Washers: Blood bank compatibility testing, antiglobulin tests.
- Hematocrit Centrifuges: Measuring erythrocyte volume fraction.
- PCR Strip Centrifuges: Spinning PCR strips for molecular protocols.
Key Factors to Consider When Buying a Centrifuge
Before making a purchase, assess your needs using these critical criteria:
1. Sample Volume and Throughput
Curious about leading brands for lab balances? Check out our comparison: Ohaus vs Mettler Toledo Balances. Learn the differences between balance types in our Analytical vs Precision Balances article.
- How many samples will you process at once?
- What is the typical sample volume?
- Do you need to process large batches or single tubes?
For tips on selecting the right balance for accurate sample measurement, see our Analytical Balances Guide.
2. Speed and Force Requirements
- Centrifuges are rated by RPM (revolutions per minute) and RCF (relative centrifugal force, x g).
- Match speed and force to your application (e.g., higher speeds for DNA extraction, lower for blood separation).
3. Tube, Bottle, or Plate Compatibility
- Check the size and type of containers your protocols require.
- Ensure the centrifuge accommodates your preferred tubes, bottles, or microplates.
4. Temperature Control
- Refrigerated Centrifuges: Essential for temperature-sensitive samples (e.g., proteins, nucleic acids).
- Ventilated/Non-refrigerated Centrifuges: Suitable when temperature is not a concern.
For recommendations on the best models, see our list of Top Refrigerated Centrifuges for Research & Clinical Labs.
5. Rotor Type and Flexibility
- See the comparison table below for details.
6. Space and Configuration
- Benchtop Centrifuges: Compact, suitable for most labs with limited space.
- Floor-standing Centrifuges: Higher capacity and speed, but require more floor space and may need reinforced floors or special installation.
Not sure whether to choose a portable or benchtop model? See our detailed comparison: Portable vs Benchtop Centrifuges.
7. Additional Features
- Programmable controls and digital displays
- Safety features (e.g., lid lock, imbalance detection)
- Noise reduction
- Timer functions and acceleration/braking controls
- Self-balancing rotors
- Autoclavable accessories
8. Regulatory and Compliance Needs
-
Some clinical or pharmaceutical applications may require compliance with specific standards (e.g., GMP, medical device regulations).
Rotor Comparison Table
| Rotor Type | Description | Best For | Pros | Cons |
|---|---|---|---|---|
| Fixed Angle | Tubes held at set angle (usually 15–45°) | Rapid pelleting, cell harvesting, microvolumes | High speed, compact | Limited to smaller volumes |
| Swinging Bucket | Tubes swing to horizontal during spin | Gradient separations, larger volumes | Gentle separation, flexible | Lower max speed than fixed |
| Vertical | Tubes vertical during spin | Isopycnic separations (e.g., DNA gradients) | Fast, efficient separation | Specialized, less common |
| Specialty (e.g., PCR) | Designed for specific protocols or tube types | PCR strips, hematocrit, blood banking | Protocol-specific, precise | Limited flexibility |
Tip: Consider whether you need interchangeable rotors for versatility, and check rotor compatibility with your centrifuge model.
Safety Features and Best Practices
Modern centrifuges come with a variety of safety features. Look for:
- Automatic lid locking during operation
- Imbalance detection and automatic shutoff
- Rotor recognition systems (to prevent overspeed)
- Noise reduction or soundproofing
- Emergency stop functions
- Autoclavable rotors and accessories for sterilization
Regulatory Note: For clinical, pharmaceutical, or regulated environments, ensure your centrifuge meets required standards (e.g., ISO, GMP).
Installation and Space Considerations
- Benchtop models are ideal for limited space; ensure your bench can support the centrifuge’s weight and vibration.
- Floor-standing models require more space and may need reinforced flooring.
- Allow for adequate ventilation, especially for refrigerated or high-speed units.
- Consider noise levels if the centrifuge will be used in shared or open spaces.
- Ensure access to appropriate electrical outlets and, if needed, backup power.
Troubleshooting and Common Mistakes
Avoid these pitfalls for optimal performance and safety:
- Imbalance: Always balance tubes by weight before running; even slight differences can damage the rotor or cause accidents.
- Overfilling: Do not exceed tube or rotor capacity.
- Improper tube use: Only use tubes and inserts compatible with your rotor to prevent breakage or leaks.
- Ignoring maintenance: Clean rotors regularly, inspect for corrosion or cracks, and calibrate as recommended.
- Bypassing safety features: Never open the lid while the rotor is spinning; wait for a complete stop.
Centrifuge Operation and Maintenance Tips
- Place the centrifuge on a stable, level surface.
- Balance all samples and use matched tubes.
- Follow the manufacturer’s cleaning and maintenance schedule.
- Train all users on proper operation and safety protocols.
- Keep a log of maintenance and calibration.
Quick Reference Checklist: Choosing Your Centrifuge
- What is your primary application (clinical, research, industrial, etc.)?
- What sample volumes and throughput do you need?
- What speed/force (RPM/RCF) does your protocol require?
- What tube, bottle, or plate types will you use?
- Do you need temperature control (refrigeration)?
- Which rotor type(s) best suit your applications?
- How much space do you have (benchtop or floor-standing)?
- What safety and regulatory features are required?
- What is your budget, including maintenance and consumables?
- Do you need additional features (programmable controls, noise reduction, etc.)?
Conclusion
Choosing the right centrifuge involves understanding your laboratory’s specific needs and matching them to the appropriate equipment. By considering sample type, volume, speed, rotor options, space, and safety, you can invest in a centrifuge that will serve your lab reliably for years to come.
Call to Action
Have questions or need a recommendation? Contact our team for expert guidance or browse our full range of centrifuges to find the perfect fit for your lab.