Low-Speed Centrifuge vs. High-Speed Centrifuge vs. Ultracentrifuge: A Comprehensive Analysis of the Core Differences

Release time:

2025-04-14

Overview:

In a nutshell: Low-speed centrifuge: the lab’s “basic laborer,” handling the heavy-duty tasks. High-speed centrifuge: the research lab’s “all-rounder,” striking a balance between efficiency and cost. Ultracentrifuge: the “special forces” of the nanoscale world—expensive but irreplaceable.

Centrifuges are classified primarily according to their rotational speed ranges and application scenarios. Low-speed, high-speed, and ultrahigh-speed centrifuges differ significantly in terms of performance, structure, and intended use.
The following compares their core differences across six major dimensions:
I. Rotational Speed and Centrifugal Force Range

Key points:
The centrifugal force generated by an ultracentrifuge can reach up to one million times Earth's gravity, necessitating special protective design.
Low-speed centrifuges rely more on gravitational sedimentation, while high-speed/ultrahigh-speed centrifuges rely on density gradient separation.

II. Differences in Core Structure
1. Rotor Design
Low-speed centrifuge:
Primarily horizontal rotor (basket-type), with large capacity (up to 6L per unit).
The material is mostly aluminum alloy, with relatively low corrosion resistance.
High-speed centrifuge:
Primarily uses a fixed-angle rotor to reduce wind resistance.
Titanium alloy or carbon fiber rotor, resistant to high-speed deformation.
Ultracentrifuge:
Ultra-lightweight titanium alloy/ceramic rotor, requiring operation in a vacuum environment (to reduce friction-induced heat generation).
Equipped with a vacuum-sealed chamber and a liquid nitrogen cooling system.
2. Drive and Temperature Control System
Low speed: Standard motor, operates at room temperature (no cooling required).
High speed: Brushless motor + air-cooling/compressor cooling (to prevent sample overheating).
Over-speed: Maglev drive + liquid nitrogen temperature control (-20℃ to 4℃ with precise temperature regulation).
III. Comparison of Application Scenarios

IV. Safety Requirements and Restrictions

A painful lesson learned through blood and tears:
When a high-speed centrifuge is operated without being sealed, aerosols containing pathogens can spread throughout the entire laboratory!
The lifespan of ultracentrifuge rotors is strictly limited (e.g., Beckman rotors: mandatory disposal after 150 million revolutions).
V. Costs and Maintenance

VI. How to Choose?
1. Experiment requirements take priority.
Separation of red blood cells/cell debris → Low speed is sufficient.
Plasmid DNA extraction → High-speed centrifuge (12,000×g).
Exosome purification → Ultracentrifuge (100,000×g or higher).
2. Budget and Frequency of Use
The initial operating cost of an ultracentrifuge is extremely high (approximately 500 yuan per ultracentrifugation run, covering consumables and liquid nitrogen expenses), making it suitable for high-frequency research-level laboratories.
The high-speed centrifuge is a cost-effective choice, covering 80% of molecular biology experiments.
3. Space and Security
The ultracentrifuge requires a separate explosion-proof room (covering an area of 2–3 square meters).
The high-speed centrifuge can be placed next to a biosafety cabinet (which requires regular disinfection).

One-sentence summary:
Low-speed centrifuge: the lab’s “basic laborer,” handling the heavy-duty tasks.
High-speed centrifuge: a “versatile” tool for scientific research, balancing efficiency and cost.
Ultracentrifuge: the “special forces” of the nanoworld—expensive but irreplaceable.