Centrifuge

A centrifuge separates components of a sample by applying controlled centrifugal force. It is often a preparation step rather than the final measurement: concentrating cells, clarifying a liquid, separating phases, or preparing material for another technique.

What a centrifuge is for

As a rotor spins, particles experience a force that can move them through a liquid at different rates. The result depends on the sample, particle size and density, medium, rotor, force, time, and temperature. A centrifuge does not make a separation “good” by speed alone; the protocol and the selected rotor are part of the method.

Core components

Component	Role in the workflow
Drive and control system	Spins the rotor at the selected operating conditions.
Rotor	Holds vessels and defines the available force, capacity, and geometry.
Buckets, adapters, and tubes	Match the sample vessel to the rotor.
Lid and safety systems	Help contain the rotor and support safe operation.
Refrigeration, where fitted	Controls temperature for samples that need it.

Fixed-angle rotors hold tubes at an angle and are commonly used for pelleting. Swing-bucket rotors allow vessels to swing outward during a run and can suit other separation formats. Eppendorf’s rotor overview 🔗 describes these differences. The rotor manual—not a general description—sets the compatible vessels, loading limits, and permitted operating conditions.

Use Centrifuge Rotor Selection to connect geometry, vessel, force, capacity, containment, and lifecycle requirements. RCF vs. RPM explains why a rotational speed cannot be transferred between rotor radii without conversion and method context.

What to consider before adoption

Sample and task: Identify whether the work is routine pelleting, phase separation, clarification, cell handling, or a higher-force separation.
Relative centrifugal force: Protocols should specify the intended force and time clearly. RPM alone is not transferable between rotor radii.
Rotor and vessel ecosystem: Capacity, tube formats, adapters, sealed options, and cleaning requirements can matter more than a broad instrument category.
Temperature and throughput: Consider sample stability, batch size, access pattern, and the time needed to load and unload safely.
Containment and location: The laboratory’s risk assessment should determine whether aerosols, infectious material, volatile chemicals, or other hazards require additional controls.

Routine care, calibration, and safety

Balance loads symmetrically by mass and use only compatible rotors, buckets, adapters, and vessels. An unbalanced or incorrectly assembled rotor can damage equipment and create an injury risk. Eppendorf’s centrifuge safety guide 🔗 explains the importance of symmetric loading and stopping a visibly wobbling centrifuge.

Inspect rotors, lids, buckets, and adapters according to their instructions; clean spills promptly with compatible materials; and record service or inspection activities under the laboratory’s procedure. Never infer a rotor’s permissible speed, imbalance tolerance, chemical compatibility, or replacement interval from another model.

For sample preparation before analysis, a centrifuge may feed HPLC, LC-MS, or spectrophotometer workflows.

Manufacturer context

For centrifugation, the compatible rotor, bucket, adapter, tube, and lid are part of the working system—not interchangeable accessories. The centrifuge product-family map shows how microcentrifuge, general-purpose benchtop, refrigerated or high-speed, floor-standing, and ultracentrifuge families connect to those configuration decisions. Eppendorf and Thermo Fisher Scientific provide manufacturer-context guides focused on the same relationship; always use the documentation for the installed centrifuge and rotor to confirm compatibility.

Before a purchase or method transfer

List the vessels, sample volumes, target force, temperature requirement, and containment needs before comparing instruments. Confirm that the complete configuration—not just the base instrument—supports the intended workflow. Plan for operator training, rotor inspection, decontamination, and a safe response to unusual vibration or noise.

If the shortlist crosses installation formats, use Benchtop vs. Floor-standing Centrifuge to compare throughput, loading ergonomics, bench or floor requirements, utilities, and service access without assuming that one format is inherently more capable.