The Comprehensive Guide to Centrifuge Tubes

Centrifuge tubes are indispensable tools in modern laboratories, enabling the separation of samples by density through high-speed spinning. Widely used in scientific research, medical diagnostics, and industrial processes, these tubes play a critical role in applications like DNA extraction, cell culture preparation, and blood component isolation.

However, selecting the right centrifuge tube—whether plastic or glass, sterile or reusable—requires understanding their materials, compatibility, and safety protocols.

We hope this guide will give you an in-depth understanding of the fundamentals of centrifuge tubes and how to optimize their use in the laboratory.

The primary function of centrifuge tubes is to facilitate the isolation of specific constituents within a sample. During centrifugation, rapid rotation generates relative centrifugal force (RCF), which induces denser particles (e.g., cells, proteins, or precipitated solids) to migrate toward the bottom of the tube, forming a pellet. Less dense components, such as supernatants or purified solutions, remain suspended or layered above. This physical separation relies on Stokes’ law, where particle sedimentation velocity depends on particle size, density differentials, and applied RCF. Modern centrifuges allow precise control of speed, time, and temperature to optimize separation efficiency for diverse applications.

Centrifuge tubes are integral to numerous scientific and medical workflows. In molecular biology, they are employed for DNA/RNA extraction, where centrifugation isolates nucleic acids from lysed cell mixtures. In cell culture, conical tubes enable the pelleting and resuspension of adherent or suspension cells. Clinical diagnostics rely on specialized blood collection tubes containing anticoagulants or gel barriers to separate plasma or serum from whole blood during centrifugation. Additionally, these tubes are utilized in protein purification, wastewater analysis, and pharmaceutical research, underscoring their versatility across disciplines.

Plastic centrifuge tubes, predominantly fabricated from ​polypropylene (PP) or ​polycarbonate (PC), dominate modern laboratories due to their versatility and cost-effectiveness.

Polypropylene tubes exhibit exceptional chemical resistance to acids, bases, and organic solvents, alongside thermal stability (-80°C to 135°C), enabling autoclaving (121°C, 15 psi) for sterilization.

Polycarbonate, though less chemically resistant than PP, offers superior optical clarity for applications requiring precise spectro-photometric analysis. A key limitation of plastic tubes is their lower tolerance to ultrahigh centrifugal forces compared to glass, restricting their use in high-speed ultracentrifugation.

Specialized designs address niche experimental demands:

Microcentrifuge tubes (0.2–2 mL capacity), often with snap caps, are optimized for small-volume samples in molecular biology (e.g., PCR, DNA purification).

Conical tubes (15–50 mL) feature tapered bottoms to concentrate pellets during cell culture or protein precipitation.

​Cryogenic tubes, constructed from reinforced PP or polyethyl sulfone (PES), endure temperatures as low as -196°C for long-term sample storage in liquid nitrogen.

​Sterile pre-filled tubes, such as Vacutainer® blood collection tubes, integrate additives (e.g., EDTA, heparin) or gel barriers for clinical diagnostics, ensuring sample integrity during centrifugation.

Selecting the appropriate tube type hinges on balancing chemical compatibility, thermal requirements, and mechanical durability.

For instance, PP tubes are preferred for routine cell pelleting, while glass tubes remain indispensable for solvent-heavy extractions. Specialty variants like filter-equipped tubes streamline workflows by combining separation and filtration steps, reducing contamination risks.

Centrifuge tubes are available in volumes ranging from ​0.5 mL microtubes to ​50 mL conical tubes and larger.

Smaller tubes (0.5–2 mL) are ideal for high-throughput applications such as PCR or enzymatic assays, while larger capacities (15–50 mL) accommodate cell culture suspensions or protein precipitations. Oversized tubes may compromise centrifugation efficiency due to inadequate rotor fit, whereas undersized tubes risk sample overflow.

Tube material and design must align with the centrifuge’s rotor specifications.

For example, ​fixed-angle rotors require tubes with reinforced walls to withstand lateral stress, whereas ​swing-bucket rotors demand uniform weight distribution to prevent imbalance.

The tube’s maximum rated ​relative centrifugal force (RCF) must exceed the instrument’s operational RCF; polypropylene tubes typically tolerate up to 30,000 × g, while polycarbonate may deform above 20,000 × g. Always verify manufacturer guidelines (e.g., Beckman Coulter, Eppendorf) for rotor-tube compatibility.

Applications involving extreme temperatures necessitate careful material selection.

For ​autoclaving (121°C) or high-temperature centrifugation, polypropylene or glass tubes are preferred due to their thermal stability.

Conversely, ​cryogenic storage (-80°C to -196°C) requires tubes made of polymers like polypropylene or fluorinated ethylene propylene (FEP) that resist embrittlement. Glass tubes are unsuitable for sub-zero applications due to fracture risks.

The tube material must resist degradation by solvents, acids, or bases present in the sample. Polypropylene excels in most biochemical applications, offering broad resistance to alcohols, dilute acids, and alkalis. For aggressive solvents like chloroform or dimethyl sulfoxide (DMSO), fluoropolymer tubes (e.g., PFA, FEP) are recommended. Polycarbonate, while optically clear, is incompatible with acetone or strong bases, limiting its utility in organic chemistry workflows.

Certifications ensure compliance with experimental or regulatory standards.

Sterile, DNase/RNase-free tubes are mandatory for molecular biology to prevent nucleic acid degradation or microbial contamination.

Clinical or pharmaceutical applications may require ​FDA-approved or ​ISO 13485-certified tubes, particularly for in vitro diagnostics or drug development. Pre-filled vacuum tubes (e.g., EDTA-coated blood collection tubes) must meet CLIA or CAP standards for diagnostic accuracy.

A holistic approach combines these factors. For instance, isolating RNA from whole blood demands a ​sterile, RNase-free 15 mL polypropylene tube rated for high RCF (≥10,000 × g) to pellet cells while retaining chemical resistance to lysing buffers. Similarly, ultracentrifugation of lipoproteins requires ​thick-walled polycarbonate tubes compatible with titanium rotors and rated for >100,000 × g.

Proper balancing is critical to prevent rotor imbalance, which can damage equipment, generate excessive noise, or even cause catastrophic failure.

Ensure that ​centrifuge tubes of equal volume and mass are placed symmetrically in opposing rotor slots. For odd-numbered samples, use a balance tube filled with water or a dummy load matching the sample’s density. Always verify that tube holders or adapters are compatible with the rotor type (e.g., fixed-angle vs. swing-bucket) to avoid misalignment.

Overfilling ​centrifuge tubes increases the risk of leakage, aerosol formation, or tube collapse under high centrifugal force.

Fill tubes to no more than ​75% of their rated capacity, especially when processing viscous liquids (e.g., blood, glycerol solutions).

Securely fasten caps or lids to prevent sample loss; for example, screw-thread caps require a firm twist until resistance is felt, while snap-fit lids must audibly click into place.

Inspect tubes for cracks or deformation before use, as compromised integrity can lead to catastrophic failure at high speeds.

Operating ​centrifuge tubes beyond their rated temperature or speed limits risks tube failure and sample loss. For high-temperature runs (e.g., heated centrifuges), ensure tubes are rated for at least ​10–15°C above the target temperature to account for frictional heating. Conversely, tubes used in cryocentrifuges must withstand sudden thermal shocks. Adhere strictly to the ​maximum relative centrifugal force (RCF) specified by the tube manufacturer—exceeding this limit can deform tubes or cause rotor instability. Polypropylene tubes, for instance, typically tolerate ≤30,000 × g, whereas ultracentrifugation requires specialized polycarbonate or titanium tubes.

When centrifuging biohazardous, radioactive, or corrosive materials, use ​sealed centrifuge tubes with leak-proof closures and secondary containment (e.g., sealed rotor buckets or biosafety cups).

For biohazards, choose tubes certified for Biosafety Level 2 (BSL-2) or higher, and decontaminate exteriors with 70% ethanol before loading.

Radioactive samples require tubes made of low-binding materials (e.g., polyethylene) to minimize adsorption. Always work in a fume hood or biosafety cabinet when volatile or airborne hazards are present.

Case Example: Centrifuging Biohazardous Blood Samples

Use ​RNase-free, leak-proof centrifuge tubes with screw caps.
Balance tubes in a sealed rotor bucket within a biosafety cabinet.
Centrifuge at 3,000 × g for 10 minutes to separate serum.
Decontaminate the rotor and tubes with 10% bleach solution post-run.

Regularly inspect ​centrifuge tubes for stress marks, discoloration, or warping, and replace them proactively. Document usage logs to track tube lifespan, particularly for reusable tubes subjected to autoclaving or chemical exposure. By prioritizing these practices, laboratories can ensure operational safety, prolong equipment longevity, and maintain reproducible results.

Yes, ​reusable centrifuge tubes made of durable materials like polypropylene or polycarbonate can be reused if they are thoroughly cleaned, sterilized, and inspected for damage (e.g., cracks, warping, or cap wear). However, disposable tubes, often marked as “single-use,” should never be reused due to risks of contamination or structural failure. Always check the manufacturer’s guidelines to confirm reuse compatibility.

Avoid overfilling: Fill tubes to ≤75% capacity, especially with viscous or volatile liquids.

​Secure closures: Ensure screw caps are tightened until resistance is felt, or snap caps audibly click into place.

Balance loads: Imbalanced rotors generate excessive force, increasing tube stress.

​Use compatible materials: Select tubes rated for the required speed (RCF) and temperature.

Screw-cap tubes: Provide a tighter seal, ideal for high-speed runs, hazardous samples, or long-term storage.

​Snap-cap tubes: Convenient for quick access but may leak under extreme RCF or temperature fluctuations.

Material compatibility: Screw caps often include silicone gaskets for enhanced sealing, while snap caps rely on friction fit.

Test tubes are general-purpose glass or plastic tubes for mixing or storage, not designed to withstand high centrifugal forces. ​Centrifuge tubes, however, are engineered with reinforced walls, conical bottoms for pellet formation, and secure closures to endure pressures up to 30,000 × g.

No. Only tubes labeled as “autoclavable” (typically polypropylene or PFA) can withstand steam sterilization (121°C, 15–20 psi). Tubes made of polyethylene or polystyrene may melt or deform. Always verify the manufacturer’s temperature tolerance.

Cleaning: Rinse tubes with distilled water immediately after use. For stubborn residues, soak in mild detergent or 70% ethanol. Avoid abrasive brushes.

​Sterilization: Autoclave autoclavable tubes at 121°C for 20 minutes. For chemical sterilization, soak in 10% bleach (sodium hypochlorite) or 70% ethanol for 30 minutes, then rinse thoroughly.

Proper maintenance and disposal of ​centrifuge tubes are essential for laboratory safety, regulatory compliance, and environmental responsibility. Make sure you follow these points if you want to make your centrifuge tubes reusable and make waste disposal ethical.

Thorough cleaning prevents cross-contamination and extends the lifespan of reusable ​centrifuge tubes.

Use ​autoclavable centrifuge tubes (typically polypropylene or PFA) and sterilize at ​121°C (15–20 psi) for 20 minutes.Allow tubes to cool gradually to avoid warping.
Note: Non-autoclavable materials like polystyrene will deform.

Soak tubes in ​70% ethanol or ​10% sodium hypochlorite (bleach) for 30 minutes.

Rinse thoroughly with distilled water to remove chemical residues.

For organic residues, use enzymatic cleaners (e.g., Tergazyme®).

​Safe Disposal Methods for Biohazardous Waste
Improper disposal of contaminated ​centrifuge tubes risks exposure to pathogens or toxins.

Autoclave biohazardous tubes before disposal.

For chemical/radioactive waste, neutralize or stabilize according to Safety Data Sheets (SDS).

Use ​red biohazard bags for autoclaved biological waste.

Place chemically contaminated tubes in leak-proof containers labeled with hazard symbols.

Sharps containers for broken glass tubes.

Follow OSHA 29 CFR 1910.1450 (hazardous chemical disposal).

Adhere to institutional protocols for radioactive waste (e.g., half-life-based storage).

Balancing laboratory efficiency with sustainability requires mindful choices.

​Recycling vs. Single-Use Plastics:

​Recyclable Tubes: Polypropylene tubes (marked ♻️5) can be recycled if uncontaminated.

​Single-Use Tubes: Reduce cross-contamination risks but contribute to plastic waste. Opt for brands with take-back programs (e.g., TerraCycle®).

​Reusable Tubes:
Lower environmental impact over time but require water/energy for cleaning.
Prioritize reusable options for non-hazardous, high-volume workflows.

Alternatives:
Biodegradable tubes (e.g., PLA-based) for low-speed applications.
Glass tubes for non-disposable needs, though energy-intensive to produce.

Case Example: Disposing of Ethidium Bromide-Contaminated Tubes
Deactivate ethidium bromide using activated carbon or commercial detoxification kits.
Place decontaminated tubes in rigid plastic containers labeled “Non-Hazardous Waste.”
Dispose via certified chemical waste contractors if detoxification is incomplete.

Selecting and using ​centrifuge tubes effectively is foundational to achieving reliable experimental results and maintaining laboratory safety.

​Prioritize Quality: Opt for tubes made from durable, chemically resistant materials (e.g., polypropylene) that match your speed (RCF) and temperature requirements.

​Ensure Compatibility: Verify tube compatibility with rotors, samples, and protocols—whether handling biohazards, extreme temperatures, or high-speed runs.

​Adhere to Safety Protocols: Follow balancing guidelines, avoid overfilling, and implement proper disposal practices to protect equipment and personnel.

For laboratories seeking ​high-performance centrifuge tubes, ​GenFollower offers a premium range designed to meet diverse experimental needs. Their tubes are:

Versatile: Available in multiple sizes (0.5 mL to 50 mL), and closure types (screw-cap, snap-cap).

​Certified: Manufactured under ISO 13485 standards, withstanding temperatures from -80°C to 121°C and RCF up to ​30,000 × g.

​User-Validated: Praised for leak-proof seals, clarity for pellet visualization, and compatibility with autoclaving or cryogenic storage.

Let us help you improve your experimental efficiency— explore ​GenFollower’s centrifuge tube collection today.