Laboratory tubes: how can material, format and closure be matched to the sample?

From sample collection to analysis, the laboratory tube safeguards your samples: 0.5–2 mL microcentrifuge tubes for preparation, 15/50 mL conical tubes for centrifugation, glass tubes for chemistry and 5 mm NMR tubes for spectroscopy. The choice of material (PP, PS, glass), closure system (snap or screw cap), sterility, allowable RCF and solvent compatibility all influence result reliability. Clear, accurate graduations, RNase/DNase-free options, coding and batch traceability complete the picture, from the benchtop to cryogenic storage.

What are the different types of laboratory tubes?

Because a protocol is only as reliable as its container, there’s a tube for every task. Microcentrifuge tubes (0.5–2 mL) in PP withstand high RCF (up to ~20,000 g depending on model) and -80 °C / 121 °C freeze–autoclave cycles. Hinged caps for day-to-day work; screw caps with O-ring for a leak-tight seal and sensitive samples.

Plastic tubes include conical 15/50 mL in PP for centrifugation (up to 12,000–20,000 g depending on reference), ultra-clear PS 12×75 mm for flow cytometry/diagnostics, or PET for collection and storage. PP is autoclavable; PS offers optical clarity but is not compatible with high RCF or autoclaving.

Borosilicate glass tubes (12×75, 13×100 mm, etc.) resist solvents and moderate thermal shock, and can be reused after washing. Ideal for chemistry and reactions requiring chemical inertness.

NMR tubes (typically 5 mm Ø, ~178 mm) in high-purity glass or quartz ensure concentricity and straightness for optimal field homogeneity. Perfect for ~0.5 mL volumes, with matching caps and spinner.

Tube strips (PCR strips 8/12×0.2 mL) with thin walls accelerate heat transfer; flat or optical caps for qPCR. Choose by volume, material, closure, transparency, sterility, RCF, temperature range and chemical compatibility. See the comparison table below.

Type	Material	Applications / advantages
Microcentrifuge tube 1.5–2 mL	PP	DNA/RNA prep, high RCF centrifugation, autoclavable, low-binding variants
Conical tube 15/50 mL	PP	Culture, gradients, pellets; high RCF resistance, easy-to-read graduations
Tube 12×75 mm	PS	Flow cytometry/diagnostics; optical clarity, cold use, not autoclavable
Glass tube	Borosilicate 3.3	Chemistry, heating, aggressive solvents; reusable, chemically inert
NMR tube 5 mm	Glass/quartz	High-resolution NMR; precise geometry, low background, dedicated caps
PCR strip 8/12×0.2 mL	Optical PP	PCR/qPCR; thin-walled, optical caps, compatible with 96-well cyclers

Which fields use laboratory tubes?

• Life sciences : nucleic acid extraction, enzyme preparation, cell culture, PCR/qPCR and short-term storage.
• Pharmaceutical & cosmetics : quality control, stability studies, sterile sampling, method validation.
• Food & beverage : microbiological testing, allergens, enzymatic assays, field sampling.
• Environment : water/soil, metals, turbidity; aliquoting and cold storage.
• Chemistry : reactivity tests, solubility, kinetic monitoring, NMR for structural elucidation.
• Control & diagnostics : flow cytometry (PS 12×75), haematology, cryo-compatible PP biobanking.

The different types of laboratory tubes available

Frequently asked questions about laboratory tubes

How do I choose the material for a tube?
PP for centrifugation/autoclaving, PS for optical clarity and flow cytometry, PET for sample collection, borosilicate glass/quartz for aggressive solvents and NMR.

Snap cap or screw cap: which should I choose?
Snap cap for quick handling; screw cap with a seal/O-ring for leak-tightness, vigorous mixing, transport and sensitive samples.

Up to what RCF can microtubes be spun?
Depending on the model, often 17,000–20,000 g. Check the manufacturer’s limit and rotor/tube compatibility to avoid deformation and leaks.

Are PS tubes autoclavable?
No. Polystyrene deforms with heat. For autoclaving, choose PP (or glass) and follow the cycle parameters.

What format is a standard NMR tube?
5 mm outer diameter and ~178 mm long. For high fields, opt for high-concentricity, thin-walled tubes.

Can you freeze at -80 °C in a conical tube?
Yes, in suitable PP with a screw cap; leave headspace for expansion and use racks to prevent cracking. Always follow the manufacturer’s recommendations.

How can I minimise RNase/DNase contamination?
Use tubes certified RNase/DNase-free, clean gloves, filtered tips; avoid prolonged skin contact and change batch if in doubt.