Centrifuge Tube, Glass

Quick Answer: The Centrifuge Tube, Glass is a thick-walled glass tube that holds liquid samples while they are spun in a centrifuge. A glass centrifuge tube is chosen when the sample contains solvents that attack plastic or when tubes are to be washed and reused.

When to Choose Glass for Centrifugation

In a centrifuge, denser particles are driven to the bottom of the tube, forming a pellet, while the lighter liquid above, the supernatant, can be poured or pipetted off. Glass tubes are chosen over plastic for work with organic solvents such as chloroform, phenol, acetone and ether, which soften or dissolve many plastics. They can be washed, dried and sterilised repeatedly, and liquid levels and pellets are easy to see through the clear wall.

Glass has limits. It tolerates much lower centrifugal force than many plastic tubes, so it belongs in bench and clinical centrifuges at moderate speeds rather than high-speed rotors, and each tube’s rating should be known before use. Rubber cushions in the buckets help to spread the load. Tubes must be balanced in opposite positions, and any tube with a chip or crack should be discarded, because it can shatter under load.

Tubes of this kind are commonly made with a conical bottom that gathers a small pellet in the tip, graduated or plain; the listing does not state the bottom shape, graduation or capacity. A graduated glass centrifuge tube is listed separately for volume readings.

Specifications

Applications

• Preparing urine sediment for microscopy in a laboratory centrifuge during clinical pathology practicals
• Separating precipitates from solutions in chemistry and biochemistry
• Phenol-chloroform extraction and other solvent work in molecular biology
• Harvesting cells or microbes from broth cultures

Safe Centrifugation

• Inspect each glass centrifuge tube against the light for chips, scratches and star cracks before every run.
• Load tubes in opposite positions with equal volumes, and use cushions or adapters that fit the tube.
• Stay within the tube’s rated speed and let the rotor stop on its own before opening the lid.
• If a tube breaks, switch off, wait for the rotor to stop and clean the bucket with care, disinfecting it if the sample was biological.

Why Choose LabEquip

Clinical pathology labs, biochemistry teaching labs and chemistry departments keep glass centrifuge tubes for solvent work and for tests where tubes are reused. LabEquip lists them in Biology Lab Products; tell us the capacity and bottom shape you need through the contact page.

Frequently Asked Questions

When should I use glass instead of plastic tubes?

Use glass for organic solvents such as chloroform, phenol or ether that attack many plastics, and when tubes are to be washed and reused. Use plastic for high-speed runs.

How fast can a glass tube be spun?

Glass withstands much less centrifugal force than most plastic tubes, so it is used at moderate speeds in bench centrifuges. Know the tube’s rating and your rotor’s limits before each run.

Why are centrifuge tubes balanced?

An unbalanced rotor vibrates heavily, which can damage the centrifuge and break tubes. Tubes of equal mass must be placed directly opposite each other.

What is the conical bottom for?

A conical tip collects the pellet into a small area, making it easy to see and to remove the supernatant without disturbing it.

How should the tubes be cleaned?

Rinse promptly, soak in laboratory detergent, scrub gently with a soft tube brush so the inside is not scratched, rinse with distilled water and dry. Scratches weaken the glass under load.

What capacity and bottom shape do these tubes have?

Glass centrifuge tubes are made in several capacities, with conical or round bottoms and with or without graduations. The listing does not specify these, so confirm them when you enquire.

Last Updated: September 2026