Brush, Pipette

Quick Answer: The Brush, Pipette is a very long, slim laboratory brush with a narrow bristle head on a thin wire stem, used to scrub inside the bore of glass pipettes. A pipette brush reaches along the stem of graduated pipettes and into the upper stem of volumetric (bulb) pipettes, where films affect the volume delivered.

Fitting a Brush to a Pipette

Pipettes deliver volumes by drainage, so, like burettes, they depend on a clean wall. A graduated pipette has a uniform bore along its scale, and a long slim brush can pass through much of it from the top. A volumetric pipette has a narrow stem above and below a central bulb; the brush cleans the upper stem, but the bulb and the delivery tip are normally cleaned by soaking and drawing cleaning solution through. Nylon is a common bristle material for pipette brushes, as it resists detergents and does not rot; the material, length and diameter of this brush are not stated in the listing.

Brush diameter matters more for pipettes than for any other glassware. The head must be slightly larger than the bore so that the bristles touch the wall, but not so large that it jams; a jammed brush in a thin pipette is a common cause of broken glass and cut hands. Pipettes in a department range from small graduated sizes to large volumetric ones, so more than one brush size is usually needed. Compare the fibre pipette brush, which has a different head, and keep cleaned pipettes on a vertical pipette stand to drain.

Specifications

Using the Brush Safely

• Soak pipettes in a detergent bath or pipette jar first; brushing is for residues that soaking leaves behind.
• Hold the pipette near the end the brush enters, never at the far end, so the glass is not levered.
• Stop if the brush meets resistance; withdraw it and choose a smaller size.
• Rinse the pipette with tap water, then distilled water, and let it drain upright or on a stand.

Applications

• Cleaning graduated pipettes whose scale readings are affected by wall films.
• Scrubbing the upper stems of volumetric pipettes before accurate analytical work.
• Cleaning glass tubes and dropper pipettes of similar bore.
• Cleaning pipettes that have held protein solutions, oils or suspensions.

Why Choose LabEquip

Pipette brushes are ordered by analytical, pharmaceutical and teaching labs that clean their own volumetric glassware. LabEquip lists this brush in the General Lab Products range; send the pipette sizes you use through the contact page.

Frequently Asked Questions

Can this brush clean the bulb of a volumetric pipette?

Not fully. The brush cleans the upper stem, but it cannot work usefully through the narrow constriction into the bulb. The bulb and tip are cleaned by soaking in detergent and drawing the solution through with a pipette filler.

What brush diameter do I need for my pipettes?

The bristle head should be slightly wider than the pipette bore so it touches the wall, but it should slide in without force. Departments with several pipette sizes usually keep two or three brush diameters.

Why must pipettes be completely clean?

A pipette delivers its stated volume by draining under gravity. Grease or residue on the wall holds back liquid as droplets, so less is delivered than intended and results are wrong.

Is it safe to push the brush through the whole pipette?

Only through a uniform bore wide enough for the brush. Never force it through the tip or a constriction; a jammed brush can snap the pipette and cause a deep cut.

Where should pipettes be left to dry after cleaning?

Stand them tip down on a pipette stand or rack at room temperature so water drains away from the bore. Calibrated pipettes are not normally dried in a hot oven.

Should I use a pipette filler during cleaning?

Yes. Never use mouth suction, even for detergent. A pipette filler or bulb draws cleaning solution and rinse water through the pipette safely.

Last Updated: September 2026