Pipette, Pasteur, Disposable

Quick Answer: A disposable Pasteur pipette is a simple dropping pipette with a long, narrow tip, used once for transferring small volumes of liquid and then discarded. Used with a rubber teat, it moves drops and small portions of liquid between containers without cross-contamination.

A Dropper Meant for One Job

The Pasteur pipette, named after Louis Pasteur, is the everyday transfer tool of chemistry and biology benches. It carries no graduations for accurate measurement; its purpose is to move liquid, a drop at a time or a few cubic centimetres at once, from one vessel to another. Disposable versions are used once and thrown away, which removes the risk of carrying one sample or reagent into the next and saves washing narrow tips that are hard to clean.

Two forms are sold under this name: glass pipettes with a long capillary tip, used with a separate rubber teat, and one-piece plastic transfer pipettes with an integral bulb. The listing does not specify which is supplied, or the length. Glass tips resist organic solvents and tolerate warm liquids, while plastic ones do not break into sharp fragments.

Beyond simple transfers, the glass type is a tool of small-scale organic work. A plug of cotton wool pushed into the neck turns it into a filter pipette, and a short column of silica or drying agent packed in the same way gives a micro-column for small separations.

Applications

• Adding reagents dropwise in qualitative analysis and test-tube reactions
• Drawing off the liquid above a precipitate after centrifugation or settling
• Filtering small volumes through a cotton-wool plug in microscale organic chemistry
• Transferring samples in biology and microbiology practicals where cross-contamination must be avoided

Specifications

Care & Handling

• Keep the teat above the tip whenever the pipette holds liquid, so liquid does not run back into the teat and contaminate it.
• Use a fresh pipette for each reagent or sample; reusing one defeats the purpose of a disposable.
• Store unopened packs dry and flat so the fine tips are not crushed.
• Put used glass pipettes in a rigid broken-glass container, kept apart from paper and plastic waste.

Why Choose LabEquip

Laboratories that handle many samples, from school qualitative analysis to microbiology, get through Pasteur pipettes by the box. LabEquip lists them with the graduated pipette for measured volumes in its chemistry lab equipment range; send quantities through the LabEquip contact page.

Frequently Asked Questions

Can a disposable Pasteur pipette measure volumes accurately?

No. It is designed for transferring liquid, not measuring it. For approximate amounts you can count drops, but a graduated or bulb pipette is needed when the volume matters.

Why use disposable pipettes instead of washing droppers?

Each pipette touches only one liquid, so no trace of a previous reagent or sample is carried over. Narrow tips are also hard to clean thoroughly, and washing them takes time.

How do I make a filter pipette?

Push a small plug of cotton wool into the neck of a glass Pasteur pipette with a thin rod, clamp it upright and pour the solution through. It removes fine solids from a few cubic centimetres of liquid, which is useful in microscale work.

Are glass Pasteur pipettes safe for organic solvents?

Yes, glass resists common solvents such as propanone, ethanol and hexane. Plastic transfer pipettes may soften or dissolve in some solvents, so check before using them.

How should used glass pipettes be discarded?

Place them in a rigid, clearly labelled broken-glass or sharps container, never in general waste. If they held hazardous or biological material, they must be decontaminated or handled as hazardous waste under laboratory rules.

Why does liquid drip from the tip while I move the pipette?

Warmth from the hand expands the air in the teat, and volatile liquids evaporate into it, pushing liquid out. Hold the teat lightly, move quickly and keep the tip over the vessel.

Last Updated: September 2026