Types of Micropipette: Which One Your Lab Actually Needs
Updated: 3 days ago
The two main types of micropipette are air displacement and positive displacement. Air displacement micropipettes move liquid with a cushion of air and suit most water-based work. Positive displacement micropipettes have a piston that touches the liquid, so they stay accurate with viscous, volatile or dense liquids.
Both come as fixed or variable volume, single or multichannel, and manual or electronic. Most labs need variable-volume air displacement micropipettes in P20, P200 and P1000.
Type | Pros | Cons | Use it when |
|---|---|---|---|
Air displacement | Cheap standard tips. Very accurate with water-like liquids. Easy to service. | Loses accuracy with viscous, volatile or dense liquids. | Buffers, media, most routine work. |
Positive displacement | Accurate with any liquid. No aerosol carry-over. | Special capillary tips cost more. | Glycerol, oils, solvents, whole blood. |
Fixed volume | Most accurate and robust. No setting mistakes. | One volume only. | You repeat one volume all day (QC, kits). |
Variable volume | One pipette covers a 10× range. | Setting errors. Less accurate at the bottom of the range. | Research, teaching, changing methods. |
Multichannel (8 or 12) | Fills a plate column in one stroke. | Heavier. Tips must seal evenly. | ELISA, PCR plates, serial dilutions. |
Electronic | Less hand strain. Programmable. | Costs more. Needs charging. | Hundreds of samples a day. |
The short version
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The two main types of micropipette
Air displacement micropipettes suit water-based samples; positive displacement micropipettes suit viscous, volatile or dense liquids. The difference is whether a cushion of air sits between the piston and the liquid.
1. Air displacement micropipettes
Air displacement micropipettes are the standard choice for water-based samples: a piston pushes a cushion of air, and the air moves the liquid in the tip.
Pros: standard tips are cheap and easy to find; accurate and precise with aqueous samples; simple to calibrate and service.
Cons: the air cushion expands and contracts, so viscous, volatile, dense or warm liquids give wrong volumes.
Use it for: buffers, reagents, culture media, DNA and protein solutions, most QC work.
2. Positive displacement micropipettes
Positive displacement micropipettes are the choice for viscous, volatile or dense liquids: the piston sits inside the tip and touches the liquid directly, like a tiny syringe.
Pros: accurate with any liquid; no aerosols, so no cross-contamination between samples.
Cons: needs special capillary-piston tips that cost more per sample.
Use it for: glycerol, oils, detergents, organic solvents, whole blood, and PCR work where contamination is a risk.
“ If you only pipette viscous liquids now and then, you don't need a second pipette. Reverse pipetting with your air displacement pipette gets you most of the way. — LS Scientific |
Fixed vs variable volume micropipettes
Fixed-volume micropipettes dispense one set volume and are the most accurate; variable-volume micropipettes adjust across a range (usually 10×) and suit labs whose volumes change.
Fixed volume
Choose a fixed-volume micropipette when you dispense the same volume all day; it is set at the factory to one volume, such as 100 µl or 1000 µl.
Pros: the most accurate option; nothing to set, so no setting mistakes; fewer moving parts.
Cons: you need one pipette per volume.
Use it when: a test uses the same volume every time, such as a QC method or a diagnostic kit.
See the IKA PETTE fix range, available from 5 µl to 1000 µl.
Variable volume (adjustable)
Choose a variable-volume micropipette when your volumes change; you dial in the volume across about a 10× range, such as 20–200 µl.
Pros: one pipette does many jobs; the best value for most labs.
Cons: it's easy to set the wrong volume; accuracy drops in the bottom 10% of the range.
Use it when: your volumes change from method to method.
Our most popular is the IKA PETTE vario 100–1000 µl.
Single-channel vs multichannel micropipettes
A single-channel micropipette handles one sample at a time; a multichannel (8 or 12 tips) fills a whole row of a 96-well plate in one stroke. Buy a multichannel only if you work with plates.
Single-channel: one tip, one sample. Right for tubes, vials and most bench work.
Multichannel (8 or 12 tips): fills a whole row or column of a 96-well plate in one stroke. It cuts the number of strokes by up to 90%, but is heavier and needs every tip to seal evenly.
If you run ELISA, PCR plates or microbiology plates every week, a multichannel pays for itself in time. See the IKA PETTE multi 8-channel and 12-channel.
Manual vs electronic micropipettes
Manual micropipettes suit most labs; electronic micropipettes are worth it only for high-throughput or repetitive dispensing.
Manual: no battery, no charging, lower cost, easy to repair. Right for most labs.
Electronic: a motor drives the piston, so every stroke is the same speed. Less hand strain, and it can repeat-dispense. Worth it only if one person pipettes hundreds of samples a day.
The four sizes of micropipette (and what each is for)
The four standard micropipette sizes are P2 (0.1–2 µl), P20 (2–20 µl), P200 (20–200 µl) and P1000 (100–1000 µl). The number is the maximum volume in microlitres. Most labs also add a P10.
Size | Range | Typical uses | Our model |
|---|---|---|---|
P2 | 0.1–2 µl | Enzymes, DNA sequencing | |
P10 | 0.5–10 µl | PCR primers, gel loading | |
P20 | 2–20 µl | PCR mixes, small samples | |
P100 | 10–100 µl | Standards, small reagent volumes | |
P200 | 20–200 µl | Buffers, ELISA, plating | |
P1000 | 100–1000 µl | Media, reagents, extractions | |
P5000 / P10 ml | 0.5–5 ml / 1–10 ml | Media prep, dilutions |
Rule of thumb Pick the smallest pipette that holds your volume. A P1000 set to 100 µl is much less accurate than a P200 set to 100 µl. Stay above about 35% of the pipette's maximum where you can. |
Sizes most labs need | 3 |
Best accuracy zone | 35–100% |
Check calibration every | 3–12 months |
Which micropipette is best for your lab?
For most labs, the best micropipette is a variable-volume air displacement set in P20, P200 and P1000, from a brand you can get calibrated locally. Specialist work changes the answer:
Starting from scratch: a kit of three variable pipettes with tips. The IKA PETTE Classic Kit covers most bench work, the MicroKit covers small volumes, and the MacroKit covers millilitre work.
Molecular biology and PCR: P2, P10 and P20, plus filter tips.
Microbiology and clinical: P200 and P1000, plus a multichannel for plates.
QC with fixed methods: fixed-volume pipettes at the volumes your SOPs use.
Teaching labs: robust variable pipettes that can be autoclaved and serviced.
“ The cheapest micropipette is the one that stays accurate. A pipette that drifts costs you repeat tests, wasted reagents and results you can't defend in an audit. — LS Scientific |
In hot or humid labs this matters even more. Let pipettes, tips and liquids reach room temperature before you work, and have every pipette checked on a schedule.
Pipette vs micropipette: what's the difference?
A pipette measures millilitres using a glass or plastic tube and a pipette filler; a micropipette measures microlitres using a piston and disposable tips.
Pipette | Micropipette | |
|---|---|---|
Volume | Millilitres (1–100 ml) | Microlitres (0.1–1000 µl), up to 10 ml |
How it works | Glass or plastic tube with a pipette filler | Piston with a disposable tip |
Accuracy | Good for ml volumes | High at µl volumes |
Typical use | Titrations, volumetric prep | Molecular biology, clinical, QC |
Working with glass pipettes? See how to use a pipette filler, and which to buy.
Keep them accurate: calibration and care
Calibrate micropipettes every 3–12 months to ISO 8655, and use good technique between checks.
Calibrate every 3–12 months to ISO 8655, more often for heavy use or regulated work.
Pre-wet the tip two or three times before you take your sample.
Hold it upright when you aspirate and at an angle against the wall when you dispense.
Use tips that fit. A poor seal is the most common cause of wrong volumes.
Never lay a pipette down with liquid in the tip. Liquid runs into the piston and damages it.
Store it upright on a stand, set to its maximum volume.
Frequently asked questions
What are the two main types of micropipettes?
Air displacement and positive displacement. Air displacement micropipettes move liquid with a cushion of air and suit most water-based work. Positive displacement micropipettes have a piston that touches the liquid, so they stay accurate with viscous, volatile or dense liquids.
What are the four sizes of micropipettes?
The four standard sizes are P2 (0.1–2 µl), P20 (2–20 µl), P200 (20–200 µl) and P1000 (100–1000 µl). The number is the maximum volume in microlitres. Most labs add a P10 for PCR and gel loading.
What is a P10 micropipette?
A P10 is a micropipette with a maximum volume of 10 µl, usually adjustable from about 0.5 to 10 µl. It is used for PCR primers, enzymes, DNA samples and loading gels.
Which micropipette is best?
For most labs, the best choice is a set of variable-volume air displacement micropipettes in P20, P200 and P1000 sizes, from a brand you can get calibrated and serviced locally. Add a multichannel if you work with 96-well plates.
What is a micropipette used for?
A micropipette measures and transfers small volumes of liquid, from 0.1 µl to 10 ml, accurately and repeatably. It is used in molecular biology, microbiology, clinical, pharmaceutical and food testing labs.
How much is 1 ml in a micropipette?
1 ml is 1000 µl. Set a P1000 micropipette to 1000 to transfer 1 ml.
What is the difference between a pipette and a micropipette?
A pipette usually means a glass or plastic tube used with a pipette filler to measure millilitres. A micropipette is a precision instrument with a piston and disposable tips that measures microlitres.
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