Micropipettes are lab tools designed to handle very small volumes of liquid with very high levels of precision and accuracy, leading to reliable, repeatable results. In general, micropipettes transfers liquids down to volumes of 0.1 microliters (µL).
A micropipette uses the air displacement created by an internal piston to fill its tip with liquid and then dispense the liquid when the operator depresses its plunger, according to Pathways over Time, a microbiology resource hosted by Boston College. Micropipettes are commonly used in chemistry, biology, forensics, pharmaceuticals, biopharmaceuticals and drug discovery.
As delicate precision instruments, micropipettes should be stored carefully, following manufacturer recommendations and best practices.
Micropipette vs. Pipette vs. Pipettor: Terminology
Micropipettes are one type of pipette, and many manufacturers refer to them simply as “pipettes.” There are also simpler, nonmechanical pipettes used for different purposes in the lab, such as serological pipettes and transfer pipettes. The term “pipetter” is sometimes used for the mechanical tools as a way around this ambiguity.
The storage tips below are suitable for pipettes, micropipettes or pipetters that use air displacement driven by an internal piston.
The Consequences of Improper Pipette Storage
Here are some of the ways that poor storage practices can affect a pipette, as described by manufacturers and industry experts:
- Storing a pipette horizontally can make its piston more difficult to move, because piston lubricant can accumulate on one side, or the piston itself can drop, according to manufacturer CAPP.
- Storing a pipette with aspirated liquid inside the pipette tip can lead to corrosion or contamination that can have a significant effect on pipetting results, according to CAPP. Even laying a pipette on its side with fluid in the tip raises the possibility that fluid will reach the piston and cause contamination and corrosion, according to manufacturer Hamilton.
- Storing a pipette in a drawer or laying it on a workbench can easily lead to contamination of the instrument, according to manufacturer Gilson.
- Storing a pipette without first removing the tip can lead to cross-contamination, unintentional tip reuse and evaporation of trapped liquids into the inner workings of the instrument, according to the Laboratory People. a blog maintained by a testing equipment company based in the United Kingdom.
- Storing a pipette casually (not in an appropriate hanger) can lead to dropped instruments, which is one of the two main causes of damage to these tools, according to manufacturer Mettler Toledo.
Best Practices for Pipette Storage
- Store pipettes vertically (upright).
- Set pipettes to their highest volume setting, according to Promega Connections, a blog maintained by life sciences manufacturer Promega. This will lessen the stress on the instruments’ springs, according to the Laboratory People.
- To allow pipette operators to take fatigue breaks without setting down their instruments horizontally, use a stand, carousel or shelf mount, according to pipette calibration services provider TTE Laboratories.
- Remove pipette tips to avoid corrosion and contamination, according to CAPP, and to prevent cross-contamination and internal evaporation, according to Laboratory People.
Pipette Racks and Other Storage Options
There are several types of pipette storage, including pipette racks and stands, that can help you follow the storage recommendations above:
- A carousel-style stand can hold several pipettes vertically in a small amount of space.
- A pipette storage rack can also hold several pipettes in a non-horizontal orientation.
- Electronic pipettes are likely to require specialized charging stands.
- Wall-mounted holders allow pipettes to hang in an upright position. Some wall mounts have brackets for permanent installation, while others have strong magnets, allowing them to be placed wherever there is space on a ferrous wall.