Pipettes - How it works

In recent years, the market for liquid handling has grown rapidly, due to the rapid development of biotechnology and molecular biology. In these fields, processes for dispensing very small quantities of liquid in the microliter and milliliter range play a very important role. This is a constant and indispensable component of many experimental methods.

Common analytical methods in biology and the chemical industry require highly precise liquid handling processes. At the same time, new techniques such as genetic engineering are placing increasing demands on the design, construction and materials of these systems.

One of the most common activities of laboratory operators is to sample or add reagent during tests. A pipette is used to correctly measure a specified quantity of liquid. The risks associated with handling liquids are well known, but there are still other physical hazards for laboratory operators. They run thousands of tests every day, with problems associated with the plunger's continual depression while pipetting, in turn causing pipetting errors. Many factors linked to pipetting, tips and laboratory operators affect pipetting accuracy and repeatability.

Sampling (pipetting), i.e. the measurement and transfer of liquid volumes in the milliliter and microliter range, has become the most frequent operation in scientific and medical laboratories. Rapid, accurate execution of this operation is a prerequisite for success. Most of these operations are carried out using modern air column pipettes. The many advantages of these devices make them ideal for the efficient dosing of small quantities of liquid. The use of top-quality air column pipettes makes for highly productive, time-saving work.

The aim of articles [P 1 330] and is to present the practical and theoretical aspects of pipetting with air column pipettes.