How is pipetting performed?

1. The volume

Commercially available glass pipettes generally have sample volumes ranging from 1 mL and 20 mL. While glass pipettes are very useful for sampling large volumes (V > 5 mL) and standard volumes (1 mL, 2 mL), they cannot ensure accuracy for "intermediate" volumes (1.7 mL) or volumes of less than 1 mL. In these cases, micropipettes should be preferred.

2. The room temperature

The nominal volume of the glass pipettes is indicated for sampling at 20°C. A variation of this temperature in summer (25 – 30°C) can lead to a significant change in this volume due to the expansion of the glass.

3. The cleaning

As with all precision glassware, it is impossible to clean a pipette at high temperature without the risk of disturbing the precise measurement of its volume. Therefore, glass pipettes CANNOT be cleaned in a dishwasher, nor can they be pyrolyzed (removal of all traces of organic material). It is also not recommended to leave them in the oven for too long.