Pour de nombreuses applications, comme la distribution de solutions tampons ou de milieux de culture cellulaire, un distributeur en vrac peut constituer une bonne option. Une méthode d'obtention de gouttelettes de l'ordre du microlitre consiste à utiliser des électrodistributeurs à commutation rapide. Pour que le liquide puisse être distribué, ces distributeurs peuvent être alimentés par une conduite de liquide, par exemple depuis un réservoir sous pression. Une représentation schématique de ce système simple figure ci-dessous :
Pipetting, on the other hand, can be seen as a more sophisticated method of liquid handling. In its simplest form, this type of liquid transfer device removes a volume of liquid from a container by suction after which it is positioned over a target location where it will dispense the liquid. The sample liquid is usually held in a structure called a "tip". The tips may be stationary, such as thin tubes or large metal or plastic hypodermic needles, or disposable conical pieces, also known as disposable tips. The use of disposable tips can eliminate the risk of carry-over while reducing the dead volume when handling valuable reagents compared to dosing large volumes. Many systems are equipped with multiple tips, which can speed up the transfer of liquids by simultaneously drawing in from or dispensing into multiple containers. As a rule, each work peak in a system is called a channel.
Right now, the majority of automated liquid handling systems work with volumes in the microlitre to millilitre range. A current trend that can be observed is the increasing miniaturisation of assays; this enables laboratories to reduce reagent and sample costs while increasing throughput. An intelligent combination of pipetting and bulk dispensing can help optimise the automation of liquid handling processes.