For easy and accurate handling, the micropipettes are attached transversely to a strong polyester backing tape to provide a continuous-feed bandolier. The backing tape is driven by sprocket holes in the same way that photographic film is handled. This enables continuous and exact delivery of the pipettes to the robotic actuator, thereby ensuring positional accuracy.

Each micropipette has a carefully controlled bore (0.4mm) engineered to tight geometric tolerances. The micropipettes are made of high grade polythene with a stainless steel piston, which gives them the ability to pierce most plate sealing films.

The positive displacement of liquid afforded by the micropipette piston means mosquito® can aspirate and dispense volumes down to 50nL with reproducible accuracy (CVs of 8% at 50nL), even when dispensing into a dry well. Changes in viscosity do not affect this accuracy.

When in use, the micropipettes come off the spool and pass through the dispensing head, where they are presented vertically over the plate [1]. The head then clamps the micropipette pistons and a programmable stepper motor moves the pistons to aspirate [2] and dispense [3]  the precise volumes required.