Compressed air is not required—instead, these electrically operated positive displacement units use stepper motors and patented technology to advance and retract a piston inside the syringe barrel.
The operator uses a menu-driven touch pad to set deposit volume (as small as 0.1 microliter), flow rate and other specific criteria. After initial setup, there is no need to recalibrate or reset the positive displacement fluid dispenser due to changes in fluid viscosity or reservoir volume.