Air Displacement Pipette

Zeus is equipped with anti droplet control adc.

Air displacement pipette.

When using positive displacement pipettes there is no elastic air space to expand or contract so the aspiration force remains constant unaffected by the physical properties of the sample. These pipettes operate by piston driven air displacement. These liquids tend to vaporize in the tip which raises the air pressure resulting in liquid dripping from the tip. Due to its high accuracy this laboratory tool is commonly used in standard pipetting applications.

In an air displacement pipette an air cushion separates the liquid in the plastic tip from the piston inside the pipette. In positive displacement pipetting the piston is in direct contact with the liquid. Adjust pipette to liquid becomes fixed volume pipette for adjusted volume. No air cushion therefore no problem.

However conditions such as temperature atmospheric pressure as well as the specific gravity and viscosity of the solution may have an effect on the performance of air displacement pipettes. Getting down to the basics an air displacement pipette is a common laboratory tool used to handle a measured volume of liquid between 1 µl to 1000 µl 1 ml. A vacuum is generated by the vertical travel of a metal or ceramic piston within an airtight sleeve. Volatile liquids like acetone and methanol can be extremely difficult to pipette using air displacement.

Unlike an air displacement pipette which dispenses liquid using an air cushion in the pipette tip the piston in a positive displacement pipette makes direct contact with the sample allowing the aspiration force to remain constant. The liquid s density influences the size of air cushion e g. Too low too high volume is pipetted. As with any gas the air cushion varies according to the characteristics of liquids as well as in part by lab or.

As the piston moves upward driven by the depression of the plunger a vacuum is created in the space left vacant by the piston. Positive displacement pipettes are a type of pipette that operates via piston driven displacement. Laboratory pipettes can function either via air displacement or by positive displacement principles. Acids bases and solvents are the worst enemies of any air displacement pipette.

Both pipette types have a piston that moves in a cylinder or capillary.