Pipetting accuracy is the ability of a pipette to deliver the volume specified on the volume setting. In other words, the trueness of a measurement to the true value depends on the interplay of the elements in the system. Pipetting precision is the ability of a pipette to consistently deliver same-sized volumes of liquid over multiple aliquots. A pipette can be precise with regard to dispensing the same volume time after time, yet inaccurate because it fails to dispense the correct volume. An accurate and precise pipette dispenses volumes at the intended volume with each dispense. The pipette, the pipette tip, and the person operating the pipette form a 3-part system. The pipette operator, the person using the pipette to conduct research, has a high degree of influence on the accuracy of results. As such, it is important that operators are trained to use a pipette. There are some powerful, yet simple techniques that can greatly improve pipetting accuracy. The
Rainin Pipetting Technique poster offers a good summary. Additionally, Rainin offers the
Good Pipetting Practice online seminar to assist in learning the proper way to pipette.