LimsPulse
Volumetric & glassware

Micropipette (Piston-Operated Pipette)

A hand-held, piston-operated device that measures and dispenses small liquid volumes, typically 0.1 µL to 10 mL, using disposable tips. Used for standards, dilutions, microbiology and bioassays.

  • Pharmaceutical
  • Biotech
  • Clinical diagnostics
  • Universities
  • Food & beverage
Photo of a Micropipette (Piston-Operated Pipette)
Photo: Microrao, CC BY-SA 4.0 (cropped), via Wikimedia Commons
LEARN & PRACTICE

Test your Micropipette knowledge

Multiple-choice questions

Pick an answer to see whether you are right and why.

  1. Q1. Which standard describes the gravimetric calibration of piston pipettes?

    basic

  2. Q2. What does the systematic error of a pipette describe?

    basic

  3. Q3. The mean mass of ten 1000 µL deliveries is 0.99448 g and Z = 1.0033 mL/g. What is the mean volume?

    intermediate

  4. Q4. Why is the Z factor slightly greater than 1 mL/g?

    intermediate

  5. Q5. Which technique is best for viscous or foaming liquids with an air-displacement pipette?

    basic

  6. Q6. Why are tips pre-wetted before gravimetric testing?

    intermediate

Viva questions

Think of your answer first, then open it to compare.

  1. 1. Describe how you would check a 1000 µL pipette gravimetrically.

    Equilibrate pipette, tips and water in the test room. Pre-wet the tip, dispense ten deliveries of water into a tared vessel on a calibrated balance, record masses and water temperature, convert each mass to volume with the Z factor, then calculate mean, systematic error and CV and compare with ISO 8655-2 or SOP limits.

  2. 2. Why might the same pipette pass with one analyst and fail with another?

    Pipetting results depend on technique: immersion depth, angle, plunger speed, pre-wetting, hand warming and tip fit. That is why training and consistent technique matter as much as calibration.

  3. 3. When would you use a positive-displacement pipette?

    For viscous, dense or volatile liquids (for example glycerol, oils or organic solvents), where an air cushion would expand, contract or leave liquid behind. The piston touches the liquid directly, so these effects are avoided.

In LimsPulse · Calibration Management

Keep every Micropipette in control: usage logs, calibration and maintenance schedules, and automatic blocking of overdue instruments.

See how