Use and Maintenance of Air Displacement Micropipettors * Modified from Bob O’Brien New Hampshire Community Technical College And J. Pino CCRI

Volumes Range : Micropipettors are made for measuring 0.1  l and 25mL BUT… Typically used for 0.1  L-1mL

Fixed Volume vs. Adjustable Volume Adjustable volume pipettors can be set to a desired volume but only work within a certain range. Often they are color coded, or bear special names. (eg. “P20” or “L200”) KNOW WHAT KIND YOU ARE USING AND USE THE RIGHT ONE! Each fixed volume pipettor can only be used to dispense a particular volume

Eppendorf Brand micropipette

FinnPipette Brand Micropipette

“Pipetman” Rainin brand - now they call it “classic”, but they are extremely common!

Digital Volume Adjustment

Multichannel Pipette

Pipet Tips Not all tips are created equal! Be sure to use the correct size Be sure to use the correct brand. Some pipets are very “picky”. If you use the wrong tip, it may not seal well and could affect the accuracy and precision of your measurements.

Tip sizes vary Learn to estimate/judge volume by appearance in a given size tip. It will help you catch mistakes.

Filter tips If you need to keep out contamination. Expensive so, use only when appropriate. Ex of use: in PCR

Defining Precision and Accuracy Pipette liquid delivery 2006Thermo Electron Corporation, Pipette guide

Important Definitions Calibration: The operations which assure that an instrument readings are accurate referenced to known standards. Validation: Proving that a system (equipment, procedure, process, material) will yield expected results. Test Equipment: Devices used during the calibration of instruments. These devices must be traceable to known standards.

Training and Documentation Ensure that all personnel involved with calibration are properly trained Training records must be maintained Documentation standards must be followed Version/Revision control assures only current documents are deployed

Auditing Periodic audits verify that the calibration plan is being followed Provides an opportunity to implement corrective action Formal audit report documents audit process

Example Operation SOP (10)

Example Operation SOP (12)

Example Calibration Work Form

Inspection of Pipette

Pipette calibration sop (4)

Dual-Dye, Dual-Wavelength, Ratiometric Photometry Artel 2007

Maximum Permissible Errors Gilson Maximum Permissible Errors GilsonISO865 ModelVolume (ul) Systematic error (ul) Random error (ul) Systematic error (ul) Random error (ul) P2000Min Max P1000Min Max