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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.
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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 0.1l and 25mL BUT… • Typically used for 0.1L-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
“Pipetman” • Rainin brand - now they call it “classic”, but they are extremely common!
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
Dual-Dye, Dual-Wavelength, Ratiometric Photometry Artel 2007
Maximum Permissible Errors Gilson