The Proper Pipetting Practices
Here are some of the techniques you can use to improve your pipetting skills!
|Improve accuracy up to 1% with good dispensing technique, touch the tube wall with the tip to dispense any remaining sample, then slide it up the wall to prevent liquid from clinging to the orifice.|
|Consistent pipetting rhythm and speed will improve accuracy by up to 5%, too fast or “jerky” aspiration can cause splashing, aerosols shaft contamination and loss of sample volume.|
|Pre-rinsing can increase accuracy by up to 0.2%. It helps neutralize capilary effects in pipettes and for large-volume tip, equalizes the air temperature inside the tip with the temperature of the sample.|
|Immerse the tip to the correct depth improves accuracy by up to 5%. Immersing the tip too deep can cause too much liquid to be aspirated. Positioning the tip too close to the liquid surface can aspirate air. Both results in inaccurate volume.|
| Hand temperature
When pipetting over long periods, heat from your
hand can cause air inside the pipette to expand and produce inaccurate results. Avoid it by placing the pipette on it’s stand between each pipetting cycle.
An ideal temperature for pipetting is 21.5 °C. Your
instrument and samples should be the same temperature as the room temperature. Prepare the pipette to equilibrate for 20 minutes before use.
When changing the volume to a lower setting, turn the knob to the desired volume setting. But when changing the volume to a higher setting, turn the selector wheel about 1/3 turn above the desired volume setting, then slowly dial back down to the desired setting. This will avoid “mechanical backlash” and assure greater accuracy.
Volume & range
Improve accuracy and precision by up to 1% by aspirating and dispensing sample within 35% to 100% of a tip’s nominal volume. Avoid setting pipettes’s volume to less than 10% of its