Drain a pipette with tip against the inner wall of the receiving vessel. Never forcibly expel any hazardous material from a pipette.
Carefully ejectthe disposable pipette tips to minimize aerosol formation. A wetted towel in the bottom of the dispensing container (which is often a glass beaker) will keep the pipette tip from bouncing around in the container, thereby minimizing aerosol production.
Place reusable pipettes horizontally in a pan filled with enough liquid disinfectant to completely cover them.
Mouth pipetting is prohibited; mechanical pipetting devices are used.
Never put a pipette in your mouth. Draw the liquid into the pipette using a rubber bulb or pipette pump. Never withdraw a liquid from a near-empty container. If you attempt to fill a pipette under conditions where air can enter the pipette, the liquid will shoot up into the bulb or pump.
Select forward or reverse pipetting based on the liquid. Depress the plunger to the first stop, immerse the tip into the liquid, and aspirate by releasing the plunger. Remove the pipette from the liquid and depress the plunger to the second stop to dispense the entire contents.
Set the volume within the range specified for the pipette. Hold the pipette so the "grippy finger rest" rests on your index finger. To maximize accuracy, the pipette, tip and liquid should be at the same temperature. Check that you are using tips recommended for this pipette.
The most common hazards associated with pipetting procedures are the result of mouth suction. Oral aspiration and ingestion of hazards associated with pipetting procedures are the result of mouth suction.
When you use poor pipetting technique the risk of introducing error increases. Poor pipette technique may result in systematic error which is manifested as inaccurate volume transfers. Inaccurate volumes may alter the concentration of reaction mixes leading to failed experiments.
Choosing the correct pipetting technique helps securing the accuracy and precision necessary for reproducible, reliable results. Especially when pipetting small volumes the influence of the pipetting technique can have tremendous effects on the experimental result.
In terms of efficiency, reverse pipetting is generally more efficient than forward pipetting, especially when transferring large volumes of liquid. This is because the technique allows for the efficient transfer of the liquid, and it is not necessary to refill the pipette multiple times to transfer the desired volume.
The practice of mouth pipetting has been recognized as a hazard since the late 19th century, but it persisted in biomedical research laboratories for many years. Mouth pipetting can lead to the inhalation or ingestion of harmful substances, increasing the risk of exposure to pathogens and toxic chemicals.
Working at a constant temperature minimizes variation of pipetted volume. Temperature differences cause thermal expansion and shrinking in the air space. After temperature equilibrium, the influencing factor is liquid density. Cold liquid is more dense and hot liquid is less dense compared to room temperature liquids.
Introduction: My name is Lakeisha Bayer VM, I am a brainy, kind, enchanting, healthy, lovely, clean, witty person who loves writing and wants to share my knowledge and understanding with you.
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