Biotech 8/20/13 What pump would you use for a 1 or 2 ml pipet? What pump would you use for a 5 or 10 ml pipet?

How to Properly Use a Micropipettor

What are Micropipettors?! We will be using 3 different sizes of micropipettors: ◦ P20 ◦ P200 ◦ P1000 Very expensive and very fragile – USE Responsibly!!! Used to measure liquid amounts LESS THAN or EQUAL to 1 mL.

When to Use Each Micropipettor Each micropipettor has its name on the top cap. Each micropipette has a limit: ◦ P20: 0.5 to 20.0 uL ◦ P200: 20 to 200 uL ◦ P1000: 200 to 1000 uL

How to Set/Adjust the Micropipettor Adjustment knobs are on the side of each micropipettor. Red digits indicate a decimal place

How to Load and Dispense Liquids Place clean plastic tip at end of micropipettor Plunger has TWO different ‘stop’ positions. ◦ First is used to load (pick up) liquid ◦ The second (lower) is used to dispense (expel) liquid Two stop method is what creates accuracy and precision of instrument – YOU MUST BE CONSISTENT

Micropipettor Use - DOs Always use the correct micropipettor for the volume being measured Always use the correct pipette tip for each size micropipettor Use the first stop for loading Use the second stop for dispensing Release plunger slowly

Micropipettor Use - DON’Ts S2MvM S2MvM NO Double Dipping ◦ When in doubt – CHANGE TIPS!! Don’t place tip into liquid too deeply. Use the two stops appropriately Don’t squirt liquid out too quickly Don’t point tip up – this will contaminate the barrel

Measuring Very Small Volumes Lab We will be spending the next few days practicing with the micropipettors. This is a skill we will use consistently the rest of the year!