It seems like every movie that needs a shot of a scientist doing their sciencey-thing either gets the person to pour one pretty liquid from one flask into another or to stare intensely at a test tube with a look of knowing so much more than you ever could.

Another favorite shot is of someone using a pipette, but us scientists get all hot and bothered shouting at the screen “that’s not how you do it!”

Here is a list of ways NOT to use this common tool and it is as much for screenplay writers as it is for scientists learning a new technique.

1. Forgetting your head

When using a pipette, always use a tip. Always! How many beautiful pipettes have been ruined by sheer incompetence…

2. The wrong guy for the job

Make sure your tip is the right one for the volume you are pipetting.  You don’t want to accidentally suck liquid up into the chamber.

3.  Pushing it too far

Once the tip is secured, aspirate the sample by pushing down the top of the pipette to the first position, not all the way down or kindly leave the lab in shame!

4.  It’s a pipette, not a plunger

To dispense the sample from the pipette, slowly push down using your thumb. Do NOT pump up and down to get every last bit! Your pipette knows how to get the work done and does not require encouragement.

5.  Leaving it lying around

Never ever leave a pipette hanging around where it could become contaminated. A handy trick if you don’t have one of the revolving holders or a hook on your pipette is to use a large paper clasp! If you clip it to a shelf and then hang the pipette between the two metal rings facing downwards, it works very well.

6.  Using it as a backscratcher

Do not use the pipette to get at that annoying itch on your back. I know, I know, it might be tempting – but I’m sure an obliging coworker will do the honors. It might just be worth asking anyway to see their reaction.

7.  Holding it wrong

A pipette is not used like a syringe and under no circumstances should it be held as one. Hold the pipette by resting the lip on the index finger. Then wrap your fingers around it place your thumb on the thumbutton. It is easiest to pipette at an angle by rotating your hand away from your body and holding the sample (away from your face) at an angle also.

8.  Dialing it up

Be sure to set the pipette volume within the range specified for the pipette. Do not attempt to set a volume beyond the pipette’s minimum or maximum values as this will damage the micrometer gears.

9.  The quick release

Use your thumb to slowly control the plunger. Do not let the plunger jump up as this isn’t good for the piston and the plunger can get contaminated.

10.  But, but TV told me to do it this way

Don’t take tips on pipette use from TV. Nope nope nope!

While you’re here, why not download our handy pipette cleaning guide and share it with your lab buddies, or stick our pipette care poster up in your lab? They’re free!

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