Getting from tube A to tube B (the Biochemistry Transit System 🤓🙃) Probably ~90% of what my #lifeinthelab entails is transferring liquid from one place to another, so it’s about time we talk about #PickingPipettes #EquippedToExperiment THREAD 1/n
— Brianna Bibel (@biochem_bri) April 24, 2018
A pipette is a piece of lab equipment that you use to draw up and dispense liquid. They come in many sizes and types. In this thread I’ll introduce you to some go the kinds we use. #PickingPipettes #EquippedToExperiment 2/n
— Brianna Bibel (@biochem_bri) April 24, 2018
This is a “classic” Pasteur pipette and they’re basically as simple as pipettes get - glass tubes w/a narrowed tip ⏩ attach a rubber bulb to the top to create suction to suck up liquid (people used to do this with their mouth - DON’T!) #PickingPipettes #EquippedToExperiment 3/n pic.twitter.com/CqxXX1jDfe
— Brianna Bibel (@biochem_bri) April 24, 2018
I don’t use Pasteur pipettes often because you can’t measure w/them, but they’re good for adding liquid💧by 💧like when you’re trying to adjust the pH of a solution & have to add drops of acid or base until it settles on the pH you want #PickingPipettes #EquippedToExperiment 4/n
— Brianna Bibel (@biochem_bri) April 24, 2018
We also have plastic transfer pipettes ("eyedroppers”) that are similar to the Pasteur pipettes but they’re plastic and all-in-one (no bulb required) #PickingPipettes #EquippedToExperiment 5/n pic.twitter.com/NkVd2APKBx
— Brianna Bibel (@biochem_bri) April 24, 2018
If I want to transfer volumes ranging from ~2mL-25mL, I use serological pipettes. These pipettes have measurement lines so you can move around measured volumes of liquid. #PickingPipettes #EquippedToExperiment 6/n pic.twitter.com/CWHoy0iDOr
— Brianna Bibel (@biochem_bri) April 24, 2018
You can use rubber bulbs (bigger ones) with serological pipettes, but (thankfully) we have electric “Pipet-Aids” to help. The top button draws up fluid and the bottom button releases it #PickingPipettes #EquippedToExperiment 7/n pic.twitter.com/cER7DpPz6p
— Brianna Bibel (@biochem_bri) April 24, 2018
The Pipet-Aid is powerful so thankfully these serological pipettes have cotton plugs to prevent you from drawing up liquid too far and damaging the Pipet-Aid #PickingPipettes #EquippedToExperiment 8/n pic.twitter.com/L9Pi7T48hb
— Brianna Bibel (@biochem_bri) April 24, 2018
For transferring volumes 1mL or less, we use micropipettes. These are probably our most-used pieces of equipment. They come in multiple volume ranges. When possible, you want to choose a range the volume you want is in the middle of #PickingPipettes #EquippedToExperiment 9/n pic.twitter.com/dSQPYF69Es
— Brianna Bibel (@biochem_bri) April 24, 2018
We refer to these micropipettes in terms of the largest volume they can transfer - for example, this pipette can transfer volumes from 2-20µL (a microliter (µL) is 1000X smaller than a mL) so we call it a P20 #PickingPipettes #EquippedToExperiment 10/n pic.twitter.com/9BeQ6m60Pv
— Brianna Bibel (@biochem_bri) April 24, 2018
To use a micropipette, you push down the top button, place the pipette in liquid then release the button. Then move it to where you want it and push back down to dispense. #PickingPipettes #EquippedToExperiment 11/n
— Brianna Bibel (@biochem_bri) April 24, 2018
Once you’re done, you push the ejection lever to eject the tip into a waste container (old salts containers work great) #PickingPipettes #EquippedToExperiment 12/n pic.twitter.com/sNRRJ2xNNs
— Brianna Bibel (@biochem_bri) April 24, 2018
Speaking of tips, different size micropipettes use different size tips. We buy them in “racks” that we refill our tip boxes with #PickingPipettes #EquippedToExperiment 13/n pic.twitter.com/sTRvg1Sdzx
— Brianna Bibel (@biochem_bri) April 24, 2018
We also have filter tips that we use when we’re pipetting sensitive samples (like RNA) or radioactive samples. #PickingPipettes #EquippedToExperiment 14/n pic.twitter.com/CpXFNwkEC5
— Brianna Bibel (@biochem_bri) April 24, 2018
Pipetting the same volume over and over can be hard on the thumb, so we have a repeater pipette. It has different size tips and you can pull up more liquid then you need and have it eject a set amount every time you push down #PickingPipettes #EquippedToExperiment 15/n pic.twitter.com/WTMvAB4h8i
— Brianna Bibel (@biochem_bri) April 24, 2018
So far, I’ve showed you single-channel micropipettes, but they also make multi-channel micropipettes that are thumb-savers when you have to pipette into multi-well plates. Here’s an 8-channel and a 12 channel. #PickingPipettes #EquippedToExperiment 16/n pic.twitter.com/y8zIKEC63H
— Brianna Bibel (@biochem_bri) April 24, 2018
If we need to pipette a whole 96-well plate at once, we have this guy! #PickingPipettes #EquippedToExperiment 17/n pic.twitter.com/8Ae30Gvx9b
— Brianna Bibel (@biochem_bri) April 24, 2018
And if we need to pipette really really tiny volumes onto crystallization trays, we have this “Mosquito” robot #PickingPipettes #EquippedToExperiment 18/n pic.twitter.com/fYTOahMsH6
— Brianna Bibel (@biochem_bri) April 24, 2018