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by sopchi 892 days ago
I am surprised there is on mention of rubber bulbs. If the main concern is safety, as the beginning of the article seems to imply, the rubber bulb would have been enough of a solution. The micropipette solves mostly all the other concerns: speed, repeatability, avoidance of contamination, ease of use one-handed. A great invention for sure. Why would they even mouth pipette if they can use a rubber bulb? Is it that the rubber bulb was somehow invented later? Did you encounter anything about that when researching this topic?
1 comments

it's all about control. You get a lot more feedback and accuracy with your mouth.
OK, I see. I still find that surprising because I would imagine having the pipette hanging from your mouth doesn't allow ou to really see what is going on if you are really trying to hit a target volume. I would have thought the feedback you need is visual.
Oh. I'm actually looking at the pipette tip under a microscope (in my case it's clear glass that I pulled to a fine tip using heat) and I can see the tardigrade get sucked into the tip when I gently pull with my mouth. And then I can see it whoosh back out when I push. The actual volume doesn't matter, just that I pick a single tardigrade and place it where it needs to go.

The other folks pipetting by mouth are actually looking down at the tube and see the fluid volume reaches a particular well-defined line on the glass pipette. If you can taste the fluid, you've gone too far.

I just looked up photos of people pipetting by mouth. They use tubes.