by cpendlebury, published
This is a improvised pipette for DIY biology using a drinking straw. Use this to pipette small volumes until you get a real micropipette!
See it in action here: http://youtu.be/Q6cFps88G9M
- Print StrawPipette.stl
- If necessary, clean up hole so straw slides in easily. The straw should stay in snugly, but shouldn't crush the straw.
- If required, sterilise some drinking straws.
- Insert straw and use pipette:
i. Insert into liquid, cover top of straw with thumb.
ii. hold thumb on straw while transferring liquid.
iii. release thumb to dispense liquid.
- Change straw when you would change a micropipette tip.
It operates in the range 200Î¼L to 1000Î¼L, and with practice you should be able to reliably dispense liquid in 100Î¼L increments.
Volume dispensed = Ï€ radius of straw^2 depth into liquid