Summary

This is a improvised pipette for DIY biology using a drinking straw. Use this to pipette small volumes until you get a real micropipette!

Instructions

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