Tricks for pipetting detergents??

Gary Smyly hutchins at
Sun Aug 18 14:33:29 EST 1996

Paul Wakenight (pw at wrote:
: I'm sure everyone has tried to pipette NP40, etc.  What a mess.
: Outside of using a graduated cylinder, is there anyway to do this 
: accurately?

The other suggestions are good.  I would add:

1. You can buy 'wide-bore' pipet tips from Fisher and other suppliers.
They work much better for viscous solutions.

2. You can use a 'reverse-pipetting' method I originally learned from a
Gilson manual, I think.  Basically, you push the plunger all the way down
(as if to expel solution), then draw up.  Of course, you have to wait a
week or two for the viscous goo to get inside your pipet tip.  Then, to
dispense, push down to the first stop (i.e., to measure out the set
amount).  It works, but requires some practice and patience, and you need
to be careful not to contaminate the barrel of your pipettor in the first

Jim Hutchins    hutchins at   hutchins at
Annie 1/3 NA, 2/3 CD, HIC *** Kodiak SC (Snuggle Certified)
"Morde diem" ****** Annie's motto ****** "Bite the Day"

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