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Re: [IP] Bubbles in reservoir

Nancy, you could achieve pretty much the same thing if you just left the
bottle out overnight.  It's a basic problem in physical chemistry.  More
air can be dissolved in cold water.  So if you fill up a syringe with cold
insulin, then when it warms up to room temperature (or higher close to the
body), then the air will come out of solution.  There's no way to avoid
this.  I went back and calculated just how much air could come from a 3 ml
full syringe as it went from 4 degrees C in the fridge to room temp at 24
C.  Over this temp range about 30 microliters of air must  come out of
solution.  That's surely enough to give lots of champagne bubbles-- perhaps
more like beer bubbles :-).  So that's why what you're doing works, but
letting the bottle warm first will accompish the same thing.

<<<<<<<Bubbles used to drive me nuts.  Now, I draw up the insulin the night
a change day, and just leave the cartridge sitting upright on the kitchen
table till morning.  By morning, all the bubbles are one big airspace at the
top of the cartridge, and I just push them out and hook the tube on.  Makes
life a little easier.
Nancy Morgan, Jenna's mom>>>>>>>>>>>>


Insulin-Pumpers website http://www.insulin-pumpers.org/