From: Borries Demeler <demeler@bioc09.v19.uthscsa.edu>
  To  : Peter.Horn@umassmed.edu
  Date: Tue, 5 Dec 2000 09:45:48 -0600 (CST)

Re: epon centerpieces

> 
>     Hi,
> 
> I am very new at this , so excuse my ignorance.  I need to run some
> samples at 50,000 Beckman was vague as to wheter or not the epon
> centerpieces could handle a speed above 42,000.   Also, I have been
> having trouble with the aluminum centerpieces leaking.  I assume the
> leaking is due to the gaskets not being lined up perfectly.  Does anyone
> have any advice?
> 

We do run our epon CP's routinely at 50krpm, although Beckman doesn't
warrant them when you run them at this speed. If you do, make VERY sure
that you have almost equal amounts of solution in each sector, so the 
pressure differential at this high speed doesn't bend the septum in the
CP's.

About the aluminum CP's: Make sure the seal properly sits in the small
groove on either side of the CP before you assemble the cell.

Good luck, -Borries