double digestion

[Chris Boyd]

Shu Jin (sjin at LELAND.STANFORD.EDU) wrote:
: hi, there:
: 
: I am doing double digestion with two totally different buffers. Does
: anyone know a good simple system to get rid of the first buffer and enzyme
: before use the second enzyme?! Thanks!!

Drop dialyis is the most convenient for moderate volumes (20-50 ul).

See

   Marusyk, R. and Sergeant, A. (1980) `A simple method for dialysis of
   small volume samples.' Anal. Biochem., 105, 403-404.

But, as others have mentioned, you might be able to get away with a
compromise buffer, or transit from low to high salt.

Best wishes,
-- 
Chris Boyd                      | from, but \    Medical Genetics Section
Chris.Boyd at ed.ac.uk             | not for,  /    MMC, Edinburgh Uni.,
http://www.hgu.mrc.ac.uk/Users/Christopher.Boyd  EH4 2XU, SCOTLAND