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Posted: Fri Feb 19, 2010 11:14 am
by Peter Apps
Hans, you should patent that, I'm sure there would be a market for it :lol:

Peter

Posted: Fri Feb 19, 2010 3:24 pm
by Jumpshooter
I may float the suggestion of appending a high temp bake off at the end of run; would USP call this a "modification" or a "revision" or a "method change".

Peter: very interesting work on the scented dog trails in Africa.

HMeuller: quite humorous about being struck down by lightining :)

Posted: Sat Feb 20, 2010 8:43 am
by Peter Apps
Hi Jumpshooter

If you are seeing sharp ghost peaks then baking the column is not going to help - the fact that they are sharp means that they are being introduced at the injection. A longer hold time at maximum temperature helps with ghosts that would have eluted late in the chromatogram if they had been given enough time, but these are always broader than the peaks around them.

The changes you need to make are more syringe washing (possibly with an extra solvent), more frequent septum changes and liner changes, and if that does not work chop a meter off the inlet end of the column.

I'd would hardly call the wild dogs "scented" - "stinky" would be more like it :lol: , but fascinating none the less !

Peter