Timothy:
It is difficult to predict exactly what will happen because of a leak
at the pump. In general, both the organic and aqueous liquids are
miscible and will be "lost" from the column equally efficiently.
When there is a leak in an HPLC system, (isocratic or gradient) there
tends to be a longer time interval before the peaks elute. This increase
in the retention time is associated with a lower pressure and a lower
volume of mobile phase passing through the column per unit of time.
Coping with HPLC leaks is one of the 'character building' joys of
chromatography....and the fact that you have paused to ask questions about
your separation rather than treat the system like a black box is a sign
that you too may be called a chromatographer. regards,
Andrew
(part-time chromatographer)
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Andrew Lyon, Clinical Biochemist email: [log in to unmask]
Saskatoon, SASK, CANADA. homepage: http://duke.usask.ca/~lyona
On Fri, 5 Jun 1998, Timothy Foley wrote:
>
> I have a question for the chromatographers in the mailbase-
>
> What affect will a small leak at the outlet valve on the pump head have on
> retention times in a gradient method? I have heard that a leak in an HPLC system
> can lead to a disproportionate loss of organic modifier (e.g. MeCN) through the
> leak. Is this true? And if so, can this phenomenon lead to longer retention
> times in a gradient run?
>
> Any comments and suggestions would be appreciated.
>
> Thanks
>
> Tim
>
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