we have had discussions in the past regarding leeching of "detergent like"
polymers from tubes that swamp ESI spectra.
I thought I was using relatively MS clean tubes until recently when I have
been undertaking an exhaustive study of a protein digest by nano-ESI MS/MS
where I have had, because of the size of the project, to store fractions
for a few weeks at -20 degrees C.
I have noticed that fractions containing more than about 25% acetonitrile
contain these pesky polymers after about a weeks storage. The polymers are
not present in the original solvent and their time dependent appearance
seems also to be organic concentration dependent.
Apart from the obvious solutions like doing the experiment quicker or
removing the organic solvent by evaporation prior to storage, does anyone
out there have other suggestions.
In particular, is anyone using a tube (specific make and model required
here) where one can store say 60% acetonitrile for weeks without extracting
polymeric material from the plastic?
Regards....Ken
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Ken I. Mitchelhill
The John Holt Protein Structure Laboratory
St. Vincent's Institute of Medical Research
41 Victoria Parade
Fitzroy 3065 Victoria
AUSTRALIA
Telephone: 61-3-9288 2480
Facsimile: 61-3-9416 2676
Email: k.mitchelhill@medicine.unimelb.edu.au
Laboratory: http://www.medstv.unimelb.edu.au/WWWDOCS/SVIMRdocs/JHPSL.html
ABRF: http://www.abrf.org
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