Ba and Sr have very strong emission in an ICP-OES instrument and should be
easily seen at the levels your ICP-MS is reporting. Is it possible the
emission is saturating your detector and your report is not indicating the
Analytical Lab Manager
APL Engineered Materials, Inc.
Urbana, IL 61802
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"PLASMACHEM-L: Analytical Chem.(ICP's, DCP's, MIP's)."
<[log in to unmask]> wrote on 12/07/2010 12:44:49 PM:
> Dear All,
> Once again the dunce cap is on and I return to the classroom
> (virtual in this case). While setting up a new ICPMS instrument a
> "random" sample of tap water (this is well water) was analyzed and
> showed strong values and nice peaks for barium and strontium. This
> holds for Ba at mass 137 and 138 and for Sr at mass 88 and 86 in no-
> gas mode, H2 mode, and He mode. "Apparent" concentration is ~ 2300
> ppb Sr and ~90 ppb Ba (the concentration for each analyte is the
> same at both masses).
> This was confirmed on a second ICPMS (no cell installed) but,
> fortunately, the ICPOES did not see Ba or Sr.
> Relieved as I am that I am not working overtop a future Superfund
> site I admit that I cannot see what species are causing these rather
> consistent readings (e.g. Ba138 = 607596 counts = 89.9 ppb, Ba 138 =
> 3874062 counts = 90.2 ppb, Sr 88 = 94962677 counts = 2390 ppb and Sr
> 86 = 10714443 counts = 2320 ppb). If it is a polyatomic problem I
> cannot find a structure(s) that make sense.
> I am assuming that some of you know these interferences by heart, so
> any insight would be much appreciated.
> Michael Murphy
> Research Scientist
> Intertek USA, Inc., d/b/a QTI
> PO Box 470
> 291 rt. 22 East
> Salem Industrial Park, Bldg. 5
> Whitehouse, NJ 08888
> Please note that all comments are my personal opinion and do not
> represent the position of my company.