Concerns About OsO4 Formation in Multi-element Standards

Hello Dr. Gaines,

I recently bought some individual standards from IV including Os@100ug/mL. I was planning on making an intermediate standard in a 2%HNO3/0.5%HCl acid matrix. This will be a multi-element standard at varying concentrations. I'm concerned about the OsO4formation but I'm wondering if the presence of the other elements along with the 0.5%HCl will minimize this formation.

The other elements will be As @ 0.15 ug/mL Cd @ 0.05 ug/mL Pb @ 0.10 ug/mL Hg @ 0.15 ug/mL Cr @ 2.5 ug/mL Cu @ 25 ug/mL Mn @ 25 ug/mL Mo @ 2.5 ug/mL Ni @ 2.5 ug/mL V @ 2.5 ug/mL Pd @ 1.0 ug/mL Pt @ 1.0 ug/mL Os @ 1.0 ug/mL Rh @ 1.0 ug/mL Ru @ 1.0 ug/mL Ir @ 1.0 ug/mL This will be used for ICP-MS analysis. Specifically the new Heavy Metals Method. The 2%/0.5% solution is what I hope to introduce to the instrument so I suppose the intermediate standard can be made in HCl only?

I do not suggest the addition of any nitric acid.

Os will oxidize to the tetroxide - slowly- and the results by ICP will come out very high because of the volatility of the tetroxide and resulting nebulization efficiency approaching 100%. Only use HCl with Os intermediates.

Serving you in chemistry,

Paul R. Gaines, Ph.D.
CEO of Inorganic Ventures & Fellow Chemist

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