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I am trying to figure our how I can make my own calibration standards for organic ICP analysis. I assume that I need organometallic compounds to mix with base-oil/mineral-oil to prep the standards, but I can not figure out what specific compounds are commonly used for the different metals (example: For Na, maybe Sodium isopropylcyclopentadienide?). I have looked online and through some analytical chem texts but no luck. Any source for this information would be greatly appreciated.

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  • $\begingroup$ Well what metals other than Na? My first thought was what organic medium? Typically water is used as the solvent and the metals will be low concentration. So the viscosity of the samples and standards are the same. If you look at the signal from 1 microgram per liter of Na in ethanol, and hexane and mineral oil I'd absolutely expect different signal strengths for Na. $\endgroup$ – MaxW Sep 12 '16 at 19:55
  • $\begingroup$ MaxW, K, Fe, Al, Ca, Cu, Ni, Si, V just to name a few... the matrix is mineral oil and hence should be the calibration standards. I purchase the standards from a distribute but would rather prepare them myself. $\endgroup$ – Ochemwiz Sep 12 '16 at 20:31
  • $\begingroup$ 8 elements out of 92 and that is just a few?!? $\endgroup$ – MaxW Sep 12 '16 at 22:21
  • $\begingroup$ Buy the standard. The hassel you will have with water/impurities/.... is propably too much to bother with. You would need highly purified reagents, oranometalic compounds which never even saw some oxigen/water form a mile distance... Also, normally ICP does a sample preparation either by burning the sample or using strong acid. Does the counter ion of the metals really matter? (rhetoric question. there are some cases that matter, but most probably not organic). $\endgroup$ – Julian Sep 13 '16 at 11:32
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    $\begingroup$ I agree with @Julian, better to buy stock solution of different Metal ( 1000ppm) and prepare you standard solution accordingly. after drawing calibration curve, you can save this program and don't need to do calibration every time for comparison of your results. In my opinion oganometallic compounds can,t be used for the preparation of standard solution in ICP-OES/OAS. $\endgroup$ – Khan Sep 13 '16 at 12:30
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Running an ICPOES or ICPMS on organic solvents is not easy, you may have problems such as coke / carbon deposits in the torch.

Also I would like to point out that sodium dicyclopentadienide is very sensitive to oxygen, it decomposes with great ease on contact with air. Ask almost anyone who has made ferrocene in the lab about this question.

I would like to suggest that you consider making an emulsion in water of the organic solution using a detergent such as triton-x100. I have heard of this method for running organic samples in a normal ICPMS but I have never tried using it.

In the ideal world what I would do would be to use a wet combustion (maybe use a acid digestion bomb such as a Parr 45 ml bomb) to convert the organic sample into a aqueous sample.

Another option would be to use neutron activation anaylisis, but these days it is very hard to find a strong neutron source suitable for this type of work. You would have to seal up samples in quartz tubes. I will warn you that even with a nuclear reactor and a good gamma spectrometer this type of work is far from trival.

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