ICP Quality Issues

Chemical Compatibility

It's important for the multi-element blends to be compatible with the containers in which they are prepared and stored. It's equally important that they are compatible with the introduction system of the instrument(s) used to analyze the blend and with the other analytes within the blend. Some points to consider:

• Is the matrix of the standard compatible with glass or quartz? Glass is not compatible with HF and caustic matrices.
• Are there possible reactions between the chemical components of the standard that may adversely alter the standard with time? Photo-reduction of Ag in high HCl matrices, ppt of Ag in trace Cl matrices, ppt of Pb and Ba with trace levels of sulfate or chromate, ppt of the alkaline and rare earths with F^- in HF matrices, ppt of fluorinated elements like Sn(F)_x^-y in the presence of elements that would complex with the fluoride and therefore 'pull it away' from the metal stabilized as the fluoride complex, etc.
• Does the standard contain components that could form volatile compounds? A classic example is the oxidation of osmium chloride to the very volatile and toxic OsO₄ when nitric acid is added. Volatile compounds may not be lost from the standard solution but will give false high readings due to a disproportionate amount of the element making it to the plasma where the nebulization efficiency is greater due to the added mode of transport to the plasma as the vapor state.

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