Blending elements for ICP, ICP-MS, ICP-OES standards

Blending stock standards for your custom in-house internal standard takes a little time, but it is very economical provided you already have the stock standards available. Start by pre-rinsing all glassware/plasticware with either dilute nitric or hydrochloric (depending on which acid makes up your end matrix). Then, rinse 3X with high purity DI water. It is recommended to use class A calibrated volumetric pipettes to measure and dispense your elements, which should be thoroughly acid rinsed as well.

Note: Stock solutions containing any HF must be made in plastic flasks and dispensed with plastic pipettes instead of glass!

Complete your calculations and have a partner review your work before proceeding. Depending on the final volume of solution, calculate the balance of matrix solution (eg 2% nitric) needed, and add your matrix to the flask with a little DI water to prevent concentrated stock from possible precipitation with other elements (which is likely when in higher concentrations such as 50,000 ug/ml, and even 10,000 ug/ml). Generally, keep total concentration of blended elements below a maximum of 30,000ppm (ug/ml). Below 20,000 is even preferred. Finally, QS to volume with high purity water if there is any room left in the flask.

For your convenience, Exaxol offers high purity trace metal grade water here.