ICP-MS Sample Prep

Acids

All samples will be completely digested in acid prior to running on the ICP. Refer to the Inorganic Ventures: Interactive Periodic Table for specifics on dissolving your element of interest. You will typically need trace metal grade HNO3 and in some cases a 1:1 mixture of HNO3 and HCl. Some metals require HF to dissolve, but please use caution when working with HF and always inform QBIC staff when bringing HF into the lab.

Microwave Digestion

If you are having trouble digesting your samples using a conventional hot plate, visit the Instruments page for information on how to quickly dissolve tissue sections and materials using Microwave Digestion. If you have a large number of tissue samples, you will want to purchase Teflon digestion tubes.

Standards

Common Vendors:
Inorganic Ventures
VHG Labs
CPI International

    Internal Standards: 10 ug/mL (or 10 ppm) stock. You will need one (or more) rare element(s) with a mass that is within 60 mass units of your element. For example: You are interested in silver (mass 108), so you will choose yttrium (mass 89) and indium (mass 115) as your internal standards. You will add the same amount of internal standard (typically 2-5 ppb) to each sample and calibration standard.

    Calibration Standards: 10 ug/mL (or 10 ppm) stock. Prepare multiple standards up to 100 ppb, including a blank. The detection limit for the ICP-MS is typcially in the part-per-trillion range, unless you are interested in common elements (Mg, Ca, Fe, Cu, Zn, etc.) which typcially have a detection limit in the sub-ppb range.

Metal Free Tubes and Materials

It is a good idea to use metal free tubes, tips, bottles, and other materials for ICP-MS analysis. These include: 15/50mL Centrifuge tubes, clear pipet tips, and Teflon bottles. Even these plastics will leach some metals in acid over time (refer to Moody and Lindstrom).

Contact Keith to discuss your specific samples.  http://rhlccflow.facilities.northwestern.edu/