Inductively coupled plasma mass spectrometry (ICP-MS) can be utilized for both quantitative and semi-quantitative analysis of most elements in the periodic table and is commonly employed in a wide range of geologic, environmental, biological, and industrial applications. The primary strengths of ICP-MS lie in its ability to provide rapid, sensitive, and precise multi elemental analyses across a high dynamic range enabling measurement of elemental concentrations ranging from sub parts per billion to hundreds of parts per million in a single run. The EMES is equipped with an Agilent 7900 quadrupole ICP-MS for determination of trace, minor, and major elements in aqueous solutions and acid digestions. 

Sample preparation for ICP-MS is dependent upon the sample type and users analytical needs. EMES staff can provide assistance into sample preparation procedures; however, it is ultimately the responsibility of the user to ensure that samples are prepared to meet their analytical needs and do not result in contamination and/or loss of analytes. Preparation procedures should be discussed with EMES personnel during experimental design to ensure their suitability for analysis on our instrument. Sample preparation facilities, including an Anton Paar Multiwave 5000 Microwave System, are available to lab users and can be utilized to prepare a wide range of sample types. The following are some general guidelines to consider when preparing samples to be analyzed in the EMES:

• All reagents used in sample preparation for ICP-MS should be high purity and certified for trace metal analysis (for ppb level analyses most commonly performed in our lab Fisher TraceMetal grade or equivalent is required and Optima grade may be ideal if analyzing near detection limits).

• A procedural blank should be prepared following the same process as unknown samples to ensure no contamination during sample preparation.

• Samples must be free of particulates as the presence of any particulates may clog the sample introduction system. If necessary, particulates can be removed from the sample through filtration or centrifugation and decanting.

• Samples should preferably have less than 200 parts per million total dissolved solids (TDS) although higher TDS concentrations may be possible if discussed with EMES personnel prior to submission. Samples with TDS above this range may be diluted to the appropriate range.

• Samples should ideally be in a 2% HNO3- matrix. In some cases, other matrices may need to be utilized, but total acid contents must remain below 5% and cannot include hydrofluoric acid.

• Estimated elemental concentrations for the samples should be provided to enable selection internal standards and calibration concentrations. If elemental concentrations are unknown, they can be determined using a semi-quantitative analysis on the ICP-MS.

• While most elements are stable in dilute acid solutions it is generally better to analyze samples quickly after collection or preparation.

• Samples should ideally be stored and submitted in 15 mL polypropylene test tubes (Falcon tubes are a good option, but other brands will also work).

• A sample volume of 10 mL is preferred. Smaller sample volumes may be possible if necessary but should be discussed with EMES staff prior to submission