ICP & ICP-MS Standards
ICP, or Inductively Coupled Plasma, is a spectrometric technique utilised in the identification and detection of trace metals content in a wide variety of matrix. Two main methods of detection commonly used, ICP-OES (Optical Emission Spectroscopy) and ICP-MS (Mass Spectroscopy).
ICP-OES is mainly used for samples with high total dissolved solids (TDS) or suspended solids and is therefore, more robust for analyzing ground water, wastewater, soil, and solid waste although it can be used for drinking water analysis as well. In general, ICP-OES is used to measure contaminants for environmental safety assessment and elements with a higher regulatory limit. ICP-MS, on the other hand, is especially useful for analyzing samples with low regulatory limits. In addition, ICP-OES has much higher tolerance for TDS (up to 30%). ICP-MS has much lower tolerance for TDS (about 0.2%) although there are ways to increase the tolerance. Although both ICP-OES and ICP-MS can be used for high matrix samples, sample dilution is often necessary for use on ICP-MS. In addition, if a sample contains analytes of great difference in concentration, ICP-MS has wider dynamic linear range so the sample may not be diluted to detect these elements at the same time.
ICP-OES quantitation is based on the measurement of excited atoms and ions at the wavelength characteristics for the specific elements being measured. ICP-MS, however, measures an atom’s mass by mass spectrometry. Due to the difference in metal element detection, the lower detection limit for ICP-MS can extend to parts per trillion (ppt), where the lower limit for ICP-OES is parts per billion (ppb).
We assay our ICP standards and ICP-MS standards by validated ICP and wet chemical procedures to obtain the certified value. All standards we make for ICP and ICP-MS are traceable specified NIST SRMs. The NIST-traceable density is shown on the Certificate of Analysis, along with 3-4 pages of additional data.
ICP-MS is becoming a workhorse for metal analysis in water not only because it offers lower detection limit. The following features also contribute its wide range of environmental applications:
- Wide dynamic range
- Efficiently remove polyatomic spectral interferences using collision cell technology
- Rapid semi-quantitative analysis
- Isotopic analysis
- Speciation capability
ICP-OES is used for all the matrices of environmental samples especially for high-matrix samples. The following features also contribute its wide range of environmental applications:
- Only analytical grade reagents are sufficient
- Simpler method development does not need a specialist with highly technical expertise
- Overall is a cheaper option if the elements do not need lower detection limit that ICP-MS delivers
- EPA 200.5
- EPA 200.7
- EPA 6010
- ISO 11885:2007
- ISO/TC 190/SC3/WG1 N0252
- NPR 6425:1995
- NEN 6426:1995
- EN 12506: 2003