Inductively Coupled Plasma Mass Spectrometry (ICP-MS)

Inductively coupled plasma mass spectrometry (ICP-MS) is one of the most sensitive multi-elemental analysis techniques available that can detect elements at milligram to nanogram levels per liter. As such, it is recognized as one of the most important analytical techniques in a variety of industries including, but not limited to, impurity monitoring in semiconductor industries, environmental monitoring, geochemical analysis, mining and metallurgy, pharmaceutical analysis, among others. ICP-MS offers extremely high sensitivity (i.e. low detection limits) for most of the elements in the periodic table.

Solid samples are generally dissolved or digested before analyses. The inductively coupled plasma is a very strong ionization source that fully decomposes the sample into its constituent elements and transforms those elements into ions. These ions then are subsequently extracted and accelerated into a mass analyzer for detection. Ion intensity acquisitions are then converted to concentration units by comparison with calibration standards. This technique is especially powerful for accurate chemical analyses.

Ideal Uses of ICP-MS

Trace and ultra-trace elemental analysis (ppm – ppb) of solids, liquids, surface contaminants, leachable and extractables
Investigative analyses (R&D, FA, forensic)
Production support
Regulatory and compliance analysis

Strengths

Most of the elements in the periodic table can be measured in single analysis, with high precision and accuracy
Diverse representative sampling methods enabling high sensitivity detection of surface contaminants, leachables, extractables, or bulk impurities
Applicable to a wide variety of samples, from liquids to solids, from inorganic to organic, from simple compositions to composites
Dynamic Reaction Cell (DRC) technology virtually eliminates polyatomic isobaric interferences
The combination of ICP-OES and ICP-MS is very powerful for determining a wide range of elemental concentrations, from major components to very low levels (typically sub ppb) with high accuracy and precision

Limitations

Sample preparation – digestion procedures of solids are often complex and time consuming
Polyatomic mass interferences
Atmospherics and light halogens

ICP-MS Technical Specifications

Signal Detected: Positive ions of stable isotopes
Solid Sample Size Requirement: 250 mg to 1 gram
Typical Solution Volumes Sampled: 1 – 10 mL
Elements Detected: Most of the elements in the periodic table
Reducing the Effects of Interferences: Matrix separation, collision mode, reaction mode, Dynamic Reaction Cell (DRC), Kinetic Energy Discrimination (KED), triple-quad
Typical Detection Range: ng per L
Imaging/Mapping: No