What is ICP-MS?
ICP-MS is a complex and highly sensitive laboratory instrument that is used to measure trace metals such as aluminum, copper, lead and mercury in liquid and solid samples from a diverse range of industries including the environmental, food, biomedical, chemical, petrochemical, forensic, semiconductor and nuclear fields. ICP-MS is one of the most advanced analytical instruments in use – it can detect metals in the sub parts per trillion (PPT) range. Samples are analyzed by ICP-MS typically as solutions: the sample solution is introduced into a nebulizer, where a stream of argon gas breaks up the liquid into a fine aerosol and sweeps the smaller droplets into the central channel of an argon plasma (ICP). The very high temperature of the ICP (>8000oC) causes the sample droplets to be dried and dissociated into individual atoms, which are then ionised before being extracted, through an interface, into a vacuum system. The vacuum system consists of a series of differentially pumped chambers, the final stage containing the mass spectrometer and ion detection system. In the vacuum system, electrostatic lenses keep the ions focused and separate the positively charged ions from photons and neutral particles. Analyte ions are separated by the mass spectrometer (MS), which scans rapidly across the mass range allowing each mass of interest to pass sequentially to the electron multiplier detector. The counts measured at the detector are converted to elemental concentration data. Because of its high performance, complexity and high cost (ICP-MS instruments cost $180,000 upwards), ICP-MS is very challenging to operate and labs that have an ICP-MS generally allow only their senior chemists to operate it. The key to getting the most from your investment is proper training in operation.