Isn mass spectrometry an expensive, difficult, non-quantitative, low sensitivity method that is dependent on the specific chemical composition of the biomarker?
Use of the term “mass spectrometer” in the bioanalytical community almost invariably evokes recognition of organic (protein) mass spectrometry. This is quite distinct from the present technology. The mass spectrometer used in this application is an inorganic (elemental) mass spectrometer, specifically an ICP-MS. Conventional organic mass spectrometry attempts to recognize proteins or peptides through mass fingerprints with reference to massive libraries, and is encumbered by sample-dependent sensitivity (both the specific functionalization of the biomarker and ionization interference by the cell matrix). Accordingly, it has drawbacks inherent to the complexity of the instrument, sample preparation and data analysis. ICP-MS provides virtually sample-matrix-independent sensitivity, absolute quantification, high dynamic range, excellent resolution of mass channels, and simple interpretation (only the elements of the periodic table). It has a reputation for great ruggedness and simplicity
