Thermo Jarrell Ash takes a different strategy with Quadrion by adding an optical emission spectrometer accessory to create an instrument that prescreens samples for concentration range. Or the analyst can set up criteria by which to select either optical or mass analysis based on a particular element or concentration range. All instruments come with a conventional nebulizer for liquid samples. As a rule, problems develop when total dissolved solids in samples exceed 0.1-0.5. The problem manifests itself in the orifices leading into the mass spectrometer.
Ions enter the mass spectrometer through two sequential orifices, the sampler and skimmer cones.
In effect, these are controlled leaks against which the vacuum pumps must work to maintain a good vacuum to minimize unwanted background ions. The sizes of these orifices also affect the ratio of analyte ions to oxide interferences. It is these orifices that clog when high levels of solids are introduced. The cones have a finite lifetime because of erosion and chemical corrosion. Direct introduction of solids offers a different set of problems.