Mass-spectrometry with inductively coupled plasma ion source is widely applied for the determination of elemental composition and isotope ratios of liquid and solid samples in geological, chemical, semiconductor and other technical sciences. It is a very flexible technique allowing to analyse the concentration of most elements of the periodic table down to a (sub)ppt-level in liquid samples and down to a (sub)ppb level in solid samples. It also allows for a high sample throughput and usually requires little sample preparation compared to the alternative techniques, such as TIMS or SIMS.
Sample to be analysed is introduced into a torch, where the argon gas flows under atmospheric pressure through a fast oscillating magnetic field. Charged particles can be introduced in the argon flow by means of a Tesla coil or a piezoelectric device, resulting in the appearance of eddy currents in the argon gas. Resistive heating of the gas by the eddy currents promotes its further ionisation and results in the formation of a stable argon plasma in the torch, having a maximum temperature of c. 8-10000 K. Samples to be analysed are injected in the plasma either as very small droplets obtained by the nebulisation of solutions, or as tiny solid particles formed by the ablation of solid samples using a laser. These droplets (particles) are vaporised and ionised in the torch, and the so-formed ions are transported in the mass-discriminator, which separates ions according to their mass-to-charge ratio. The ions of interest are counted by the detector. Quantitative, accurate and precise results can be obtained using appropriate analytical protocols and standardisation techniques on a well-optimised instrument.
Our laboratory has two ICP-MS facilities:
Quadrupole spectrometer Elan 6100 DRC
The quadrupole spectrometer Elan 6100 DRC can be interfaced to a GeoLas 200M ArF excimer ablation system or used alone for the analysis of liquid samples. It is used in applications that do not require the lowest possible detection limit. These applications include the laser ablation analysis of lithium tetraborate glass discs and minerals, as well as the analysis of a wide variety of natural solutions and dissolved solid samples (mine tails, natural and underground waters, carbonates).
Sector-field spectrometer Element XR
The sector-field spectrometer Element XR can be interfaced to a NewWave UP-193 ArF excimer ablation system or, again, used alone for the analysis of liquid samples. It is used for the laser ablation analysis of very low element concentrations in minerals like olivine, garnet, orthopyroxene, mica and feldspars, and particularly for the U-Pb dating of zircons. It is also episodically used for the analysis of low element concentrations in solutions. This instrument has a very high sensitivity and low instrumental background compared to an Elan 6100 DRC and most other quadrupole machines.
Our laboratory has a wide experience in the analysis of geological samples and also carries out analyses for chemical and technical research institutions, as well as for commercial entities.
The operation of the spectrometer and the evaluation of the accuracy of the acquired results are facilitated, if the user has a background in the ICP-MS. We provide yearly courses on the ICP-MS, which our master and doctorate students are required to take.