Behaviour of arsenic and selenium in an ICP-QMS with collision and reaction interface

Abstract

The performance of a collision reaction interface (CRI) for minimization of spectral interferences on analytical signals of ⁷⁵As⁺ and ⁷⁶Se⁺, ⁷⁷Se⁺, ⁷⁸Se⁺, ⁸⁰Se⁺ and ⁸²Se⁺ isotopes was evaluated by using H₂ and He gases introduced through the sampler or skimmer cones of an inductively coupled plasma quadrupole mass spectrometer (ICP-QMS). Different gas flow rates were tested employing reference solutions prepared either in hydrochloric acid or in water soluble tertiary amines (CFA-C) media as carbon source. A hydrogen gas flow rate at 60 mL min⁻¹ introduced through skimmer cone was effective for minimizing polyatomic interferences on ⁷⁵As⁺ and Se isotopes, except for ⁸⁰Se⁺. The use of He introduced through sampler or skimmer cones had a minor effect on the minimization of interferences when compared to the use of H₂ gas. Moreover, it was observed that the gas introduction through the sampler cone had no effect on interferences when using gas flow rates up to 80 mL min⁻¹ for both gases evaluated. Based on these results, it can be recommended to use H₂ gas introduced through skimmer cone of the CRI for correcting polyatomic interferences on ⁷⁵As⁺ and Se isotopes in matrixes containing up to 2% v v⁻¹ chloride.