Performance characteristics of a low volume spray chamber with a micro-flow nebulizer for ICP-MS

Abstract

Inspired by the original work of Todolí et al. in designing a torch integrated sample introduction system (TISIS) for ICP-AES, the authors have modified this design for use with ICP-MS. A microflow concentric nebuliser has been coupled with a single pass low volume spray chamber that can be clipped directly onto the base of a standard ICP-MS torch. The memory effects are very low: a 10 µg l⁻¹ tune solution containing Co, Ce and Tl was found to have washed out within 4 s. Matrix effects were reduced significantly across the mass range for a 10-fold diluted sea-water sample, with the signal being suppressed by only 10–20% compared with the response in ultra-pure water; detection limits were found to be higher than with the normal set up, with the instrument tuned to “robust” conditions. Finally, it was shown that the low dead volume and low flow rate meant that transient signals could be acquired easily, by flow injecting 100 µl of a standard and obtaining a flat topped peak with a 50 s signal plateau.