Simultaneous Detection of Ruthenium and Osmium by Photochemical Vapor Generation-Inductively Coupled Plasma-Mass Spectrometry

Efficient simultaneous photochemical vapor generation (PVG) of ruthenium (Ru) and osmium (Os) in the medium of formic acid was demonstrated. A flow-through photoreactor hyphenated to an inductively coupled plasma-mass spectrometer (ICP-MS) was used for the PVG and subsequent detection of the two elements. A similar synergistic enhancement from cobalt and cadmium ions on the PVG efficiency of both Ru and Os was discovered. Following the critical evaluation of the impacts of various transition metal ions, the concentrations of formic acid, cobalt, and cadmium ions, the flow rate of carrier gas, and the UV irradiation time, impressive limits of detection (LODs) of 5 and 0.5 ng L–1 were achieved for Ru and Os, respectively. The accuracy of the proposed PVG-ICP-MS method was validated by the analysis of several water samples with desirable spike recoveries obtained. Furthermore, the volatile compounds of Ru were directed and cryogenically trapped in acetonitrile and generation of carbonyls of Ru was verified by high-resolution electrospray ionization-mass spectra (ESI-MS).