Eleven repeat speciation analyses of Natural Water 1640 using LC-ICP-MS showed that the mean (SD) concentrations of [As.sup.III] and [As.sup.V] were 0.76 (0.05) [micro]g/L and 25.62 (0.61) [micro]g/L, respectively.
With the LC-ICP-MS method, the limits of detection, defined as the concentration of arsenic that produced a chromatographic peak having intensity equal to 3 times the SD of the baseline noise (30), were 0.03 g/L for [As.sup.III],[MMA.sup.III], and[DMA.sup.V]; 0.05 g/L for[MMA.sup.V]; 0.08 g/L for [As.sup.V]; and 0.1 g/L for [DMA.sup.III].
Results in Tables 1 and 2 show that the sum of arsenic species concentrations (obtained from LC-ICP-MS and LC-ESI-MS/MS) was in good agreement with the total arsenic concentrations (obtained from ICP-MS analyses without LC separation).
The detection and identification of trace arsenic species in saliva are possible because of the coupling of highly sensitive and selective analytical techniques (LC-ICP-MS and LC-ESI-MS/MS).
A few saliva samples showed detectable peaks matching those of [MMA.sup.III] and [DMA.sup.III] standards by LC-ICP-MS analysis; however, we were not able to provide confirmation by ESIMS/ MS analysis because of the limited sample volume and very low concentrations of these species.
Part 1: The mass spectrometer with inductively coupled plasma in conjunction with high performance liquid chromatography (LC-ICP-MS
)Module I: mass spectrometer with inductively coupled plasma in conjunction with liquid chromatographyModule II mass spectrometer with inductively coupled plasmaPart 2: A set of laser ablation,The spectrometer LIBS (Laser Induced Breakdown Spectroscopy) integrated with a 266 nm laser ablation (tandem)Part 3: Mineralizator microwaveMicrowave digestion with equipment.