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Abstract: This work investigates the potential of high-resolution continuum source graphite furnace molecular absorption spectrometry for the direct determination of bromine in polymers, which could be interesting in view of the current regulations restricting the use of organobrominated compounds. The method developed is based on the addition of Ca (300μg) and Pd (30μg) to favor the formation of CaBr, which is monitored at the main molecular “lines” (rotational spectra) found in the vicinity of 625.315nm. It was found that accurate results could be obtained for all the samples investigated (polyethylene, polypropylene and acrylonitrile butadiene styrene certified reference materials) using any of the lines studied and constructing the calibration curve with aqueous standards. Furthermore, the combined use of the main four CaBr lines available in the spectral area simultaneously monitored permits to easily expand the linear range up to 2000ng, provides a limit of detection of 1.8ng (1.8μgg−1 for a mass of 1mg) and further improves precision to values between 3–7% RSD. Overall, the method proposed seems suited for the fast and simple control of these types of samples (approximately 10min for sample are required), circumventing the traditional problems associated with sample digestion (e.g., losses of volatile compounds), and providing sufficient sensitivity to easily comply with regulations. [Copyright &y& Elsevier]

Abstract: This work examines the capabilities and limitations of commercially available high-resolution continuum source atomic absorption spectrometry instrumentation for multi-line monitoring, discussing in detail the possible strategies to develop multi-element methodologies that are truly simultaneous, or else sequential, but from the same sample aliquot. Moreover, the simultaneous monitoring of various atomic or molecular lines may bring other important analytical advantages, such as: i) expansion of the linear range by monitoring multiplets; ii) improvements in the limit of detection and in precision by summing the signals from different lines of the same element or molecule; iii) simple correction for matrix-effects by selecting a suitable internal standard; or iv) accurate mathematical correction of spectral overlaps by simultaneous monitoring of free lines of the interfering molecule or element. This work discusses how authors have made use of these strategies to develop analytical methodologies that permit the straightforward analysis of complex samples. [Copyright &y& Elsevier]