New slurry autosampler for direct analysis of environmental samples via graphite furnace atomic absorption spectrometry
Source: BAM
Graphite furnace atomic absorption spectrometry (GF-AAS) is a powerful technique for analysing trace elements and offers high sensitivity and precision. However, its performance is limited by sample preparation for solid samples such as soils and plastics. Conventional sample preparation usually involves digestion, which is time-consuming and requires reagents such as acids, contributing to measurement uncertainty and causing a higher carbon footprint. Therefore, analysing solid samples directly as a slurry, i.e. as a solid suspended in a liquid, offers many advantages. However, maintaining suspension stability is a major challenge. We have therefore developed a new type of autosampler that enables slurries to be analysed easily via GF-AAS. The system ensures the stability of the suspension by means of an agitator and closed vessels to prevent evaporation and contamination. Furthermore, the system contains a cooling unit to reduce solvent and analyte losses. It can be installed and removed from the GF-AAS device in minutes. The system was validated using the two certified reference materials BAM-U110 (contaminated soil) and BAM-H010 (ABS plastic). A recovery rate of 94 % ± 13 % was achieved for cadmium in BAM-U110. For BAM-H010, the recovery rate was 104 % ± 11 %.
The new system helps to solve key problems in the trace element analysis of solid samples and makes the process faster and more accurate. It also works with complex materials and is therefore also suitable for other areas such as analysing microplastics or nanoparticles. As a flexible tool for high-throughput analyses, it will make an important contribution to the monitoring of environmental and polymer samples in the field of regulation in the future.
Development of a fully automated slurry sampling introduction system for GF-AAS and its application for the determination of cadmium in different matrices
Charlie Tobias, Lennart Gehrenkemper, Thomas Bernstein, Sven Schlau, Fabian Simon, Mathias Röllig, Björn Meermann, Marcus von der Au a d
Analytica Chimica Acta, Volume 1335, 15 January 2025