Forensic investigation of brick stones using instrumental neutron activation analysis (INAA), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and X-ray fluorescence analysis (XRF).
Abstract Brick stones collected from different production facilities were studied for their elemental compositions under forensic aspects using laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS), instrumental neutron activation analysis (INAA) and X-ray fluorescence analysis (XRF). The aim of these examinations was to assess the potential of these methods in forensic comparison analyses of brick stones. The accuracy of the analysis methods was evaluated using NIST standard reference materials (679, 98b and 97b). In order to compare the stones to each other, multivariate data analysis was used. The evaluation of the INAA results (based on the concentrations of V, Na, K, …
Calibration of LA-ICP-MS via standard addition using dried picoliter droplets
A novel microanalytical calibration approach for quantitative spatially resolved analysis of thin layered materials with laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is presented. This method relies on standard addition via the generation of dried pL-droplet residues. Therefore, a drop on demand dosing device based on a modified commercial ink cartridge and a dosing interface, both accessible via a self-constructed microcontroller, were developed. This dosing device enables the precise deposition of pL-droplets onto solid samples for the generation of residues with dimensions in the low μm-range. The LA-ICP-MS analysis of such residues allows calibration over at l…
Forensic comparison of PVC tape backings using time resolved LA-ICP-MS analysis
Abstract Adhesive tapes are common tools for criminal acts such as the construction of improvised explosive devices. Hence, tape samples can be used as evidence to link a suspect to a scene of crime or different crime scenes to each other. A set of 87 black electrical tapes was the subject of a study evaluating a LA-ICP-MS method for the characterization of tape backings regarding their elemental composition in a forensic context. LA-ICP-MS is a powerful tool in forensic investigations due to fast, quasi nondestructive analysis of small samples and detection or determination of elements up to the ultra-trace range. In this study, the development of a semiquantitative LA-ICP-MS method for fo…