Simultaneous detection of trace As, Hg, Tl, and Pb in biological tissues using monochromatic excitation X-ray fluorescence spectrometry

Monochromatic excitation X-ray fluorescence (ME-XRF) spectrometry is an emerging technique for elemental analysis with many potential forensic applications. In this study, a method for rapid and efficient quantification of As, Hg, Tl, and Pb in biological tissues using ME-XRF was established and applied to actual cases. The instrument's operating conditions were optimized, and the optimum method for sample preparation was determined. According to the calibration curves of each element, a new model for the detection of biological tissues was developed based on the fundamental parameter (FP) method. The LOD values of As, Hg, Tl, and Pb were 0.04, 0.04, 0.06, and 0.07 μg g−1, respectively. Through systematic evaluation and validation, the feasibility of using ME-XRF in forensic toxicology analysis was confirmed.