High-Resolution Mass Spectrometry as a Tool To Evaluate the Sample Preparation of Sludge

This study explored the sample preparation steps based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) of a complex matrix, such as sewage sludge, regarding their impacts on the chemical signatures of the samples obtained via high-resolution mass spectrometry (HRMS). The effects on the HRMS signal of the intrinsic parameters of the QuEChERS method, such as the extraction solvent, the buffer salt, or the purification procedure, have been evaluated. Different strategies have been used to perform these evaluations, such as a comparison of the total number of HRMS signals, a comparison of the targeted screening based on more than 100 compounds, and a comparison of a nontargeted screening based both on the study of the most discriminating couples [mass-to-charge ratio (m/z); retention time (tR)] and on the most intense peaks. Moreover, two specific methods dedicated to the extraction of surfactants and drugs have been added to this comparison to visualize the impact of specific conditions on the ...