In time-resolved and size-segregated elemental analysis of airborne PM, TXRF demonstrates superior performance compared to the conventional ICP-MS approach for samples collected on cascade impactors at high frequency. In this context, a significant challenge is to achieve traceability due to the variability in aerosol deposition patterns on impaction plates, necessitating reference samples that accurately mimic these deposits in both spatial distribution and elemental composition . A comprehensive review summarizes the sample preparation methods used for qualitative and quantitative analysis of PM filters by TXRF . In the pursuit of optimizing sample preparation techniques, Wagner et al. in 2010 demonstrated the superiority of cold plasma ashing over conventional digestion methods for aerosol particles collected on polycarbonate filters, particularly in terms of streamlined sample preparation and reduced contamination risks. However, it's worth noting that additives, such as the fixatives employed to affix the filter material onto TXRF sample carriers, warrant further investigation to identify and mitigate potential sources of contamination. The thin film like correlation between XRF intensity and elemental concentration is clearly demonstrated when analysing atmospheric PM filters prepared with SMART STORE® measured in TXRF instruments with strong evidence of the possibility to realize matrix calibration curves . This correlation forms the basis for conducting quantitative elemental analysis of PM filters, provided that appropriate calibration samples are available to validate the analytical method. The calibration samples enable the determination of a linear calibration range, as well as the establishment of limits of detection and limits of quantification. These parameters are crucial in ensuring accurate and reliable quantification of elements in PM filters . The application of reference PTFE filters measured by XRF under grazing incidence (GI) conditions demonstrated a linear range from 0.028 to 4.239 μg cm -2 , and the RSDs were below 10%, revealing a promising and precise results for Pb concentrations . This determination was made through rigorous statistical analysis, including a comparison with a quadratic regression model. It's worth noting that the linear range's upper limit was capped to exclude the highest lead loading sample where absorption effects were not compensated, ensuring the accuracy and reliability of the linear relationship within this specified concentration range. Moreover, the Smart Store® procedure demonstrated to be versatile to be applied for many fluorescence based techniques: µ-XRF, EDXRF, TXRF and GIXRF, and synchrotron radiation (SR) . Data obtained by SR-XRF showed that the instrumental configuration has a significant impact on the results. The more focused the beam, the more visible the inhomogeneity. Inhomogeneity clearly increases with mass deposition . All the studies reviewed in the literature consistently highlight the numerous advantages of TXRF over ICP-MS in terms of sample preparation, analysis, and data outcomes. TXRF presents a streamlined and more straightforward sample preparation process, in addition to the simplicity of instrument use and maintenance, not requiring routine calibration, vacuum pumps and gasses.