A novel calibration strategy for the analysis of airborne particulate matter by direct solid sampling ETV-ICP-MS

Abstract

The use of polytetrafluoroethylene (PTFE) filter paper immersed in reference solutions is proposed as a novel external calibration strategy for the quantification of trace elements in fine particulate matter (PM2.5) by direct solid sampling–electrothermal vaporization–inductively coupled plasma-mass spectrometry (DSS-ETV-ICP-MS). This technique facilitated the simultaneous quantification of Mg, Mn, Cu, Zn, As, Sr, Cd, and Pb concentrations in PM2.5 samples collected on the PTFE filter paper. The feasibility of using this calibration method for DSS-ETV-ICP-MS was evaluated by studying physical samples collected in Hangzhou, China, and an NIST standard reference material (SRM) 1648a. The obtained results were in agreement with effective elemental concentrations (Dr <±10%), and exceptional reproducibility (RSDs less than 9%) and the linearity of the calibration curve (R2 > 0.997) under the limits of detection (LODs) at the µg L−1 level were achieved using elemental platinum as an internal standard. Therefore, this study suggests that using filter paper as the support in immersion standard solutions is a reliable method for calibration and PM2.5 trace elements quantification by DSS-ETV-ICP-MS.