Allan Philippe
Koblenz-Landau University, Germany
Title: Hydrodynamic chromatography coupled to ICP-MS for studying nanoparticles in complex media
Biography
Biography: Allan Philippe
Abstract
Investigation of colloids behaviour in the environement are highly challenging due to the lack of robust and efficient methods for sizing and quantifying engineered or natural colloids in environmental media. Hydrodynamic chromatography (HDC) coupled with ICP-MS is a practical and efficient technique for the detection of inorganic nanoparticles in complex media. The claimed advantages of the method are its versatility, its relative simplicity, high recoveries, and the possibility to combine sizing and quantitative analysis. Despite ist long history, HDC validation for environmental samples and complex particles has been investigated only recently. Especially, the effect of particle shape on the retention factor remained unaddressed, although most natural colloids are non-spherical. The recent development of single particle ICP-MS (SP-ICP-MS) made possible to use this technique in combination with HDC with a powerful synergy. This presentation reports and discusses our advances in the development of HDC-SP-ICP-MS to analyse metal containing nanoparticles (e.g. Au, Ag, TiO2, CeO2) in complex media. Using standard equipment and well characterized calibrants with different densities and coatings, we demonstrated the universality of the size calibration method for HDC-ICP-MS. Several applications of this technique to complex media demonstrate its versatility. Based on measurements of standard particles having different shapes, we propose a method to differentiate between spherical and non-spherical, including fractal agglomerates, using HDC-SP-ICP-MS. Powerful combination of detectors, versatility, and possibility to size and quantify inorganic colloids simultaneously in complex matrixes are strong arguments for a wide application of HDC in colloids analysis in environmental sciences.