INDUCTIVELY COUPLED PLASMA MASS-SPECTROMETRY AS AN ELEMENT-SPECIFIC DETECTOR FOR FIELD-FLOW FRACTIONATION PARTICLE SEPARATION

An inductively coupled plasma-mass spectrometer was used for the quantitative measurement of trace elements in specific, submicrometer size-fraction particulates, separated by sedimentation field-flow fractionation. Fractions were collected from the eluent of the field-flow fractionation centrifuge and nebulized, with a Babington-type pneumatic nebulizer, into an argon inductively coupled plasma-mass spectrometer. Measured ion currents were used to quantify the major, minor, and trace element composition of the size-separated colloidal (< 1-mu-m diameter) particulates. The composition of surface-water suspended matter collected from the Yarra and Darling rivers in Australia is presented to illustrate the usefulness of this tool for characterizing environmental materials. An adsorption experiment was performed using cadmium ion to demonstrate the utility for studying the processes of trace metal-suspended sediment interactions and contaminant transport in natural aquatic systems.