Detection of single-walled carbon nanotubes in environmental samples by Field flow fractionation - NIR fluorescence spectroscopy
Monday, February 21, 2011
Ariette Schierze, Ph.D.
Civil and Environmental Engineering
Abstract: Single-walled carbon nanotubes (SWNT) are considered as a new class of emerging environmental pollutants. Investigations of fate and toxicity of SWNT in the environment are limited by the lack of reliable methods to detect these materials in complex mixtures at environmentally-relevant concentrations. In this study the combination of field flow fractionation (FFF) with NIR-fluorescence spectroscopy is evaluated for determination of SWNT in environmental samples. NIRF spectroscopy is a sensitive method to detect SWNT in complex samples after extraction (DL lower ng ml-1 range) as well as gain structural information such as chiral wrapping angle of SWNT. Utilizing “time-resolved” FFF-NIRF spectroscopy compared to static NIRF spectroscopy enabled the detection of extracted from SWNT-spiked natural sediment [> 1 ug/g sediment] in lower concentrations. These results reveal FFF can be used successfully as clean-up tool prior to NIRF analysis to reduce matrix complexity by separation of NOM and SWNT.