Nuclear analytical methods for trace elements and their species

The main focus of my research lies in the fundamental development of nuclear analytical, bioanalytical and speciation methods for the determination of total as well as species-specific concentrations of elements of environmental and toxicological interest. We develop instrumental, preconcentration and radiochemical neutron activation analysis (NAA) methods for measuring total concentrations at the trace and ultra-trace levels of elements with high precision, accuracy, specificity, and rapidity using short- and medium-lived nuclides. We also develop special separation and purification methods for the characterization of various species of elements followed by their determination using NAA. Our proposed research program consists of six different projects. One of these projects involves the characterization of the Dalhousie University SLOWPOKE-2 reactor neutron flux and other parameters for the development of k0-NAA based methods. Another project is designed to evaluate the analytical advantages of anti-coincidence and coincidence-coincidence gamma-ray spectrometry for the detection of short- and medium-lived nuclides. A third project deals with the development of a method for the simultaneous preconcentration of metal chelates from aqueous samples by cloud point extraction using green chemistry. A combination of ion exchange, liquid chromatography, solvent extraction, and distillation methods in conjunction with NAA is the basis for the simultaneous determination of various species of arsenic, antimony and selenium in aqueous and marine samples. In another project, we are developing solvent extraction, gel filtration, liquid chromatography, reversed-phase extraction chromatography, and esterification coupled to NAA for the separation and characterization of potentially toxic extractable organohalogens in marine fish and mammals. We also investigate naturally occurring radioactive materials in drinking water and foods. We develop a number of analytical methods for studying various species of iodine in milk. Our research program provides training of undergraduate and graduate students, postdoctorates, and visiting scientists in nuclear analytical, environmental, nutritional and toxicological chemistry.