Chemical trace element analysis is a many-faceted and important problem. Trace elements may be both toxic and essential to life. No longer is it sufficient to simply analyze for the total element amount, but we need additional information as to chemical form, oxidation state, organometallic nature, etc. Taken together this set of analyses is referred to as a “metallomics approach” involving total metal analysis plus speciation to characterize the different species of forms. Thus, there is a critical need to develop trace element analysis methods that allow separation of the different elemental species prior to trace element detection. In addition, we must analyze at environmental or biological concentration levels, often with sub-nanogram to picogram quantities. This challenging task requires state-of-the-art methods and instrumentation available in our labs.
Our group's research has been presented on the cover of several scientific journals
Separation Techniques for Speciation Studies: A separation technique interfaced to the element selective detector (such as inductively coupled plasma mass spectrometry, ICP-MS) provides a high degree of specificity for the methods we study. HPLC and GC are interfaced to ICP-MS for detection, allowing the separation and detection of a wide range of analytes. To assure our results or to resolve remaining unknowns, ESI-MS and MALDI-MS are used regularly.
Current Research Overview
- Exploring metalloproteins as putative biomarkers in cerebrospinal fluid for diagnosing and treating subarachnoid hemorrhage or its complication cerebral vasospasm.
- Investigation of metal-containing species in the human pathogen Histoplasma capsulatum to acquire more information about metal assimilation and toxicity mechanisms.
- Studying the cytotoxicity, phosphorylation and metallomics for the antagonism between As and Se in Human Kidney Cell 293.
- Method development utilizing the LC-ICPMS to specifically detect cross-links, to be applied to protein-RNA and protein-DNA cross-links via monitoring 31P and 32S.
- Removing inorganic phosphate via chemical precipitation for analysis of organophosphorus chemical warfare agent degradation products (CWADPs) with anion exchange HPLC for species separation and ICPMS for ultra trace detection of 31P.
- Examining protein phosphorylation changes and comparing the cytotoxicity in the memorialized HUV-EC-C human endothelial cell line and a keratinocyte primary culture with As+3 or Cr+6 alone or together and in combination as well as, SeMet as an antagonist.
- Investigating the toxic metals, VOCs, and PAHs in hookah tobacco, hookah charcoal, hookah alternative tobacco (steam stones), and e-cigarette products and their smoke via ICP-MS, HPLC, and SPME-GC-MS.