Graduate student Nuwan Kothalawala will present his dissertation research “Method development for mass spectrometric characterization of ultra-small nanomolecules and mass spectrometry imaging of biomolecules” to the department.
High sensitivity, good selectivity and remarkable identification capability facilitates the application of mass spectrometry (MS) in diverse fields. This talk outlines how this cutting edge technology is used to determine the chemical composition of the ultra-small nanomolecules (NMs) to atomic precision and obtain spatial resolution of selected biomolecules using mass spectrometric imaging (MSI). High resolution electrospray ionization mass spectrometry (ESI-MS) methods were developed to analyze the polar water-soluble NMs. These new methodologies express how ESI-MS parameters can be optimized to analyze the NMs based on their polarity, chain-length of the ligands, size and stability. In addition, new methods are presented on how to overcome common issues such as impurities in analytes, adduct formation and solvent clusters arising during the analysis of polar NMs. These also include the special approaches to enhance the peak intensities and lower the fragmentations. Further, new protocols are discussed to synthesize, separate and purify NMs in an unprecedented range from 100’s to 1000’s of atoms. Matrix assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) methods were developed to study biologically important molecules and their spatial location in different samples such as microbial colonies, animal tissues, plant tissues and forensic samples. The microbial species produce important natural products and metabolites. This talk has two themes based on method development for MSI to detect the important secondary metabolites including rapamycin and manzamine in bacteria colonies. After the discovery of standard imaging methods, MSI projects were further extended to image the important analytes in forensic samples, animal and plant tissues.
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(2) Kothalawala, N.; Lee West Iv, J.; Dass, A. Nanoscale 2014, 6, 683.
(3) Waters, A. L.; Peraud, O.; Kasanah, N.; Sims, J.; Kothalawala, N.; Anderson, M. A.; Abbas, S. H.; Rao, K. V.; Jupally, V. R.; Kelly, M.; Dass, A.; Hill, R. T.; Hamann, M. T. Frontiers in Marine Science 2014, 1.
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