7^th World Congress on Mass Spectrometry June 20-22, 2018 Rome, Italy

R V Krishnamurthy obtained his PhD from the Physical Research Laboratory, Ahmedabad, India and worked as a Fellow of Geochemistry at the California Institute of Technology for seven years. In 1991, he moved to the Western Michigan University to set up a program in Stable Isotope Geochemistry. He is currently a Professor in the College of Arts and Sciences. He has published more than 60 papers in high impact journals such as Science, Nature, Geochimica et Cosmochemica Acta, Geophysical Research Letters, Applied Geochemistry, Geobiology and Scientific Reports. His research spans Biochemistry, Geochemistry, Hydrology, Atmospheric Sciences and Cosmochemistry. He is featured in Who’s Who in North American science.

Application of stable isotopes, especially carbon and nitrogen, are becoming a powerful tool in medical science. A novelapplication of the natural abundances of nitrogen isotopes, 14N and 15N in the understanding of amino acid metabolism inhuman colorectal cancer cells was carried out. Nitrogen isotope ratios are of particular advantage to understand the metabolic stateof cancer cells, since most biochemical reactions involve transfer of nitrogen. In this study nitrogen isotopes of individual amino acids from human colorectal cancer cell lines were analyzed. Significant effects were noticed in the case of glutamic acid, alanine,aspartic acid and proline between cancer and healthy cells. The data suggest that glutamic acid is a nitrogen acceptor while alanine,aspartic acid and proline are nitrogen donors in cancerous cells. One plausible explanation is the xtransamination of the three acids toproduce glutamic acid in cancerous cells. The findings are significant since glutamic acid and alanine make up more than 60 per centof the total amino acids in the human body. Glutamine is a significant source of energy for cells and also a prime donor of nitrogenin the biosynthesis of  amino acids. Several studies have advocated the role of glutamic acid incancer therapy. Identification ofmetabolic signatures in cancer cells will be crucial for advancement of cancer therapies based on the cell’s metabolic state.

Purushottam Chakraborty is a senior professor at Saha Institute of Nuclear Physics, Kolkata, India and an honorary professor at the University Of Pretoria, South Africa.His research interests range from ‘ion beam analysis of materials’ to ‘x-uv optics and photonics’. He worked at many renowned centres like FOM – Institute for Atomic andMolecular Physics, Padova University, ICTP, Laval University, Osaka Electro-communication University, etc. He has published more than 125 papers including reviews and book-chapters. He has been awarded the ‘most eminent mass spectrometrist of India’ and is one of the world leaders in Secondary Ion Mass Spectrometry (SIMS).

If alkali metals such as Cs, Li, Rb, K, Na, etc. (referred as A in general) are present in the neighborhood of the probing element(M) on a sample surface, quasi-molecular ions can be formed by the attachment of these alkali ions [(MA)+ formation] in thesecondary ion mass spectrometry (SIMS) process. Formation of these MA+ molecular ions has astrong correlation to the atomicpolarizability of the element M. The emission process for the re-sputtered species M0 is decoupled from the MA+ ion formationprocess, in analogy with the ion formation in secondary neutral mass spectrometry (SNMS), resulting in a drastic decrease in the conventional ‘matrix effect’ in SIMS. Although the detection of MA+ molecular ions in SIMS has found its applicability in directmaterials quantification, it generally suffers from a low useful yield. In such cases, detection of (MA)n+ (n=2, 3,….) molecular ionsoffers a much better sensitivity (even by several orders of magnitude), as the yields of such molecular ion complexes have oftenbeen found to be higher than that of MA+ ions. The recombination coefficient of MA+ or MA2+ molecular species depends onthe electro-positivity or electro-negativity of the element M, respectively. Apart from the surfacebinding energy of the respectiveuppermost monolayer, the changes in local surface work-function have often been found to play a significant role in the emissionof these molecular ions. Although these MAn+ molecular-ion based SIMS has great relevance in the analysis of materials, acomplete understanding on the formation mechanisms of these ion-complexes is still lacking. A procedure, based on MAn+-SIMSapproach, has been proposed for the accurate germanium quantification in molecular beam epitaxy (MBE)-grown Si1−xGex alloys.The ‘matrix effect’ has been shown to be completely suppressed for all Ge concentrationsirrespective of impact Cs+ ion energies.Cesium, the fifth alkali element, is the most reactive of all the metals. The methodology hassuccessfully been applied for directquantitative composition analysis of various thin film and multilayer structures. Recent study on various ZnO-based nanostructures has successfully been correlated to their photo-catalysis and photoemission responses. The present talk will address the complex formation mechanisms of MAn+ molecular ions and potential applications of the MA+-SIMS approach in chemical analysis of low dimensionalmaterials and nanostructures.

Steven J Soldin has obtained his PhD in Biochemistry at the University of the Witwatersrand in Johannesburg, SA. After a Postdoctoral year at the University of Torontohe enrolled in a Clinical Biochemistry program at that University, obtained his Diploma in Clinical Biochemistry and was boarded in this discipline in both Canada and theUSA. He has been a tenured Professor at both the University of Toronto and the George Washington University School of Medicine. He is currently Senior Scientist in the Department of Laboratory Medicine at the National Institutes of Health, Bethesda, USA. He has published 275 papers in peer reviewed journals and has many patents.

This talk will focus on how mass spectrometry improves both diagnosis and treatment of patients with hypothyroidism (20million in the USA). We will discuss current problems with immunoassays for thyroid testing which frequently lead to thewrong diagnosis and poor patient management. In contrast the diagnosis of hypothyroidism is more reliable utilizing UF LCMS/MS (ultra-filtration tandem mass spectrometry) for the measurement of FT4, FT3, TT3 and TT4. The suboptimal current role ofthe FDA in licensing inaccurate and unreliable immunoassay methods and the approaches of the AACC and IFCC to harmonizeimmunoassay platforms with reference LCMS/MS methods will be critiqued. Finally evidence of poor performance of thyroidstimulating hormone (TSH) tests in predicting thyroid disease will be discussed.