NMR spectroscopy based evaluation of urine for identification of changes in functional metabolites on exposure to Thallium- 201 in mice

Introduction: Thallium-201 (Tl-201) is routinely administered to people undergoing nuclear medicine scans at activity levels of 3-5 milli curies (mCi). Due to its short halflife, relatively low hazard radiations and rapid biological excretion, thallium-201 has very low radio toxicity when introduced internally. However, the recommended dose of Tl-201 is considered clinical safe and gets excreted from body with in 24-48 hrs of its injection. Physiologically, after injection, it behaves as a potassium analog and gets accumulated rapidly in the cells of many organs, which may lead to some alterations at metabolite levels. NMR Spectroscopy allows the detection of a wide range of structurally diverse metabolites simultaneously, providing a metabolic ‘snapshot’ at a particular time point. Urine in comparison with other biofluids, has relatively low concentrations of proteins and high concentrations of low molecular-weight compounds thus minimizing sample preparation and result in high-quality measurements due to the narrow line widths of the spectral peaks. Therefore, it was proposed to study the metabolic profiles of urine samples obtained from Tl-201 treated mice and look upon the changes at metabolite levels if any using NMR spectroscopy.