A technique is described involving simultaneous, dual-isotope SPECT imaging. Using 123I and 201TI, a patient study is presented, demonstrating the clinical utility of this technique in the detection and characterization of parathyroid pathology. The use of this technique in other clinical situations is discussed.

Metal isotope coded profiling (MICP) introduces a universal discovery platform for metal chelating natural products that act as metallophores, ion buffers or sequestering agents. The detection of cation and oxoanion complexing ligands is facilitated by the identification of unique isotopic signatures created by the application of isotopically pure metals.

BACKGROUND Isotope-dilution assays (IDAs) are well established for quantification of metabolites or small drug molecules in biological fluids. Because of their increased specificity, IDAs are an alternative to immunoassays for measuring C-peptide. METHODS We evaluated a 2-dimensional liquid chromatography-mass spectrometry (2D LC/MS) IDA method. Sample preparation was by off-line solid-phase ...

Environmental monitoring of actinides and evaluation of the contamination source (nuclear weapons tests, nuclear power plant and nuclear reprocessing plant accidents, etc.) requires precise and accurate isotopic analysis of actinides, especially uranium and plutonium. Double-focusing sector-field inductively coupled plasma mass spectrometry (ICP-SFMS) using a low-flow microconcentric nebulizer ...

cosmic rays in the upper troposphere (9000 meters to 15000 meters) initiate the followingnuclear chemical reaction: 1n + 14n => 14c + 1h. previous research has shown a strong effect of latitude onthe abundance of neutrons from cosmic rays. however, to date, there has been little exploration of therelationship between the latitude effect for cosmic-ray neutrons and latitudinal variations of stab...

While the quantification of uranium is therefore demanding in the diluted sample, uranium isotope ratio determination requires the ultimate in instrumental performance as good precisions for large isotope ratios are required at low concentrations. The abundances of the three naturally occurring U isotopes are shown in Table 1, together with the 234U/238U and 235U/238U ratios. The nuclear indust...

As an approach to delivery of inert gas to the myocardium in the presence of coronary artery obstruction, Kr in saline was injected into a catheter in the coronary venous system of intact anesthetized dogs. Isotope delivered at the level of the great cardiac vein was selectively localized in the region of myocardium subserved by the vein and the left anterior descending artery. Similarly, injec...

A method for the measurement of uric acid in human serum by isotope dilution-mass spectrometry is described. The analytical procedure consists of the following steps: Addition of [1,3-15N2]uric acid to the serum sample; ion exchange chromatography on AG1-X2; formation of the trimethylsilyl derivative; gas liquid chromatography-mass spectrometry (GC-MS), selected ion monitoring (SIM) at m/z-valu...

Electrothermal vaporization isotope dilution inductively coupled plasma mass spectrometry (ETV-ID-ICP-MS) was applied to the determination of Cd and Pb in urine samples. The isotope ratios for each element in each analytical run were calculated from the peak areas of each isotope. A relatively low vaporization temperature was used, which separated the analyte from the major matrix components an...