Overcoming ICP-QMS instrumental limitations for 99Tc determination in environmental solid samples using radiochemistry

A comparison study on the use of Dowex 1 and TEVA-resin in determination of 99Tc in environmental and nuclear coolant samples in a SIA system with ICP-MS detection

This work refers to a comparative study of sorbents widely used in determinations of ⁹⁹Tc such as TEVA resin and Dowex 1. Despite having a similar functional group of quaternary amines, both materials represent different chromatographic methods-extraction (TEVA resin) and anion exchange (Dowex 1)-which provides a diverse range of their properties significant in determination of ⁹⁹Tc in flow conditions. The comparative tests, carried out in a SIA-LOV (Sequential Injection Analysis-Lab-on-Valve) system combined with mass spectrometric (ICP-MS) detection, considered several factors that are crucial from the standpoint of resin´s utility such as sorption capacity, durability, or selectivity, critical in ⁹⁹Tc separation from interferences. The developed and optimized analytical procedure based on the application of the TEVA resin provided determinations of ⁹⁹Tc at minimum detectable limit (MDL) 6.00 mBq L^-1 in 50 min and has been successfully employed in analyses of samples from nuclear industrial and research units (reactor coolant and sewage) as well as from the river surrounding the nuclear reactor. The method proved to be sufficient for routine analysis of water samples in accordance with EPA standards. The reliability of the method was confirmed in the analysis of the BH standard provided by the NPL for inter-laboratory proficiency tests. The ⁹⁹Tc recovery for all real samples was evaluated as 80-100%.

Automatic in-syringe dispersive liquid-liquid microextraction of ⁹⁹Tc from biological samples and hospital residues prior to liquid scintillation counting

A new approach exploiting in-syringe dispersive liquid-liquid microextraction (DLLME) for (99)Tc extraction and preconcentration from biological samples, i.e., urine and saliva, and liquid residues from treated patients is presented. (99)Tc is a beta emitter with a long half-life (2.111 × 10(5) years) and mobility in the different environmental compartments. One of the sources of this radionuclide is through the use of its father (99m)Tc in medical diagnosis. For the first time a critical comparison between extractants and disperser solvents for (99)Tc DLLME is presented, e.g., tributyl phosphate (TBP), trioctylmethylammonium chloride (Aliquat®336), triisooctylamine (TiOA), as extractants in apolar solvents such as xylene and dodecane, and disperser solvents such as acetone, acetonitrile, ethanol, methanol, 1-propanol, and 2-propanol. The system was optimized by experimental design, and 22.5% of Aliquat®336 in acetone was selected as extractant and disperser, respectively. Off-line detection was performed using a liquid scintillation counter. The present method has a (99)Tc minimum detectable activity (MDA) of 0.075 Bq with a high extraction/preconcentration frequency (8 h(-1)). Urine, saliva, and hospital residues were satisfactorily analyzed with recoveries of 82-119%. Thus, the proposed system is an automatic powerful tool to monitor the entry of (99)Tc into the environment. Graphical Abstract (99m)Tc is widely used in Nuclear Medicine for diagnosis. Its daugther (99)Tc is automatically monitored in biological samples from treated patients by in-syringe dispersive liquid-liquid microextraction.

Determination of technetium-99 in environmental samples: a review

Due to the lack of a stable technetium isotope, and the high mobility and long half-life, (99)Tc is considered to be one of the most important radionuclides in safety assessment of environmental radioactivity as well as nuclear waste management. (99)Tc is also an important tracer for oceanographic research due to the high technetium solubility in seawater as TcO(4)(-). A number of analytical methods, using chemical separation combined with radiometric and mass spectrometric measurement techniques, have been developed over the past decades for determination of (99)Tc in different environmental samples. This article summarizes and compares recently reported chemical separation procedures and measurement methods for determination of (99)Tc. Due to the extremely low concentration of (99)Tc in environmental samples, the sample preparation, pre-concentration, chemical separation and purification for removal of the interferences for detection of (99)Tc are the most important issues governing the accurate determination of (99)Tc. These aspects are discussed in detail in this article. Meanwhile, the different measurement techniques for (99)Tc are also compared with respect to advantages and drawbacks. Novel automated analytical methods for rapid determination of (99)Tc using solid extraction or ion exchange chromatography for separation of (99)Tc, employing flow injection or sequential injection approaches are also discussed.

Current literature in mass spectrometry

In order to keep subscribers up‐to‐date with the latest developments in their field, John Wiley & Sons are providing a current awareness service in each issue of the journal. The bibliography contains newly published material in the field of mass spectrometry. Each bibliography is divided into 11 sections: 1 Books, Reviews & Symposia; 2 Instrumental Techniques & Methods; 3 Gas Phase Ion Chemistry; 4 Biology/Biochemistry: Amino Acids, Peptides & Proteins; Carbohydrates; Lipids; Nucleic Acids; 5 Pharmacology/Toxicology; 6 Natural Products; 7 Analysis of Organic Compounds; 8 Analysis of Inorganics/Organometallics; 9 Surface Analysis; 10 Environmental Analysis; 11 Elemental Analysis. Within each section, articles are listed in alphabetical order with respect to author (6 Weeks journals ‐ Search completed at 4th. Oct. 2006)