Development of an Automatic Method for Americium and Plutonium Separation and Preconcentration Using an Multisyringe Flow Injection Analysis-Multipumping Flow System

Development of an Automatic Column Chromatography Separation Device for Metal Isotope Analysis Based on Droplet Counting

A novel, simple, cost-effective, reliable, and practical automatic column chromatography separation device capable of simultaneously purifying samples for radiogenic and non-traditional stable isotope analysis has been developed. The device avoids the use of any pump and features eluent driving by the siphon effect (gravity) and quantitative control by infrared droplet counting. Several factors affecting the control of droplets were investigated, including types and concentrations of eluents and the height of the liquid level. Results showed that accurate dripping of the eluent could be readily achieved by controlling the number of droplets under selected conditions. The separation performance of the device was first demonstrated by the elution of Sr and Cd in synthetic matrix solutions. The recoveries of Sr and Cd samples were better than 87.6 and 95.0%, respectively, and the whole procedure blank was about 0.3 ng for Sr and 0.1 ng for Cd. Finally, the reliability of the device was further validated by the purification of Sr and Cd from different geological reference materials (NIST 2711a, Nod-A-1, BCR-2, and BHVO-2). The determined Cd and Sr isotope values agree well with their reference values within the uncertainty range. All these results clearly demonstrate the reliability and practicability of the proposed device, which provides a promising method for the automated purification of isotope samples.

Dynamic Flow Approaches for Automated Radiochemical Analysis in Environmental, Nuclear and Medical Applications

Automated sample processing techniques are desirable in radiochemical analysis for environmental radioactivity monitoring, nuclear emergency preparedness, nuclear waste characterization and management during operation and decommissioning of nuclear facilities, as well as medical isotope production, to achieve fast and cost-effective analysis. Dynamic flow based approaches including flow injection (FI), sequential injection (SI), multi-commuted flow injection (MCFI), multi-syringe flow injection (MSFI), multi-pumping flow system (MPFS), lab-on-valve (LOV) and lab-in-syringe (LIS) techniques have been developed and applied to meet the analytical criteria under different situations. Herein an overall review and discussion on these techniques and methodologies developed for radiochemical separation and measurement of various radionuclides is presented. Different designs of flow systems with combinations of radiochemical separation techniques, such as liquid-liquid extraction (LLE), liquid-liquid microextraction (LLME), solid phase extraction chromatography (SPEC), ion exchange chromatography (IEC), electrochemically modulated separations (EMS), capillary electrophoresis (CE), molecularly imprinted polymer (MIP) separation and online sensing and detection systems, are summarized and reviewed systematically.

An Overview of Analytical Methods for in Vitro Bioassay of Actinides

The bioassay of urine and fecal samples has been used since the 1940s to determine an individual's uptake of uranium and actinide elements such as americium and plutonium. Over the years, several analytical separation methods and techniques have been employed for these types of analyses. Analytical separations, ranging from solvent extraction and anion exchange to chromatography, and analytical techniques, ranging from autoradiography to kinetic phosphorescence to fission-track analysis and high-resolution solid-state alpha spectroscopy, have been used at one time or another. Over the last few decades, there have been significant advances in radiochemical separations, as well as an increased use of mass spectroscopy, to determine trace and ultratrace levels of actinides in urine and fecal samples. This review summarizes and discusses developments in radiochemical separation methods and advancements in analytical techniques for actinide bioassay since the early 1940s to the present, followed by a recent development and trend in the bioassay of actinides-particularly in urine and fecal samples.

Laboratory automation based on flow techniques

Flow techniques have undoubtedly aroused special interest in relation to many other automatic methodologies of analysis. Ever since segmented flow analysis (SFA) was developed by Skeggs in 1957, flow techniques have been in continuous evolution toward new develop-ments. There is no solid argument in favor of using any particular flow technique separately; rather, substantial advantages can be derived from their combination. Since flow-based methods are nonseparative tools, the advantages of combining flow techniques with separation techniques are noteworthy. High selectivity can be achieved by coupling them with liquid chromatography (LC), gas chromatography (GC), solid-phase extraction (SPE), or capillary electrophoresis (CE). Thus, a detailed description of flow techniques, their evolution, their hyphenation advantages, and a critical comparison between current developed methods exploiting flow techniques aimed at solving present analytical needs are reviewed in this article.