Radiochemistry automation

Figure 8.3. A schematic block diagram showing different components in the 18F-FDG synthesis box. (Reproduced with kind permission of Kluwer Academic Publishers from Crouzel C et al (1993) Radiochemistry automation PET. In Stocklin G, Pike VW (eds) Radiopharmaceuticals for positron emission tomography, Kluwer Academic, Dordrecht, The Netherlands, p 64. Fig. 9)...

Fluidic approaches move samples, reagents, and eluents from place to place entirely through a system of pumps, valves, and tubing. Fluidic methodology from the field of flow injection (FI) analysis has been adapted to the needs of automated radiochemistry. In its original form, FI used a multichannel peristaltic pump and an injection valve in a continuous forward flow paradigm to mix the sample with reagents and... 

Grate, J. W. and Egorov, O. B., Automating analytical separations in radiochemistry, Anal. Chem., 70, 779A-788A, 1998. 

Synthesis of labelled compounds requires reliable procedures and experience in radiochemistry. However, special kits are available for preparation of labelled compounds without experience in radiochemistry, and automated procedures have been developed for fast syntheses. 

The concept of employing reaction-rate parameters to determine the initial analytical concentration of reactants dates back over 50 to 60 years to the early literature in biochemistry, radiochemistry, and gas-phase diffusion furthermore, among all the analyses performed in all the laboratories around this country, the number carried out by kinetic-based methods probably exceeds that carried out by thermodynamic methods and direct instrumental measurement combined. This comes as a surprise at first, until one considers the large numbers of enzymatic and other determinations done on multi-channel autoanalyzers used in clinical laboratories. Most of these rapid automated instruments use kinetic methods. 

The last three chapters consider special aspects of radioanalytical chemistry that have become increasingly important and visible. Chapter 15 describes the automated systems that are used to measure radionuclides in the counting room and in the environment. Chapter 16 is devoted to identification and measurement of the radionuclides beyond the actinides. These are research projects at the cutting edge of radiochemistry that apply novel rapid separations in order to measure a few radioactive atoms before they decay. Much must be inferred from limited observations. In Chapter 17, several versions of mass spectrometers combined with sample preparation devices are described. The mass spectrometer, applied in the past as a research tool to detect a small number of radioactive atoms per sample, is now so improved that it serves as a reliable alternative to radiation detection for radionuclides with half-lives as short as a few thousand years. 

There is another problem with man-made chemical elements, namely that their isotopes are short lived too. This, together with the need for their identification, calls for fast separation methods. The Automated Rapid Chemistry Apparatus (ARCA) II S) tem and the Short-lived Isotopes Studied by the AKUFVE-technique (SISAK) equipment (both described in Sect. 59.2.2 of Chap. 59, Vol. 6, on Solvent Extraction and Ion Exchange in Radiochemistry ) are able to handle radionuclides with half-lives of -10 s and 1 s, respectively. 

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