Preparation techniques, radionuclides

Sample preparation techniques involve the chemical separation of the specific chemical forms of a radionuclide, and the preparation of the counting sample by mixing the separated nuclides with the proper liquid scintillator. 

An alternative electrochemical source separation and preparation technique is electrophoresis. A drop of the radionuclide solution is pipetted at one end of a moistened paper strip that has an electric potential difference along its length. Each ionic radionuclide moves at its own rate down the strip. Locations of individual radionuclides are identified by their radiation or by dyes affected by the chemical form (Deyl 1979). 

Methods of incorporating inorganic radiochemicals into liquid and solgel scintillators that exhibit high scintillation yield are described. Liquid-scintillation measurements have been made at the National Bureau of Standards on 31 different radionuclides for a variety of application in radionuclide metrology. Sample preparation techniques are described for a number of radionuclides that differ markedly in their chemical behavior as well as in their nuclear-decay characteristics. Particular emphasis is given to radionuclides such as Fe and... 

The combination of 1.1. with chromatographic and histochemical or cytochemical techniques represents a powerful experimental technique known as autoradiography. When X-ray film is laid directly over a preparation containing radionuclides, their positions are indicated by darkening of the film. The technique... 

Analytical applications of radionuclide techniques rely on the assumption that different isotopes of the same element exhibit the same properties in any macroscopic physical or chemical process, and that radioactive labeling does not influence the other properties of a chemical species. This is generally the case, with deviations below 1 % (with the exception of hydrogen isotopes) owing to isotopic fractionation or radiation effects. For analytical purposes, the radiotracer and the analyte mu.st be present in the same chemical form. This is usually to achieve, but specialized preparative techniques may be necessary for radioactive labeling of more complex organic compounds. 

The fc0-NAA method has been developed to overcome the labour-intensive and time-consuming work of preparing multi-element standards when routine multielement or panoramic analyses are required [447]. It is intended to be an absolute technique in which uncertain nuclear data are replaced by a composite nuclear constant, the T 0-factor, which has been determined experimentally for each radionuclide with high accuracy. This k0 is given by ... 

Modem techniques of preparation, refining and crystal growth have been adapted to the special precautions for handling radionuclides. 

This laboratory experiment describes the preparation of a vegetation sample (e.g., grass) for radiochemical analysis. The sample is dried and ashed. In Part 12A, the ash is fused with sodium hydroxide and sodium carbonate to bring it into solution. An alternative method in Part 12B uses a microwave-assisted digestion technique with nitric and hydrofluoric acid. The prepared sample is suitable for radionuclide analysis, notably for radio-strontium or plutonium. 

The present studies were aimed at the development of laboratory evaluation techniques for studying the efficacy of therapeutic radiopharmaceuticals. The primary goal was to develop radiotherapeutic agents using the peptide-BFCA conjugate DOTA-Tyr -octreotate (DOTATATE). The radioisotopes used for the therapeutic preparations were Lu and °Y. Lutetium-177 was identified as an ideal radionuclide for... 

Sterile products of short half-life radionuclides are commonly prepared by aseptic technique at or near the place of use from previously prepared components ( kits ), and the eiuate of a radionuclide generator. It may be acceptable to carry out this work under environmental conditions of a lower grade than those described for aseptic work in Section 9 when the following situation pertains ... 

The success of an irradiation experiment depends to a large extent on the target considerations. In many nuclear experiments as much time has to be devoted to the target preparation as to the rest of the experiment. If the purpose is to produce a radionuclide for a simple tracer experiment, the consideration in this section may be sufficirait. If, however, the requirements are a product of extreme purity, very high specific activity, or very short half-life, special techniques must be used, which are discussed in 15.5-15.7. 

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