Radiochemical analysis classic

The analysis of iodine at trace levels is reviewed in detail. Classical radiochemical procedures commonly been used in various samples, but neutron activation is probably more popular in environmental and biological samples. Gamma-spectrometric methods are often used in conjunction with Nt A. 

Radiochemical separations involved in conventional postirradiation RAA have some special characteristics that distinguish them from separation procedures used in classical trace element analysis. ... 

Classical or wet chemistry analysis techniques such as titrimetry and gravimetry remain in use in many laboratories and are still widely taught in Analytical Chemistry courses. They provide excellent introductions to the manipulative and other skills required in analytical work, they are ideal for high-precision analyses, especially when small numbers of samples are involved, and they are sometimes necessary for the analysis of standard materials. However, there is no doubt that most analyses are now performed by instrumental methods. Techniques using absorption and emission spectrometry at various wavelengths, many different electrochemical methods, mass spectrometry, gas and liquid chromatography, and thermal and radiochemical methods, probably account for at least 90% of all current analytical work. There are several reasons for this. 

For most applications in the use of tracers the most important factor in regard to purity of the labeled compounds is radiochemical purity. However, it is almost as important that the chemical purity or identity of the labeled compound be clearly established. Most classical methods for determination of chemical purity (melting point, UV, NMR, etc.) are usually inadequate for determination of radiochemical purity. The two basic techniques widely used to determine radiopurity are radiochromatography and reverse isotope dilution analysis. 

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