Radiotracers in Methodological Studies

Important information can be obtained rapidly and cheaply by radioindicators. Specific procedures for quantitatie determinations based on radiotracers (see Chaps. 8.4, 8.5) involve additional principles. 

Radioactive tracer analysis is based on the simple proportionality between the mass of analyte x and the radioactivity A initially added to the sample  

By adding a radioactive tracer before the individual process stage, and following it by radioactivity measurements, the recovery, distribution, and loss are measured independently of any additional risk of contamination. By means of nuclear activation, radioactive tracers can be introduced into solid samples and can be used to determine the recovery and loss during decomposition of solids, and separation from solid samples by volatilization, leaching, and solvent extraction [9], [10], [40], [51]-[64], [67]-[80], [93], [97], 

A variety of examples from the general analytical field [2], [7], [17], [25] and from trace element analysis [20], [33], [44], [46] covers separate stages of combined analytical procedures such as decomposition [20], [44], [45], evaporation [81], coprecipitation, adsorption, and washout of precipitates contamination and adsorption [18], [33], separation by chromatography, ion-exchange, liquid-liquid distribution, and electrodeposition [4], 133], [34], [38], [40], [41], [78]. 

Radioanalytical indicator methods (including the radioreagent method, see Chap. 8.5) experienced a revival in the 1960s and early 1970s. Modern direct instrumental methods [19] underemphasized the importance of radioanalytical methods, which are necessary to establish the accuracy of spectroscopic methods, to avoid systematic enors. and to assess trace content in SRMs. An important advantage is the ability to reveal accidental losses, even at the ultra-trace level. 

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