Page 255 - Radiochemistry and nuclear chemistry

CHAPTER 9

Uses of Radioactive Tracers

Contents

9.1. Basic assumptions for tracer use 240
9.2. Chemistry of trace concentrations 241
9.2.1. Adsorption 242
9.2.2. Radiocolloids 243
9.2.3. Equilibrium reactions 243
9.2.4. Precipitation and crystallization 244
9.2.5. Electrochemical properties 245
9.2.6. Tracer separation methods 246
9.3. Analytical applications 248
9.3.1. Radiometric analysis 248
9.3.2. Isotope dilution analysis 249
9.3.3. Activation analysis 251
9.3.4. Substoichiometric analysis 255
9.4. Applications to general chemistry 256
9.4.1. Determination of chemical reaction paths 257
9.4.2. Determination of chemical exchange rates 259
9.4.3. Determination of equilibrium constants 261
9.4.4. Studies of surfaces and reactions in solids 264
9.5. Applications to life sciences 266
9.5.1. Biological affinity 267
9.5.2. Transmission computer tomography (TCT) 269
9.5.3. Emission computer tomography (ECT) and diagnosis 271
9.5.4. Radiation therapy with internal radionuclides 276
9.6. Industrial uses of radiotracers 277
9.6.1. Mixing 277
9.6.2. Liquid volumes and flows 278
9.6.3. Wear and corrosion 278
9.6.4. Chemical processing 279
9.7. Environmental applications 279
9.8. Exercises 280
9.9. Literature 281

In this chapter some of the ways in which radiochemistry has aided research in various
areas of chemistry and related sciences are reviewed.
The first experiments with radioactive tracers were conducted in 1913 by de Hevesy and
Paneth who determined the solubility of lead salts by using one of the naturally occurring
radioactive isotopes of lead. Later, after discovery of induced radioactivity, de Hevesy and
Chiewitz in 1935 synthesized 32p (/~- t,/2 14.3 d) and used this tracer in biological studies.
In the same year de Hevesy and co-workers also carried out activation analyses on rare

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