570 Tracer Techniques /30 : 8 



8. Summary 



Tracer techniques use unusual isotopes in many different ways. In this 

 chapter, examples were cited of studies on a pathway of synthesis, on 

 the fate of an ingested compound, on a turnover or resynthesis rate, and 

 on a life span of a given cell type. In other chapters in this text, reference 

 has been made to isotope tracer studies. These have been included in 

 discussions of the role of viruses in Chapter 14 and of studies on active 

 transport in Chapter 23. 



The use of tracers depends upon several factors, namely, their avail- 

 ability from reactor and cyclotron bombardments, their half-lives, the 

 energies of their radiations, the availability of suitable detecting equip- 

 ment, and the concentration of the element in the living system. Tracer 

 experiments make possible studies of kinetic rates and reaction mechan- 

 isms, without interfering with the chemical equilibria. 



REFERENCES 



A large number of books have been written on the use of tracer techniques. 

 It is hard to open a journal dealing with physiology, or biochemistry, or 

 biophysics, and avoid reading articles using tracer techniques. The following 

 references are only meant to be typical, not complete. 



1. Lawrence, J. H., and J. G. Hamilton, eds., Advances in Biological and Medical 

 Physics (New York: Academic Press, Inc., 1948) Vol. 1; 1951, Vol. 2. 



a. Lawrence, J. H., and C. A. Tobias, eds., Advances in Biological and 

 Medical Physics (New York: Academic Press, Inc., 1953) Vol. 3. 



2. Arnoff, Samuel, Techniques of Radiobiochemistry (Ames, Iowa : Iowa State 

 College Press, 1956). 



3. Comar, C. L., Radioisotopes in Biology and Agriculture : Principles and Practice 

 (New York: McGraw-Hill Book Company, 1955). 



4. Kamen, M. D., Radioactive Tracers in Biology 2nd ed. (New York: Academic 

 Press, Inc., 1951). 



A complete table of isotopes and their products can be found in : 



5. Strominger, D., J. D. Hollander, and G. T. Seaborg, "Table of Isotopes," 

 Rev. Mod. Phys. 30: 42, Part II, 585-904 (1958). 



