Applications of 13C NMR to metabolic studies.

It is our view that the above examples, most of which have been published in the last two years, represent the beginnings of a new field and that in spite of major problems in instrumentation and programming, the essential feasibility of using enriched 13C substrates for metabolic processes as a noninvasive technique has been firmly established. With the caveat that a rigorous protocol for signal assignment must be devised, we can look forward to many applications of this method in a wide range of biological systems.