Extreme trace analysis of the elements-I Methods and problems of sample treatment, separation and enrichment.

In the determination of elements in the ppM range in inorganic and organic matrices, solution techniques are useful because they simplify calibration problems and improve the limit of detection. The author reviews, in the light of his own experience, some 350 publications concerned with methods for the preparation and dissolution of samples and for the isolation of trace elements before their determination. The errors in these methods, made more difficult to reduce because of the additional operations required, are compared with those associated with the more direct methods.