ABSTRACT
Chapter 2.3 of the European Pharmacopoeia general Chapter 2.3 includes identifications for the monograph 2.3.1, and also identifies reactions of ions and functional groups. These identifications consist of 35 simple tests each aiming at identifying, with some certainty, that the examined substance contains the specific ion or functional group giving name to the test. The tests share the common feature that they can be performed at the laboratory bench top without using analytical equipment. The tests are divided into two categories based upon the analytical/chemical principles (precipitations and color reactions) by which they were founded. However, they are very different in terms of selectivity, sensitivity, and ruggedness toward interferences. The aim of this chapter is to give the reader some insight into the principles of the individual tests and to be the starting point for further investigations. This starting point is based either upon determining whether one such study is needed as part of an out of specification investigation or whether a decision to reference the test when developing a new monograph is necessary.
