Leachables chemical entities

Note, however, that the chromatogram shows this additive to be in reality a complex mixture of chemical entities, all of which could appear as extractables/ leachables. 

Each chemical entity identified as a drug product leachable under appropriate stability storage conditions was also identified as an extractable from one or more container closure system component (i.e., qualitative correlation). 

As described above, individual packaging components will invariably contain complex mixtures of chemical entities (e.g., additives and oligomers), many if not most of which are at relatively trace levels (i.e., pg/g and lower). The principles of Trace Organic Analysis, as developed in the environmental, geochemical, and bioanalytical fields, can be applied to the problem of identification and quantification of these individual chemical entities, whether as extractables or as leachables.f The general process is as follows ... 

To be amenable to gas chromatographic analysis, a compound must volatilize without thermal decomposition and not interact with the analytical system in such a manner so as to cause irreversible surface adsorption or surface catalyzed decomposition. In addition, the polarities of the various chemical entities to be analyzed must be considered so that an appropriate GC separation mechanism (i.e., partitioning, adsorption, etc.) can be chosen. Although these factors might seem to suggest that GC is a very selective analytical technique, in fact a wide variety of chemical entities which can appear as extractables and leachables are amenable to GC separation and analysis. ... 

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