methods for impurity profiling of heroin and cocaine - United Nations ...

Aspects of drug characterization and impurity profiling 11
(c) Cutting agents added at any point in the distribution chain;
(d) Analytical procedure-generated artefacts.
A number of laboratories throughout the world are at present involved in the work
of impurity profiling. Those laboratories do not all have the same purpose for this
work nor do all of the laboratories pursue the same “easily detected impurities”
(analytical targets). Following this paragraph is a listing of the most common analytical
targets that these laboratories do pursue, two of which require the use of
relatively expensive analytical hardware not typically found in the majority of
forensic drug laboratories.
The resulting data are useful for:
1. Major components*
(a) Characterizing the target analyte heroin or cocaine;
(b) Screening samples for possible linkages (similar samples);
(c) Indicating region of sample origin;
(d) Characterizing cutting agents (adulterants and diluents).
The resulting data is useful for:
2. Trace components**
(a) Determining possible sample links;
(b) Indicating region of sample origin;
(c) Indication of processing or synthetic methods utilized.
The resulting data are useful for:
3. Residual and/or occluded solvents
(a) Determining possible sample links;
(b) Indicating region of sample origin (heroin only);***
(c) Identification of “last-step” processing solvents.
*Major components are generally the most abundant alkaloids, diluents and adulterants.
**Analysis of trace components generally requires an extraction step and is most frequently followed
by a concentration step.
***For cocaine, the analysis of residual and/or occluded solvents may only indicate the region in
which the hydrochloride was produced, but not where the coca bush was grown.