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In this study, various anionic chiral selectors were investigated for the capillary electrophoresis (CE) separation of six chiral phenethylamines and three achiral neutral impurities which are commonly identified in illicit methamphetamine. Analyses were carried out at pH 8 (high osmotic flow) with untreated capillaries using 25 mM chiral surfactant or 10 mM charged cyclodextrin. The chiral selectors included the micelle (R)-N-dodecoxycarbonylvaline (EnantioSelect (R)-Val-1) (ES) and the cyclodextrins sulfobutyl(IV)-ether-beta-cyclodextrin (SBE(IV)-beta-CD) (BSB4), SBE(VII)-beta-CD (BSB7), SBE(XII)-beta-CD (BSB 12), SBE(IV)-gamma-CD (GSB-4), SBE(VII)-gamma-CD (GSB-7), sulfated(XI)-alpha-cyclodextrin (SU(XI)-alpha-CD (AS11), SU(VII)-beta-CD (BS7), SU(XII)-beta-CD (BS12) and SU(XIII)-beta-CD (GS13). Enantiomeric and achiral selectivity strongly depends on the size of the CD, the average degree of substitution, and the type of substitution. ES exhibits good performance for the neutral solutes, but exhibits enantiomeric selectivity only for the alpha-hydroxyphenethylamines. GS13 provides the best overall enantiomeric selectivity. All fifteen solutes related to methamphetamine are simultaneously separated using BSB7.

The rationale for developing cocaine profiling methodology is described. Current cocaine signature procedures in use at the U.S. Drug Enforcement Administration's Special Testing and Research Laboratory are reviewed. Newer selective and sensitive methodology, recently developed, is described. That methodology detects more alkaloidal impurities in refined illicit cocaine than heretofore reported. The alkaloidal impurities were isolated from the bulk cocaine matrix by alumina column chromatography and detected using capillary gas chromatography-mass selective detection in the selected ion mode. Fifty-one refined illicit cocaine samples were subjected to this methodology for the determination of 15 selected alkaloids. Reproducibility data are reported. Methodology for the isolation, detection, and characterization of coca alkaloids in South American coca leaf, a commercial coca-leaf extract, and a large seizure of refined illicit cocaine is reviewed., (Copyright © 1998 Central Police University.)

The analysis of by-products and impurities in illicit cocaine, including the isomeric truxillines, is important for derivation of both strategic and tactical intelligence. In the present study, various capillary electrophoresis techniques were investigated for this purpose. The use of the anionic beta-cyclodextrin sulfobutyl ether IV as a run buffer additive at pH 8.6 gave a good separation of the truxillines and similar high molecular weight impurities in less than eight minutes. These impurities were first isolated from the bulk cocaine matrix using liquid-liquid extraction and size-exclusion high performance liquid chromatography. There was a red shift in the UV spectra obtained for the truxillines using photodiode array (PDA) UV detection during CE analysis. This anomalous behavior is attributed to photo-degradation of the truxillines during the PDA-UV irradiation process. Laser-induced fluorescence detection using a UV krypton/fluoride laser provided greater selectivity and sensitivity versus UV detection for certain uncharacterized high molecular weight impurities.

Several novel chlorinated tropanes were produced when cocaine was treated with aqueous sodium hypochlorite. Two of these, 2'- and 3'-chlorobenzoyloxy-2-carbomethoxypseudotropine (that is, ortho- and meta-chlorococaine), were characterized by synthesis and gas chromatography/mass spectrometry. Four other new chlorinated tropanes (endo-6- and 7-chlorococaine, exo-6- or 7-chlorococaine and N-chlorobenzoylnorecgonine methyl ester) were also tentatively identified via their gas chromatography retention data and mass spectra. The results are of potential use in cocaine signature and comparative analysis.

Methodology is presented for the isolation, identification and determination of pseudococaine in coca leaves and illicit cocaine. Coca leaves, crude cocaine base (coca paste), refined cocaine base and refined cocaine hydrochloride, all derived from the same geographic location in Bolivia, were examined. Pseudococaine and other coca alkaloids were isolated from leaf samples using toluene extraction followed by acid/Celite trap and ion-pair column chromatography, and from crude and refined cocaine samples by acid/Celite column ion-pairing chromatography. Mass spectral analysis of coca leaf isolates confirmed the presence of pseudococaine. Pseudococaine was quantified by capillary gas chromatography with flame ionization detection at levels of 0.0001-0.035% (relative to cocaine) in refined illicit cocaine and coca leaves.

The predominant methods currently used for illicit production of cocaine are described. For illicit natural cocaine (i.e., from coca leaf), this includes production of coca paste from coca leaf via both the solvent and acid extraction techniques, purification of coca paste to cocaine base, and conversion of cocaine base to cocaine hydrochloride. For illicit synthetic cocaine (i.e., synthesized from precursor chemicals), the classic five-step synthetic route used in all clandestine laboratories seized to date is summarized. The origins of the most common alkaloidal impurities and processing/synthetic by-products typically identified in illicit natural, illicit synthetic, and pharmaceutical cocaine are discussed. Forensic differentiation of exhibits arising from the various production methods are addressed both in terms of overall product purity and the presence/absence of these impurities and by-products., (Copyright © 1993 Central Police University.)

A simple aqueous extraction method for the isolation and identification of psilocin from Psilocybe cubensis mushrooms is reported. This method employs a dephosphorylation of the phosphate ester to psilocin, which facilitates a greater product yield and simplifies identification. Psilocin extracted by this method is sufficiently concentrated and free of cocontaminants to allow identification by infrared spectroscopy and gas chromatography/mass spectrometry.