Forensic sciences alkaloids

Analysis of alkaloids, barbiturates, and other drugs and poisons in forensic science 97AC123R. 

Distinction should be made at this time between diastereoisomers and enantiomers. The former are characterized by the presence of at least two closely associated asymmetric centers in the molecular structure, either of which can epimerize. Altogether then there are two pairs of enantiomers for a total of four stereochemically unique individuals. Diastereoisomers have different physical properties and as a result discriminations, and even separations, can be done relatively easily. Enantiomers on the other hand differ in only one physical property, i.e. the direction of rotation of polarized light. Reaction of an enantiomeric racemic mixture with a third chiral species will produce a mixture of diastereomers therefore facilitating their identification or their separation. Early examples of this were the separations done by fractional crystallization of salts produced by a derivatization reaction with, for example, the alkaloid (-)-brucine. Fractional crystallization would never seem to be an effective analytical method yet it was used with some success in a forensic sciences context to confirm the presence of (L)-cocaine by a carefully contrived microcrystalline test. The physical properties... 

Tropane alkaloids include some medicinally important secondary plant metabolites as atropine (racemic mixture of 1- and d-hyoscyamine) and scopolamine. This group also includes cocaine, which, since it is a major drug of abuse, is frequently analyzed in forensic science. GC analysis of this class of compounds was first shown to be possible by Lloyd et al. in 1960. 

Japp M, Gill R, Osselton MD (1987) The separation of lysergide (LSD) from related ergot alkaloids and its identification in forensic science casework samples. J Forensic... 

Darby SM, Miller ML, and Allen RO (2001) Forensic determination of ricin and the alkaloid marker ricinine from castor bean extracts. Journal of Forensic Sciences 46 1033-1042. 

CE presents potential advantages in forensic science to carry out the analysis of opium alkaloids, as it can be in the different applications being published. Nevertheless, the lack of the sensitivity required for this type of analysis is always a great problem. One of the most basic approach for sensitivity enhancement is based on increasing analyte mass loading via online sample preconcentration techniques. The most widely employed in the analysis of major alkaloids is FASI that basically consists in a mismatch between the electric conductivity of the sample and that of the miming buffer. It is achieved by injecting the sample diluted in a solvent of lower conductivity than that of the carrier electrolyte. Upon the application of the... 

Lebelle, M. J., et aL "Gas Qiromatographic-Mass Spectro-metric Identification of Chiral Derivatives of the Alkaloids of KHAT." Forensic Science International, 611993,53-64. 

Dawson, B. A., et aL "Nuclear Magnetic Resonance Identification of the Fhenylalkylamine Alkaloids of Khat U g a Chiral Solvating Agent." Journal if Forensic Sciences, 39, no. 4,1994,1026. 

Applications of UV Raman are in the fields of biological and materials science, biochemistry, forensic sciences, etc., whereas application areas for both NIR and VIS Raman are polymers, polymerisation, paints, dyestuffs, pharmaceutical materials, alkaloids, minerals, explosives, multilayer films, hard disk quality control, etc. Especially NIR FT Raman spectroscopy finds promising applications in various fields, from latex systems [180] to textiles [181], Hendra et al. [182] and Schrader [183] have recently described application of NIR FT-Raman spectroscopy in the polymer industry. 

Py/GC, Py/GC/MS, and HPLC/MS are routinely used for the analysis of pure and formulated drugs or for the detection of active principles and metabolites in body fluids. The Py/GC method is used for detection of sulfonamides, barbiturates, and alkaloids such as morphine heroine, phenacetin and caffeine (often used in forensic science). 

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