Scott Reagent for Cocaine

This is a modification of the previous test, with the reagent consisting of a 2 (wt vol) solution of cobalt isothiocyanate in water, diluted with an equal volume of glycerine (1), concentrated hydrochloric acid (2) and chloroform (3). Testing for cocaine is carried out as follows. A small amount of the material is placed in a test-tube and five drops of component (1) added, when a blue colour will develop if cocaine is present. One drop of concentrated hydrochloric acid (2) is then added and...

Identification of Other Materials

If the morphological characteristics of Cannabis sativa are not all present, or if they have been destroyed, in, for example, resinous material or material that has been smoked (Plate 4.4), it is necessary to identify the material through its phytochemical content. This is also true for hash oil, and all three materials will be considered in the following sections. This involves the identification of the principle drugs which characterize the plant, namely A9-tetrahydrocannabinol (THC), CBD and...

Quantification of Cocaine by GCMS

This method relies on the response of the detector being in direct proportion to the concentration of drug in the sample being evaluated. A series of standards of known concentrations is prepared and analysed, with each analysis being separated by a blank. Why should each sample be separated by a blank in the analytical process The same solution system must be used to prepare both the standards and the samples. Why are internal standards necessary Why is there a requirement to use the same...

Presumptive Tests for Cocaine

There are a number of presumptive tests for cocaine available from the literature. These are described below. 6.3.1.1 The Cobalt Isothiocyanate Test Although there are several presumptive tests available for cocaine and related compounds, none alone is specific to cocaine itself. A very simple test for cocaine is the addition of the material under investigation to a 2 (wt vol) solution of cobalt isothiocyanate in water. The presence of cocaine and related alkaloids results in a blue colour...

Definitive Identification of Cocaine

GC-MS is routinely applied to the identification of cocaine. This is because the technique is both sensitive and of very high resolution. However, this method can also be used on simple mixtures. Trace samples should be obtained by swabbing the surfaces to be examined and subsequently processing the swabs by eluting the drug using methanol or ethanol. Where bulk samples are to be analysed, the sample should be thoroughly homogenized in preparation for this. Derivatization is frequently used and...

Analytical Sequence Bulk and Trace Sampling Procedures

Prior to the process of identifying whether or not a material contains cannabis or its products, a decision must be made as to whether the sample is a bulk or a trace sample. A bulk sample can be defined as anything that can be seen (herbal material, resin or oil), while a trace sample, in terms of cannabis, can be loosely defined as one which would easily be contaminated. Trace samples might be present, for example, on the surfaces of scales used to weigh cannabis materials, the surfaces of...

Identification Quantification and Comparison of Khat Samples

There are few reports in the literature of analyses of material from C. edulis and the only known prosecution for the production of cathine and cathinone from Khat (R. vs. Farmer, Lewes Crown Court, 1998) was unsuccessful 5 . Nevertheless, it is still necessary and useful to understand how to identify, quantify and compare such materials. 7.2.1.1 Identification and Quantification of Khat Basic forensic science principles should be adhered to when carrying out the analysis of a Khat seizure....

Thin Layer Chromatography

Prior to the use of any further method for the analysis of the material and identification of cocaine, the latter must be extracted. For powdered samples, which have been thoroughly homogenized, a 1 mgml-1 solution in methanol will suffice. For herbal material, the situation is rather more complex if the problems associated with extraction of chlorophyll, etc. are to be avoided. One study, where methanol and ethanol alone and in the presence of either diethylamine or ammonia were used,...