Introduction
A suspected white powder was seized from the crime scene and sent to the laboratory for analysis. Presumptive test was firstly used in order to find out if it was a positive drug, in order to follow a further analysis.
Gas Chromatogram (GC) and mass spectrum was used for further analysis, in order to find out what exactly was this drug, and find its mixtures and compounds.
Results
From the chromatogram/spectrum peak report it is shown that there are two retention times of 15.67 and 9.66. The first peak has 9.66 retention time and has one possible match out of the five which is included in appendix 1.The highest match is ecgonidine, methyl ester (EDME) with 944 match and a 953 reverse match. EDME is a product of the thermal decomposition of cocaine and has been identified as a likely candidate for the detection of concealed cocaine (Analytical Chemistry 1997). The second peak, which has a 15.67 retention time, has also five possible matches, (see appendix 1). From the peak report it can be said that the highest match for the unknown peak is cocaine, as it has the highest match of 934 and a reverse match of 946.
Discussion
GC is an analytical technique for separating compounds based on their volatilities. It both provide qualitative and quantitative for individual compounds present in a sample. The compounds from the white powder move through a GC column, which in this case, as it is a solid element, it is heated and vaporized into a gaseous state. This column contains the stationary, high boiling point. As the mixture goes back and forth through the column, the components are separated. This instrument works out effectively as every component has a boiling point (retention) which is separated into single individual components. Just as the compounds exit the instrument, there is a detector, which is picked up by the electronics. This is the mass spectrum where it records and responds by printing peaks onto the paper.
Formal
Bibliography: Analytical Chemistry, Pavel Neudorfl, Pierre Pilon, and André H. Lawrence, 1997, pg 4283-5 Chemical Science and Technology Laboratory (CSTL), cocaine, http://webbook.nist.gov/cgi/cbook.cgi?ID=50-36-2