Reference no: EM133265472
Question - Analysis of an unknown drug sample.
Case scenario: At the crime scene a bag with white powder was collected. The bag with powder is taken to the lab for analysis. The Modified Scott's color test reveals possible presence of cocaine in the powder.
As the forensic analyst in this case your task is to confirm the presence of an illicit substance in the powder and the amount present in the powder to corroborate with possible illicit use/possession of the substance. Following the SWGDRUG guidelines design an analytical approach for the confirmation and quantitation of cocaine in the powder. Assume you can use any instrumentation listed in the SWGDRUG guidelines.
The analytical design should include the following steps:
1. Drug information
Find the following information about cocaine:
Picture of molecular compound: include in the "Drawing page"
Indicate whether is a depressant, stimulant, or opioid/opiate
Schedule:
Formula:
Molecular weight: ___ g/mol
Boiling point:
Solubility:
pKa:
*If any of the information is not available please indicate.
2. Presumptive tests
A. Describe how the Modified Scott's color test is performed for the collected sample. Provide as much detail as possible (chemical equations are not required). What is the color test result?
B. Before the confirmatory analysis, which is another test you could perform? Explain your reasoning. *Use tests for identification purposes, not confirmation.
3. Sample preparation
A. For the confirmatory analysis, how would you prepare the sample? Describe the sample preparation process, include the weighing process, amount of sample to be used, solvents and reagents used, etc... *It will be useful to imagine you are in the lab preparing the sample.
B. Explain your reasoning for selecting the sample preparation steps described above. *To design the most appropriate sample preparation, consider the instrument you will use for the confirmatory analysis.
4. Confirmatory analysis
A. What instrument(s) are you going to use for the confirmatory identification and quantitation of cocaine in the sample? Explain your instrument selection.
B. Describe how you will perform the analysis of the sample using the instrument(s) selected. Describe the identification and quantitation analytical process. *Think of any additional sample preparation and introduction into the instrument.
5. Data interpretation
A. Confirmatory identification (qualitative analysis). What information are you expecting to obtain from this analysis that will indicate the presence of cocaine? *Analytical information could include the chromatogram's peak retention time, spectrum, etc...
B. Quantitative analysis. What information was obtained in the analysis that will allow you to determine the quantity of cocaine in the sample? Explain the data processing steps to quantify the amount of cocaine in the sample.