Detailed background
Cocaine - A Brief Overview
A History of the Study of Cocaine in Hair
The Controversy of Hair Testing
General Procedures of Hair Testing
Detailed Procedure to Extract Compounds
A Few Chemical Structures
Works Cited
GC-MS tutorial
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The Detailed Procedure Used to Extract Compounds

Approximately 40 mg of pre-wash hair was weighed out and treated with 1 mL of 0.1 M HCl. The solution was allowed to sit for 18 hours in a stoppered test tube at 50C. The samples were heated using a Pierce Reacti-therm heating module.

The solution was neutralized with 0.1 M NaOH. 2 mL phosphate buffer, made from potassium phosphate salt, at pH 9.2, was added to the solution. The solution was extracted with chloroform/isopropanol/n-heptane (50:17:33 v/v) twice. After shaking and centrifugation, the test tube was put under a nitrogen stream to evaporate the organic phase.

The sample was derivatized using 100 microliters of heptafluorobutyric anhydride and 70 microliters hexafluoropropanol for 30 minutes at 60C. After drying, the samples were reconstituted in 100 microliters of ethyl acetate. GC-MS spectra were taken using an HP 5890 GC-MS. The column temperature was programmed from 40C to 200C at 12 C/min. The injector temperature was set to 200, 250, and 300C and the GC-MS interface was set at 230, 280, or 320C. The MS was run in single ion mode and the selected ions were 82, 182, and 303.


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