A9-tetrahydrocannabinolic acid

Figure 7 CEC step gradient of basic, neutral, and acidic compounds. Initial conditions (for first minute) acetonitrile/25 mM phosphate buffer pH 2.5 (60/40) with 2-mL/min hexylamine. Final conditions acetonitrile/25 mM phosphate buffer pH 2.5 (75/25) with 2-mL/min hexylamine. A voltage of 25 kV and a temperature of 20°C was used. Analytes (i) phenobarbital, (j) diazepam, (I) testosterone, (m) cannabinol, (n) testosterone propionate, (o) A9-tetrahydrocannabinol, and (p) A9-tetrahydrocannabinolic acid. (Reprinted from Ref. 46, with permission.)...

In order to identify cannabis products, one of the most frequently used methods is gas chromatography-mass spectrometry (GC-MS). The identification relies on the presence of A9-THC, CBD and CBN in the sample, and to a lesser extent, the presence of A8-THC (the isomer of the active principle of cannabis) and A9-tetrahydrocannabinolic acid. The following presents a method that has been found to work, although there are a number of similar methods reported in the literature [9], The sample is prepared for GC-MS analysis as follows ... 

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