Determination of cannabinoids by capillary liquid chromatography with electrochemical detection

✍ Scribed by U. Backofen; W. Hoffmann; F.-M. Matysik

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 48 KB
• Volume: 14
• Category: Article
• ISSN: 0269-3879
• DOI: 10.1002/(sici)1099-0801(200002)14:1<49::aid-bmc967>3.0.co;2-d

✦ Synopsis

Electrochemical detection (ED) in non-aqueous media in combination with capillary chromatography is applied to the determination of cannabinoids. Prior to chromatographic-ED analysis capillary batch injection analysis (CBIA) was utilized to select optimum detection parameters. It was found that tetrahydrocannabinol (THC) as well as other cannabinoids undergo electrochemical oxidation at a potential of 1.5 V (vs silver quasi-reference electrode) applied to a 25 mm Pt microdisk electrode. No effects of electrode fouling over an extended measuring period were observed. The limit of detection of 20 pg THC in capillary HPLC-ED was significantly lower compared to those in capillary HPLC-UV (65 pg) and conventional HPLC-UV detection (2 ng), respectively. A practical application concerning the determination of cannabinoids in hair is presented.