Determination of Menthol in Plasma and Urine by Gas Chromatography/Mass Spectrometry (GC/MS).
Menthol, a monoterpene, is a principal component of peppermint oil and is used extensively in consumer products as a flavoring aid. It is also commonly used medicinally as a topical skin coolant; to treat inflammation of the mucous membranes, digestive problems, and irritable bowel syndrome (IBS); and in preventing spasms during endoscopy and for its spasmolytic effect on the smooth muscle of the gastrointestinal tract. Menthol has a half life of 3-6 h and is rapidly metabolized to menthol glucuronide which is detectable in urine and serum following menthol use. We describe a method for the determination of total menthol in human plasma and urine using liquid/liquid extraction, gas chromatography/mass spectrometry (GC/MS) in selected ion monitoring mode and menthol-d4 as the internal standard. Controls are prepared with menthol glucuronide and all samples undergo enzymatic hydrolysis for the quantification of total menthol. The method has a linear range of 5-1000 ng/mL, and coefficient of variation <10%.
Methods in molecular biology (Clifton, N.J.)
Antipruritics; Flavoring Agents; Gas Chromatography-Mass Spectrometry; Humans; Irritable Bowel Syndrome; Liquid-Liquid Extraction; Menthol; Plant Oils
Irritable Bowel Syndrome; IBS; Peppermint Oil; Lab Tests
Peat, J., Frazee, C. C., Kearns, G., Garg, U. Determination of Menthol in Plasma and Urine by Gas Chromatography/Mass Spectrometry (GC/MS). Methods in molecular biology (Clifton, N.J.) 1383, 205-211 (2016).