Sensitive determination of monoterpene alcohols in urine by HPLC-FLD combined with ESI-MS detection after online-solid phase extraction of the monoterpene-coumarincarbamate derivates
- J Chromatogr B Analyt Technol Biomed Life Sci. 2008 Nov 15;875(2):444-50. doi: 10.1016/j.jchromb.2008.09.024.
- 1. University of Arkansas for Medical Sciences (UAMS), Center for Translational Research in Aging & Longevity (CTRAL), Donald W. Reynolds Institute on Aging, 4301 W Markham St., Little Rock, AR 72205, USA. [email protected]
A method was developed for the determination of the monoterpene alcohols verbenol, myrtenol, perillyl alcohol, alpha-terpineol, Delta(3)-carene-10-ol, thymol and p-alpha,alpha-trimethylbenzylalcohol in urine samples. After an enzymatic cleavage of their glucuronide- and sulfate conjugates the monoterpene alcohols were converted in the urine matrix with 7-diethylaminocoumarin-3-carbonylazide into monoterpene-[7-(diethylamino)-coumarin-3-yl]-carbamate derivates prior to analyses. Enrichment of the monoterpene alcohols from the urine matrix was achieved by online-solid phase extraction (SPE) with restricted-access material (RAM). After removal of excess derivatization reagent and urine matrix components, the monoterpene derivatives were separated by high-performance liquid chromatography (HPLC) in combination with fluorescence (FLD) detection and simultaneous mass spectrometric (MS) identification. Detection limits (LOD) for studied monoterpene alcohols ranged between 22 and 197 ng/L. The method was validated and successfully applied to urine samples from human subjects orally exposed to monoterpenes trough an intake of cough medication containing monoterpenes as active medicinal ingredients.