Quantitation of monoterpenoid compounds with potential medicinal use in biological fluids

Bimolecular and unimolecular contributions to the disparate self-chemical ionizations of α-Pinene and camphene isomers

“…Chemical ionization (CI) mass spectra of terpenes have been reported [18] but the SCI of terpenes has not been studied previously. We present the first detailed studies on the SCI of ␣-pinene and ␣ camphene; here, SCI is referred to the formation of [M ϩ H] ϩ by reaction of either its fragment or M ·ϩ ions with neutral parent molecules (M).…”

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

“…Exposure to monoterpenes can be determined by biomonitoring of monoterpenes and/or monoterpene metabolites concentrations in biological fluids such as blood and urine from suspected exposed human subjects. The biomonitoring technique provides a very useful tool to estimate systemic uptake/exposure of man to monoterpenes and presents also an indication of the bioavailability of monoterpenes [16]. Previously, different studies reported the possibility of the determination of monoterpene systemic exposure by the analyses monoterpene alcohol concentrations from monoterpenes such as verbenol, a metabolite of ␣-pinene [17], 2␣-and 3␣-hydroxycineole [18] metabolites from 1,8-cineole and the 3 -carene metabolite, 3 -carene-10-ol [19] in urine samples.…”

Determination of menthol in plasma and urine of rats and humans by headspace solid phase microextraction and gas chromatography–mass spectrometry

“…In humans, few studies were performed to elucidate the pharmacokinetic profile of menthol and its main metabolite M-G, but not of other phase-I metabolites. For the quantification of menthol and M-G after enzymatic hydrolysis in plasma and urine different methods including liquid-liquid extraction or headspace sampling followed by analysis with GC and GC-MS were proposed [4][5][6][7][8][9][10]. In plasma unconjugated menthol was only detected after a transdermal application [5].…”

“…In plasma unconjugated menthol was only detected after a transdermal application [5]. The problem of methods basing on liquid-liquid extraction consists in loosing the lipophilic analytes by volatilisation [9], resulting in loss of recovery, sensitivity and precision. Concerning M-G, the use of high performance liquid chromatography (HPLC) for its direct determination would be an option to avoid such problems.…”

“…Concerning M-G, the use of high performance liquid chromatography (HPLC) for its direct determination would be an option to avoid such problems. Due to the lack of a chromophore, M-G needs to be derivatised [11,12] or MS has to be used to enhance sensitivity [9]. Headspace solid-phase microextraction (HS-SPME), an alternative sample extraction technique, allows to concentrate volatile and semi-volatile analytes from the headspace above the sample on a coated fiber and to transfer the analytes from the fiber directly into the injector port of a GC without further manipulations.…”