Direct immersion solid‐phase microextraction with gas chromatography and mass spectrometry for the determination of specific biomarkers of human sweat in melted snow

Abstract

Direct immersion solid-phase microextraction with gas chromatography and mass spectrometry for the determination of specific biomarkers of human sweat in melted snowTo provide a reliable tool for investigating diffusion processes of the specific components of the human odor 3-hydroxy-3-methylhexanoic acid and 3-methyl-3-sulfanylhexan-1-ol through the snowpack, we developed and optimized an analytical method based on direct immersion solid-phase microextraction followed by gas chromatography with mass spectrometry. Direct immersion solid-phase microextraction was performed using polyacrylate fibers placed in aqueous solutions containing 3-hydroxy-3-methylhexanoic acid and 3-methyl-3-sulfanylhexan-1-ol. After optimization, absorption times of 120 min provided a good balance to shorten the analysis time and to obtain suitable amounts of extractable analytes. The extraction efficiency was improved by increasing the ionic strength of the solution. Although the absolute extraction efficiency ranged between 10 and 12% for 3-hydroxy-3-methylhexanoic acid and 2-3% for 3-methyl-3-sulfanylhexan-1-ol, this method was suitable for analyzing 3-hydroxy-3-methylhexanoic acid and 3-methyl-3-sulfanylhexan-1-ol concentrations of at least 0.04 and 0.20 ng/mL, respectively. The precision of the direct immersion solid-phase microextraction method ranged between 8 and 16%. The variability within a batch of six fibers was 10-18%. The accuracy of the method provided values of 88-95 and 86-101% for 3-hydroxy-3-methylhexanoic acid and 3-methyl-3-sulfanylhexan-1-ol, respectively. The limit of detection (and quantification) was 0.01 ng/mL (0.04 ng/mL) for 3-hydroxy-3-methylhexanoic acid and 0.06 ng/mL (0.20 ng/mL) for 3-methyl-3-sulfanylhexan-1-ol. The signal versus concentration was linear for both compounds (r 2 = 0.973-0.979). The stability of these two compounds showed that 3-hydroxy-3-methylhexanoic acid was more stable in water than 3-methyl-3-sulfanylhexan-1-ol. We applied the method to environmental samples in correspondence with an olfactory target buried previously.

Using surface-enhanced Raman scattering for simultaneous multiplex detection and quantification of thiols associated to axillary malodour

“… 19 Furthermore, using direct immersion SPME GC-MS, the LoD of 3M3MH was recorded as 0.06 ng mL −1 (0.06 ppb). 72 It is likely the detectability of the other three thiols using both methods is similar to 3M3MH. However, as previously discussed, these methods require further extraction and concentration to produce such low LoDs.…”

Environmentally friendly solid‐phase microextraction coupled with gas chromatography and mass spectrometry for the determination of biogenic amines in fish samples

“…Moreover, the classic extraction methods, such as LLE , SPE , can cause environmental pollution and harmful to manipulator owing to the consumption of a large amount of organic solvents (at the multiple milliliter level). To overcome these shortcoming, new sample preparation microextraction techniques, such as SPME , have gradually replaced SPE as an environmentally friendly pretreatment method because it possesses rapid, simple, sensitive characteristics, needs no or little organic extraction reagent, easy manipulation, linkup with detection instruments, and direct injection without elution while coupling with GC–MS for detection . In the study, we employed SPME for sample pretreatment and preconcentration of BAs to simplify the detection procedures.…”