Sample preparation is the key step in determining low concentrations of pollutants from food, biological, plant, industrial, and environmental matrices. Solid-phase microextraction (SPME) is a solvent-free, cost-effective, robust, and high-throughput sample preparation technique [1] usually coupled with gas chromatography (GC). It is especially versatile for sampling volatile organic compounds (VOCs) not only present in the analysis of wine bouquet or cheese aromas [2], but also in cigarette smoke [3], or in the identification of microplastics (MPs) [4]. The sorption of VOCs on the SPME fibre in the headspace (HS) of the sample depends on numerous parameters: the type of fibre, the extraction time, and the temperature. Mixed-polarity phase SPME fibres (DVB/CAR/PDMS; Supelco, Bellefonte, PA, USA) were used in all analyses, from Nanos cheese to MP identification to cigarette smoke. The HS-SPME method enabled the VOCs’ profile study of Nanos cheese. The evolved cheese aroma profiles were affected by cheesemaking parameters: the amount of starter culture, ripening temperature, and media, and were independent of the geographical origin of raw milk as well as the location of ripening [2]. Further, by employing the HS-SPME-GC–MS method, identification of the five most common polymer types (PVC, PS, PET, PP, and PE) of MPs was possible. The well-controlled melting process, which generates characteristic compounds of each polymer, enabled the classification of MPs from real mixtures. Studying other VOCs concerning public health also included HS-SPME of flavours in tobacco products [classic cigarettes (CCs), electronic cigarettes (ECs), and heat-no-burn products (HNB)]. Flavours are the most common reason for promoting smoking initiation and duration, and they make smoking cessation more difficult among adolescents. However, the lack of simple smoke/aerosol/vapour (S/A/V) analyses for comparison of CCs, ECs, and HNB makes legislation or prohibition of such products impossible. It would be of general interest if a simple, standardised method existed.
Author Contributions
Conceptualisation, M.B.K.; methodology, U.Š. and M.B.K.; validation, U.Š.; formal analysis, M.B.K. and U.Š.; investigation, M.B.K., P.T., U.Š. and B.P.; resources, P.T.; data curation, M.B.K.; writing—original draft preparation, M.B.K., P.T., U.Š. and B.P.; writing—review and editing, M.B.K., P.T. and U.Š.; visualisation, M.B.K.; supervision, M.B.K. and P.T.; project administration, P.T. and B.P.; funding acquisition, M.B.K., P.T. and B.P. All authors have read and agreed to the published version of the manuscript.
Funding
This research was funded by ARRS P3-0388 for support through the programme “Mechanisms of Health Maintenance” and the post-graduate research funding programme Young Researchers (SP-0510/21 and 100-22-0510).
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
Not applicable.
Acknowledgments
The authors acknowledge Iva Boltar for contributing to this research work.
Conflicts of Interest
The authors declare no conflict of interest.
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