Jana Hajslova

Jana Hajslova is a professor at UCT Prague. She is the head of ISO 17025/2018 accredited laboratory and also heads a research group concerned with separation science in the field of food/environmental analysis. She is the chair of a series of prestigious international symposia, Recent Advances in Food Analysis (RAFA, www.rafa2021.eu).

Articles by Jana Hajslova

High performance liquid chromatography (HPLC) is a technique in analytical chemistry used to separate, identify, and quantify each component in a mixture | Image Credit: © Love Employee - stock.adobe.com

Scientists used supercritical fluid chromatography (SFC) and ultrahigh-pressure liquid chromatography (UHPLC)—both coupled with high-resolution mass spectrometry (HRMS)—to analyze various types of chlorinated paraffins (CPs) in fish oil-based dietary supplements.

In this study, SFC and UHPLC—both coupled with HRMS—methods for the analysis of short-, medium-, and long-chain CPs in fish oil-based dietary supplements were developed and validated at concentration levels of 0.6 and 3.0 µg/g lipid weight (lw).

A simple LC–MS method has been developed and validated for the simultaneous determination of 18 synthetic food additives and caffeine in soft and energy drinks, and in various alcoholic beverages. Nine food colours (tartrazine, sunset yellow FCF, azorubine, ponceau 4R, allura red AC, patent blue V, brilliant blue FCF, green S, brilliant black BN), two preservatives (sorbic and benzoic acid) and seven sweeteners (acesulfame K, aspartame, cyclamic acid, saccharin, sucralose, neohesperidin DC, neotame) were targeted food additives. The method employs reversed-phase ultra-high performance liquid chromatography (UHPLC) for analyte separation and a single quadrupole mass spectrometer for their detection. The limits of quantification were low enough to enable a reliable control of maximum limits set for some additives (Regulation [EC] No. 1333/2008). The method was applied for analysis of a wide range of samples collected at a typical supermarket: 14 soft drinks, 19 energy drinks, and 43 alcoholic beverages.

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A simple ultrahigh-performance liquid chromatography high resolution tandem mass spectrometry (UHPLC−HRMS/MS) method to determine seventeen phytocannabinoids was developed and validated for Cannabis plants, resins and their extracts, and oils. The analysis was challenging because of the complexity of matrices, the large differences in the concentration of phytocannabinoids and their pattern in various cultivars, and the structural similarity of these analytes.

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Mycotoxins, toxic secondary metabolites of several fungal species, represent food safety issues of high concern. Deoxynivalenol, the most abundant trichothecene mycotoxin, can be found worldwide as a contaminant of wheat, barley, maize and other cereals (1,2). The transmission of deoxynivalenol from barley into beer has been reported in several studies (3,4). Therefore, its levels should be controlled.

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The potential of the time-of-flight mass spectrometry (TOF-MS) to innovate the analysis of soft drinks is described using gas chromatography (GC) hyphenated to TOF-MS and a new type of ion source, direct analysis in real time (DART), coupled to high-resolution TOF-MS. Head-space solid-phase microextraction (SPME) was used to isolate/extract volatile compounds followed by GC–TOF-MS to identify tainted compound in contaminated soft drinks. Direct analysis in real time–time-of-flight mass spectrometry (DART–TOF-MS) was also used to obtain negative and positive ion profiles of different soft drinks to determine the presence of various compounds, including antimicrobial preservatives, artificial sweeteners, acidulants and saccharides, without any sample preparation and chromatographic separation.

Gas chromatography (GC) coupled to time-of-flight mass spectrometry (TOF-MS) offers unique solutions for various analytical applications including the analysis of food quality, authenticity and safety markers. This article provides a general overview of TOF-MS basic features, highlighting its advantages and limitations compared with GC conventional mass analyzers. Examples of recent results obtained selected food contaminants and flavor components are described illustrate the potential of this recently introduced technique.

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Gas chromatography (GC) coupled to time-of-flight mass spectrometry (TOF-MS) offers unique solutions for various analytical applications including the analysis of food quality, authenticity and safety markers. This article provides a general overview of TOF-MS basic features, highlighting its advantages and limitations compared with GC using conventional mass analysers. Examples of recent results obtained for selected food contaminants and flavour components are described to illustrate the potential of this recently introduced technique.