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Honey is the oldest and nowadays widely used natural sweetener for food worldwide. Its composition is associated with its botanical and geographical origin and honey is often mislabeled and has a high potential for food fraud. Thus, quick easy and sensitive analyses are required. For the first time, we developed and applied an automated, fast, sensitive and robust, in-tube extraction dynamic headspace in-tube extraction-dynamic headspace (ITEX-DHS) method for a variety of Honey containing VOCs in connection with GC-MS. Another advantage of ITEX is, that it is a green analytical solventless method. The method provides very low method detection limits (MDL) from 0.8 to 47 ng g-1 for VOCs in honey samples as well as very good repeatabilities with averages below 9 % RSD. Recoveries are between 83 and 100 %. Only octanal possess a repeatability 13 % and a recovery of 62 % due to its high polarity. 38 honey samples were measured after method validation. Four acacia honeys (A), six forest honeys (F) and 22 blossom honeys (B). The type of six honeys was not known (U) but could be predicted with the help of a linear discriminant analysis (LDA). The LDA was carried out with the three groups (A, B, F) leading to a proportion of correct predictions of 90.6 %. With the help of a scatterplot, two of the unknown samples were classified as forest honeys and four of them as blossom honeys.

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In this study the occurrence of polychlorinated biphenyls (PCBs), polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/PCDFs) in street dust samples was investigated using pressurized liquid extraction and gas chromatography coupled to mass spectrometry. Street dust samples were taken from rural, urban, industrial and industrially influenced urban areas. PCB6 concentrations ranged from 5090±2200 µg/kg (average±standard error of mean) in dusts from industrial premises to 29±8.7 µg/kg in rural areas. Concentration ranges were for dioxin-like PCB toxicity equivalents (dl-PCB TEQ) from 362±164 ng/kg (industrial premises) to 6.5±1.8 ng/kg (rural areas), and for PCDD/PCDF TEQ from 503±448 ng/kg to 2.4±0.13 ng/kg, respectively. Area concentrations of PCB6 (0.040 µg/m2-22 µg/m2), dl-PCB TEQ (0.0038 ng/m2-2.6 ng/m2) and PCDD/PCDF TEQs (14 pg/m2-1980 pg/m2) were estimated. Furthermore, particle size related concentrations of PCBs and PCDD/PCDFs in street dusts were analysed showing throughout almost all samples a distinctive trend of increasing concentrations with decreasing particle sizes. Characterization of homologue patterns of PCBs and PCDDs/PCDFs in street dusts was performed showing a dependence of homologue patterns on different area types, especially for PCBs. It could be demonstrated that the analysis of concentrations in combination with specific homologue patterns of PCBs and PCDDs/PCDFs in street dust samples enables allocation of potential emission sources.

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An in-tube extraction (ITEX) method for the GC-MS analysis of volatile constituents of alcoholic beverages was developed and applied in the analysis of 46 beers from six varieties, Alt, Helles, Kölsch, Pilsener beer, Schwarzbier, and wheat beer, which are popular in Germany. The extraction performance of nine different sorbent materials was evaluated. The best overall sensitivity was achieved using Tenax TA, with method detection limits down to 0.01 µg L-1, whereas the widest linear range was possible with PDMS, covering almost 5 orders of magnitude. This is the first application of PDMS in ITEX as a high-capacity extraction device and highlights the importance of choosing the appropriate sorbent material for the analytical task at hand. A satisfying chemometric discrimination of all analyzed beer varieties was possible, and alcohol-free beers could clearly be separated from regular beers, also.

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Wafers with varying concentrations of diphenhydramine hydrochloride (DPH-HCl) as active pharmaceutical ingredient (API) were prepared and their near infrared (NIR) and Raman spectra recorded. The purpose of this study was to compare the suitability of these two vibrational spectroscopic techniques for the quantification of DPH-HCl in pharmaceutical wafers. Partial least squares (PLS1) calibration models with different data pretreatments were tested. Both NIR and Raman spectroscopy proved to be suitable to predict DPH-HCl contents at lower concentration ranges. At higher concentrations, interference by crystallization processes was observed. For investigating the general applicability of the quantification methods, two commercially available products were examined.

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In open-path Fourier Transform Infrared spectroscopy, the generation of a suitable background single-beam spectrum is of major concern. The Shifting Method is a derivative-like approach to correct for the background without the need to actually measure a background spectrum using the sample single-beam spectrum. A thorough study of the Shifting Method was conducted. A set of guidelines was developed based on the results of artificial and closed cell data. These guidelines were applied to three different data sets, consisting of cell and open path data with multiple compounds, overlapping peaks, and high water vapor and aerosol levels.