Justyna Płotka-Wasylka

Chemical derivatization processes applied to amine determination in samples of different matrix composition.

Amines are important biological compounds, and so their analysis and monitoring in various matrices is worthy of investigation and development.Due to the polar nature of amines, chromatographic analysis of free amines is generally unsatisfactory owing to adsorption and decomposition of the solute on the column, resulting in peak tailing and losses. Therefore, many derivatization reactions are employed to reduce the polarity, improve chromatographic separation of analytes, and increase selectivity and sensitivity of detection. In addition, the sample matrix contains other compounds at the same or higher concentration levels, making determination difficult and sometimes impossible. An important solution to this problem is derivatization of analytes, causing changes in their structures and properties, thus allowing differentiation of the analyte from other compounds present in the sample.A number of derivatization reactions including acylation, silylation or carbamate formation can be applied to amine compounds. In a chromatographic system, these reactions can be performed as pre-column, on-column, or post-column. Attempts have been made in both off-line and online approaches. Off-line derivatization is simple but time-consuming and labor intensive, particularly when large numbers of samples are involved and may increase the risk of loss or contamination. An alternative approach is to convert analytes by online derivatization using flow methods, so avoiding the drawbacks of off-line procedures. Online derivatization can be performed prior to chromatographic separation. This offers advantages for analytes with poor separation due to strong adsorption on the stationary phase, or labile compounds, which may easily decompose or react with other components during chromatographic separation.Solventless sample preparation techniques based on the extraction of analytes in sorption processes are effective and an environmentally friendly alternative to solvent extraction procedures. This type of extraction includes solid phase microextraction (SPME) and stir bar sorptive extraction (SBSE), with both techniques having been successfully applied to in situ derivatization of amine compounds. SPME and SBSE in combination with chromatographic techniques enable selective and sensitive analysis of amine derivatives in various matrices.Both techniques are simple and economical, do not require preliminary sample preparation steps, and reduce the volume of solvents used.

An in situ derivatization – dispersive liquid–liquid microextraction combined with gas-chromatography – mass spectrometry for determining biogenic amines in home-made fermented alcoholic drinks

A novel dispersive liquid-liquid microextraction (DLLME) gas chromatography mass-spectrometry (GC-MS) method was developed for the determination of 13 biogenic amines in home-made wine samples. The method allows to simultaneous extraction and derivatization of the amines providing a simple and fast mode of extract enrichment. During the study, two different procedures were examined. Statistical analysis was performed to choose better procedure, as well as the conditions of derivatization reaction. At least, a mixture of methanol (dispersive solvent; 215μL), chloroform (extractive solvent; 400μL), and isobutyl choloroformate (derivatizing reagent; 90μL) was used as extractive/derivatizing reagent, added to 5mL of sample. The addition of mixture of pyridine and HCl was necessary to eliminate the by-products. The proposed method showed good linearity (correlation coefficients >0.9961), good recoveries (from 77 to 105%), and good intra-day precision (below 13%) and inter-day precision (below 10%). Moreover, detection limits were never over 4.1μg/L. The developed method was successfully applied to the analysis of 17 home-made wine samples not regulated by law. All of the biogenic amines analyzed were found in most of the wines.

A new tool for the evaluation of the analytical procedure: Green Analytical Procedure Index

A new means for assessing analytical protocols relating to green analytical chemistry attributes has been developed. The new tool, called GAPI (Green Analytical Procedure Index), evaluates the green character of an entire analytical methodology, from sample collection to final determination, and was created using such tools as the National Environmental Methods Index (NEMI) or Analytical Eco-Scale to provide not only general but also qualitative information. In GAPI, a specific symbol with five pentagrams can be used to evaluate and quantify the environmental impact involved in each step of an analytical methodology, mainly from green through yellow to red depicting low, medium to high impact, respectively. The proposed tool was used to evaluate analytical procedures applied in the determination of biogenic amines in wine samples, and polycyclic aromatic hydrocarbon determination by EPA methods. GAPI tool not only provides an immediately perceptible perspective to the user/reader but also offers exhaustive information on evaluated procedures.

New Polymeric Materials for Solid Phase Extraction

ABSTRACT Solid phase extraction (SPE) is a popular sample preparation technique, which can be applied directly in gas–solid phase and liquid–solid phase, or indirectly to solid samples by using, e.g., thermodesorption with subsequent chromatographic analysis. Although SPE can be described as a physical extraction process involving a liquid phase and a solid phase, the increased use of packed sorbent formats seems to have led to a bias toward packed sorbent SPE devices. Without any doubt, the heart of the SPE technique is the sorbent material as it has a direct influence on the selectivity, sorptive capacity, and the format or the configuration of the resultant SPE device. There will always be a need for new sorbent materials, and therefore, it is imperative to focus research efforts on versatile sorbent fabrication techniques that could address current and anticipated challenges. Various polymeric materials have been developed and implemented in everyday life. They are also extensively used in analytical chemistry. This review provides an updated summary of the most important features of polymeric sorptive materials used at the stage of preparing samples for analysis. The application of each new polymeric sorbent material is discussed in detail. Moreover, the comparison between these materials is done.

Direct solid phase microextraction combined with gas chromatography – Mass spectrometry for the determination of biogenic amines in wine

A direct method based on immersion solid phase microextraction (DI-SPME) gas chromatography mass-spectrometry (GC-MS) was optimized and validated for the determination of 16 biogenic amines in Polish wines. In the analysis two internal standards were used: 1,7-diaminoheptane and bis-3-aminopropylamine. The method allows for simultaneous extraction and derivatization, providing a simple and fast mode of extraction and enrichment. Different parameters which affect the extraction procedure were studied and optimized including ionic strength (0-25%), fiber materials (PDMS/DVB, PDMS/DVD + OC, Polyacrylate, Carboxen/PDMS and DVB/CAR/PDMS) and timings of the extraction, derivatization and desorption processes. Validation studies confirmed the linearity, sensitivity, precision and accuracy of the method. The method was successfully applied to the analysis of 44 wine samples originating from several regions of Poland and 3 wine samples from other countries. Analysis showed that many of the samples contained all examined biogenic amines. The method, assessed using an Eco-Scale tool with satisfactory results, was found to be green in terms of hazardous chemicals and solvents usage, energy consumption and production of waste. Therefore the proposed method can be safely used in the wine industry for routine analysis of BAs in wine samples with a minimal detrimental impact on human health and the environment.

Classification of Polish wines by application of ultra-fast gas chromatography

The potential of ultra-fast gas chromatography (GC) combined with chemometric analysis for classification of wine originating from Poland according to the variety of grape used for production was investigated. A total of 44 Polish wine samples differing in the type of grape (and grape growth region) used for the production as well as parameters of the fermentation process, alcohol content, sweetness, and others which characterize wine samples were analysed. The selected features coming from ultra-fast GC analysis were subsequently used as inputs for both principal component analysis (PCA) and supervised machine learning. Using the proposed classification algorithm, it was possible to classify white and red wines according to the variety of grape used for production with a 98.7 and 98.2% accuracy, respectively. The model was characterized by good recall and area under receiver operating characteristic which was 1.000 for white wines and 0.992 for red wines. Cuveé wines (made from various types of grapes) were also successfully classified which leads to the conclusion that the proposed classification method can be used not only to differentiate between wines made from different grapes but also to detect possible adulterations, provided known; non-adulterated samples are available as a reference. The model was also used to classify wine samples based on other features, such as the geographic region in which the vineyard is situated, type of yeast used, the temperature of fermentation, sweetness, etc. In all cases, a high classification accuracy (in most cases > 90%) was achieved. The obtained results could be applied in the wine industry.

Determination of Selected Metals in Fruit Wines by Spectroscopic Techniques

Background The determination of metals in different types of food and beverages samples has drawn significant attention due to several reasons with the most important one being the nutritional and toxic effects of these elements or their compounds. The knowledge of certain elements content in wines/fruit wines is of special interest due to their toxicity in case of excessive intake and also the effect they seem to have on the organoleptic properties of wine. Results The study was focused on measuring the concentration levels of trace metals in fruit wines. Analysis of K, Ca, Fe, Zn, Cd, Mg, Pb, Sn, and Hg in so-called homemade fruit wine was carried out by AES, AAS, CV-AAS, and GF-AAS techniques. The calculated calibration curves showed good linearity range for all tested analytes (with coefficient of determination in the range from 0.989 to 0.999). The low values of the limit of detection (from 0.0031 μg/L to 0.47 mg/L) and the limit of quantification (from 0.009 μg/L to 1.41 mg/L) were obtained. Conclusions The allowed levels of metal in fruit wines are prescribed by the International Office for Grapes and Wines (OIV). The data obtained from the study area for all metals did not exceed the international limits.

Evaluation of the Impact of Storage Conditions on the Biogenic Amines Profile in Opened Wine Bottles

A survey of biogenic amine (BA) profiles in opened wine bottles has been established to monitor the level of biogenic amines (BAs) in opened bottles against time and other conditions. Bottles of red and white wine were submitted to different temperatures, stopper type (screw cap, cork), and use of vacuum devices. A total of six wines made from a variety of grapes were obtained from vineyards from regions across Poland. Dispersive liquid-liquid microextraction-gas chromatography-mass spectrometry (DLLME-GC-MS) procedure for BAs determination was validated and applied for wine sample analysis. The total content of BAs from the set of immediately opened wine samples ranged from 442 to 929 µg/L for white wines, and 669 to 2244 µg/L for red wines. The most abundant BAs in the analysed wines were histamine and putrescine. Considering the commercial availability of the analysed wines, there was no relationship between the presence of BAs in a given wine and their availability on the market. However, it was observed and confirmed by chemometric analysis that the different storage conditions employed in this experiment affect not only the BAs profile, but also the pH.

Green Chemistry in Higher Education: State of the Art, Challenges, and Future Trends

Nowadays, there is increasing interest in global sustainability, and thus, university students would like to know how human actions affect the health status of our planet. This is mainly due to their basic knowledge of problems such as global warming and greenhouse gases. Students would like to gain knowledge on how to safeguard the earth for future generations. This must involve changes in education programs at interested institutions and universities. To ensure that future generations of chemists are equipped with proper knowledge, significant efforts are needed. Thus, this article aims to present the history of green chemistry, its milestones, and ideas on how to teach this subject. A discussion of awareness in the field of green chemistry and of existing teaching materials is presented. In addition, green chemistry metrics, which should be known and used by professors and students, are described. Teaching methods for green chemistry are also given, with special attention paid to organic and analytical chemistry education.