Capillary Gas Chromatography Research Articles

N – alkanes in molluscs of Shatt Al-Arab river

This study comprises monitoring of the n-alkanes in the Shatt Al-Arab river by using the seven molluscs species as bioindicators. These species are: snails Lymnaea auricularia, Theodoxus jordani, Physa acuta, Melanopsis nodosa, and Melanoides tuberculata and bivalves Corbicula fluminea and Corbicula fluminalis. The species of molluscs are collected from different locations of the Shatt Al-Arab river (along the region extended from Abu Al-Khasib to Garmat-Ali) during 2004 and 2005. Each species consisted of at least 3500 adult of individuals of uniform sizes. The hydrocarbons from these species were extracted and analyzed both by spectroflurometer (total hydrocarbons) and high resolution capillary gas chromatography (n-alkanes). The concentrations of total hydrocarbons in mollusc’s species of the Shatt Al-Arab river ranged from 1.93 μg/g dry weight in T. jordani to 26.56 μg/g dry weight in C. fluminea. The range of carbon chain length of n-alkanes in these individuals was ranging from C13 - C32. The bimodal distribution with two maxima around C17 and C27 suggested two different sources of hydrocarbons both biogenic and anthropogenic. The dominance of the odd carbon numbers n-alkanes (C15, C17, C25 and C29) in the mollusc’s species indicated biogenic origin of hydrocarbons .The pristane values were more than those of phytane. Pristane and phytane in the mollusc’s species suggest biogenic origin. CPI values are more than one indicating a biogenic origin of hydrocarbons in these species. Squalane is also present in some these species intimately related to anthropogenic sources of hydrocarbons. The presence of Unresolved Complex Mixture (UCM) reflects the anthropogenic sources. The lower fat contents were found in T. jordani (0.33 mg/g) and the higher were in C. fluminea (0.98 mg/g). A significant relationship is found between the fat contents and hydrocarbons concentrations in the tissues of molluscs species (r = 0.8 - 0.9).

Organic Matter and Molecular-Weight Distribution of Hydrocarbons in the Annenskoe Thermal Waters (Far East, Russia)

Abstract —The paper presents new data on the composition of organic matter and the molecular-weight distribution of saturated hydrocarbons in the thermal waters of the Annenskoe field. The TIC chromatograms of extracts of the thermal waters, obtained by capillary gas chromatography–mass spectrometry, revealed 98 organic compounds of biogenic, thermogenic, and technogenic origin. The technogenic components amount to no more than 5%. The geochemical odd–even preference indices of saturated hydrocarbons (CPI, ACL, OEP, and TARHC) are calculated. It is shown that organic matter, in particular, saturated hydrocarbons, results from two processes: thermogenic processes in the water–rock system and bacterial activity. Variations in the composition of organic matter in the Annenskoe thermal waters have been determined for the first time. They are characterized by minor fluctuations within 30 min and serious fluctuations over two years and are expressed as an increase in the portion of thermogenic alkanes and a decrease in the portion of nitrogen-containing components.

Characterization of volatile compounds of cooked wild Iberian red deer meat extracted with solid phase microextraction and analysed by capillary gas chromatography - mass spectrometry

Wild Iberian red deer meat demand and interest are increasing and, therefore, an in-depth characterization of meat quality is needed to meet consumer demands. The objective of the present work was to assess, for the first time, the volatile profile of cooked wild sport-hunted Iberian red deer meat. Twenty-three loin samples from male red deer (Cervus elaphus hispanicus) were cooked and the volatile profile was analysed using solid phase microextraction, followed by capillary gas chromatography-mass spectrometry. Fifty-five volatile compounds were found. The major ones in number and relative abundance were aldehydes (84%), followed by alcohols (11%), hydrocarbons (2.4%), ketones (1.7%), furans (0.34%) and sulphur compounds (0.18%). Hexadecanal was the major compound and other long-chain compounds such as (E)-2-tetradecen-1-ol or 2-pentadecanone were also reported in considerable abundance. Several compounds related to grass-based diets were identified (2,3-octanedione, hexadecane or 1-pentadecanol). Odour impact ratio of volatile compounds was calculated and dimethyl trisulphide, (E,E)-2,4-decadienal, decanal and dodecanal were the most odorant compounds affecting the flavour of the cooked deer meat.

Chemical composition of phenylpropanoid rich chemotypes of Ocimum basilicum L. and their antimicrobial activities

Ocimum basilicum L., is most popular fragrant herb renowned for its immense application. However, a plethora of studies revealed terpenoids and phenylpropanoids as marker chemicals with known identities. We herein report two unique chemotypes developed in CSIR-CIMAP for their compositional variability and biological activities. Essential oils obtained from aerial parts of both the chemotypes were analyzed in capillary gas chromatography and mass spectrometry systems on 5% diphenyl- and cyclodextrin coated fused silica columns. The statistical analysis was carried out to validate the phytochemical data of consecutive years and also to calculate the variability. The phenylpropanoids dominated the volatile fractions of chemotype II (72.5–77.5%) in comparison to chemotype I (29.8–40.0%) essential oil. In the contrary, sesquiterpenoids (16.4–17.4%) and monoterpenoids (33.5–43.9%) contributed oil composition of chemotype I in diverse proportions. The presence of single images of R-(+)-camphor and R-(-)-linalool were established in both the oils analyzed on a ethyl substituted cyclodextrin-based column. Essential oils were tested for biological activities against C. albicans, S. aureus, and E. coli. meta-Eugenol, the marker compound isolated from chemotype I showed best inhibition against C. albicans. In conclusion, meta-eugenol-rich chemotype I with high essential oil yield (0.1–0.8%) was identified as an alternative source for meta-eugenol.

Configurations and Sensory Properties of the Stereoisomers of 2,6-Dimethyl-4-propyl-1,3-oxathiane and 2,4-Dimethyl-6-propyl-1,3-oxathiane.

The heterocyclic compounds 2,6-dimethyl-4-propyl-1,3-oxathiane 1 and 2,4-dimethyl-6-propyl-1,3-oxathiane 2 were obtained by condensing 4-mercapto-2-heptanol and 2-mercapto-4-heptanol, respectively, with acetaldehyde. For both, separation of the eight stereoisomers was achieved via capillary gas chromatography using heptakis(diethyl-tert-butyldimethylsilyl)-β-cyclodextrin as the chiral stationary phase. Their configurations were assigned by combinations of enzyme-catalyzed kinetic resolutions, HPLC separations, and assessments of NMR data. The odor thresholds and odor qualities of the stereoisomers were determined by capillary gas chromatography/olfactometry. The odor thresholds of the stereoisomers of 2 were generally higher than those of 1. For both oxathianes, the stereoisomers in which all substituents are in equatorial positions showed the highest odor thresholds. Most of the stereoisomers of 1 exhibited pleasant flowery, fruity, or sweet nuances; the stereoisomers of 2 were mainly characterized by descriptors, such as broth, mushroom, or pungent. The data demonstrate the impact of the positions of substituents and their spatial orientations on the sensory properties of 1,3-oxathianes.

Trans fatty acids in frequently consumed products from Serbian and Slovenian market.

Industrially produced trans fatty acid (iTFA) have adverse health effects and thus their consumption should be limited. The aim of this study was to determine and compare the iTFA content in frequently consumed food products by young adults from the Serbian and Slovenian market with supposedly elevated iTFA content in 2015. At the time of this study, there was no recommended limit of iTFA in both countries, and reduction of iTFA in foods was on voluntary basis. We determined iTFA content in food products, 19 from the Serbian and 22 from the Slovenian market, blinded and analysed in the same analytical run. Contents of fatty acids (FA) methyl esters were analysed by capillary gas chromatography with a flame ionisation detector. Heptadecanoic acid was used as internal standard. Individual FA along with TFA were expressed as percentages of total measured FA. The amount of each FA in the sample was then calculated from the response factor and the transformation factor of the FA from the FA methyl ester content. Elaidic acid (C18:1t) was found as the most abundant TFA in analysed products, ranging from 0.52 g/100 g of total FA in chocolate candy up to 60.4 g/100 g in a salami from Serbian market. In Slovenian products, the values for elaidic acid were lower, 0.04-3.95 g/100 g of total FA, except in one type of wafers (24.3 g/100 g). The majority of analysed products from the Serbian and three from Slovenian market exceeded the recommended WHO and EU limit of 2% iTFA of total fat in foods. Samples of frequently consumed salami, wafers, tea biscuits, and snacks were identified as products with potentially higher burden of iTFA in diets of young adults in Serbia.

Performance and selectivity of amphiphilic pillar[5]arene as stationary phase for capillary gas chromatography

Pillar[n]arenes possess highly symmetrical and rigid pillar-shaped architecture with π-electron rich cavity that afford their reliable host-guest recognition interactions towards matched guests. In this work, a novel amphiphilic pillar[5]arene (P5A-C10-2NH2) was designed, synthesized and employed as the stationary phase for capillary gas chromatography. To date, they have not been reported in the field of chromatography. The P5A-C10-2NH2 capillary column (10 m × 0.25 mm i.d.) was prepared by static coating method. Its capillary column exhibited moderate polarity and column efficiency of 2265 plates/m determined by naphthalene at 120 °C. As evidenced, the P5A-C10-2NH2 column achieved advantageous separation performance for a mixture of 24 analytes of diverse types and exhibited different chromatographic selectivity from two pillar[5]arene derivatives columns and commercial HP-35 column with 35%-phenyl-methylpolysiloxane. Moreover, the P5A-C10-2NH2 column baseline resolved more than a dozen positional and cis-trans isomers. Furthermore, the separation mechanism of P5A-C10-2NH2 column was discussed by quantum chemical calculations. In addition, the P5A-C10-2NH2 column had high thermal stability and excellent separation repeatability 0.01–0.04% for run-to-run, 0.03–0.17% for day-to-day and 3.2–3.9% for column-to-column. The special amphiphilic structure and high resolution for various analytes reveal the good potential of pillararenes as a new class of stationary phases for chromatographic analyses. Moreover, the TPG column achieved improved thermal stability over the GIL column and excellent repeatability.

Is Golay’s Famous Equation for HETP Still Relevant in Capillary Gas Chromatography? Part 2: Assumptions and Consequences

This installment is the second part of a discussion on the origins and uses for determining the height equivalent of a theoretical plate (HETP) calculations in gas chromatography (GC). This month, I discuss the good and challenging consequences of the Golay theory, its relevance, and some alternatives. Many of the variables that chromatographers view as independent have some interdependence, and we see several limitations of the theory. The complex relationships between HETP and temperature present a particular challenge when thinking about temperature-programmed GC compared to isothermal GC. This article concludes with comments regarding the continued relevance of this classical theory.

Eco-friendly bioremediation approach for crude oil-polluted soils using a novel and biostimulated Enterobacter hormaechei ODB H32 strain

Petroleum oil contaminants have become severe ecological problems and negatively impact human health. It is, therefore, imperative to identify environmentally friendly approaches to remediate oil-polluted environments. Therefore, bacterial oil degradation stimulated with a nitrogen source under optimum conditions was assessed in this study. Based on the 16S rRNA analysis, strain ODB H32 recovered from oil-based mud of some petroleum drilling sites in the western desert, Egypt, was identified as Enterobacter hormaechei. The metabolic fingerprint of E. hormaechei, achieved using BIOLOG GEN III, revealed that the strain could utilize diverse carbon and chemical sources. Also, E. hormaechei could biodegrade 0.6% of oil under optimized pH (7.0) and temperature (30 °C) conditions. Analyzing different nitrogen stimulants revealed that peptone ˃ yeast extract ˃ ammonium nitrate ˃ urea enhanced the growth of E. hormaechei on mineral salts medium (MSM). Analysis by capillary gas chromatography revealed maximum (70.7%) degradation of peptone by E. hormaechei, indicating that peptone was a good biostimulant for oil degradation. These findings recommend using biostimulated E. hormaechei as an eco-friendly approach for remediating oil-polluted environments, under optimized conditions, especially in arid regions like the western desert of Egypt.

Is Golay’s Famous Equation for HETP Still Relevant in Capillary Gas Chromatography? Part 1: A Common View of HETP

In this installment of “GC Connections,” we take a close look at Golay’s famous equation that most people view as relating to height equivalent to a theoretical plate (HETP) to the carrier gas flow rate or average linear gas velocity in a capillary column. We explore the original works of Golay and Keulemans. We also look closely at the original equation, the assumptions involved with its development, and the assumptions (both good and bad) that have been applied to HETP over the years. In part two, we will explore the consequences and relevance of this theory today, with temperature programming, very long (and very short) columns, high pressure drops, and vacuum outlet detectors.

Quantitative Organic Acids in Urine by Two-Dimensional Gas Chromatography-Time-of-Flight Mass Spectrometry (GCxGC-TOFMS).

Seventy-six organic acids in urine specimens are determined with quantitative two-dimensional gas chromatography-time-of-flight mass spectrometry (GCxGC-TOFMS). The specimen is treated with urease to remove urea and then derivatized to form pentafluorobenzyl oximes (PFBO) of oxo-acids. The sample is then treated with ethyl alcohol to precipitate proteins and centrifuged. After drying the supernatant, the organic acids are derivatized to form volatile trimethylsilyl (TMS) derivatives for separation by capillary two-dimensional gas chromatography (GCxGC) with temperature programming and modulation. Detection is by time-of-flight mass spectrometry (TOFMS) with identification of the organic acids by their mass spectra. Organic acids are quantitated by peak areas of reconstructed ion chromatograms with internal standards and calibration curves. Organic acids are quantified to determine abnormal patterns for the diagnosis of more than 100 inherited disorders of organic acid metabolism. Characteristic abnormal metabolites are quantified to monitor dietary and other modes of treatment for patients who are diagnosed with specific organic acid disorders.

Substantiation of technological parameters of the oil extract obtained from Urtica dioica roots based on the yield determination of phytosterols using capillary gas chromatography method

Due to the content of phytosterols, extractive preparations of Urtica dioica roots are able to show antiandrogenic effect in the case of external therapy of men and women with androgenic alopecia. Oil extracts (OE) are characterized by several advantages when applied to the skin of the scalp compared to water-alcohol extracts. For the development of OE technology from Urtica dioica roots, it is important to choose the optimal extraction parameters, which are based on the quantitative determination of phytosterols in the extractant and the studied samples of extracts.
 The aim of the work is to choose the optimal parameters for obtaining OE from Urtica dioica roots based on quantitative determination of phytosterols content in experimental samples of OE by gas capillary chromatography.
 Materials and methods. Objects of the research – Urtica dioica root, refined corn oil, refined sunflower oil, samples of oil extracts. Determination of phytosterol content in experimental samples was carried out by gas capillary chromatography (chromatograph “Crystal 2000”, manufacturer – research and production company “Analytics”).
 Results. 5 different compounds of steroid structure (stigmasterol, β-sitosterol, etc.) were identified in sunflower oil by gas liquid chromatography, and 10 (campesterol, 2-α stigmasterol, β-sitosterol, Δ5-avenosterol, etc.) were identified in sunflower oil. The quantitative content of β-sitosterol in the sum of sterols of corn oil was significantly higher compared to the content of this substance in sunflower oil and amounted to 59.33 %. Optimal technological parameters were established considering the peculiarities of extraction with oil extractant and quantitative determination of the amount of phytosterols and β-sitosterol in experimental samples of OE. The total content of plant sterols in OE, including considering their amount in the extractant, was in the range of 7880 mg/kg; the amount of β-sitosterol was 4638 mg/kg.
 Conclusion. The choice of optimal parameters for obtaining OE from UDR based on determination of phytosterol yield by gas capillary chromatography was experimentally substantiated, namely: extractant – corn oil, raw material-extract ratio – 1: 5, extraction time – 6 h, extraction method – maceration

Chemotaxonomy of Five South American Species of the Triatoma genus (Hemiptera: Reduviidae: Triatominae) Based on Their Cuticle Hydrocarbon Pattern.

The Triatoma sordida subcomplex traditionally included four triatomine species, T. sordida, Triatoma garciabesi, Triatoma guasayana, and Triatoma patagonica, distributed in the Southern Cone of South America. These species have a large intraspecific variability together with an overall similarity, making difficult to establish their taxonomic status. Many cytogenetic, morphometric, and molecular markers have been applied to address this. Recent studies have posed concerns on the inclusion of T. guasayana and T. patagonica within the subcomplex. Also, T. sordida from Argentina has been designed as a new species, Triatoma rosai. Using the cuticular hydrocarbon pattern as chemotaxonomic marker, the relationships among several populations of these species were analyzed by capillary gas chromatography and linear discriminant analysis along 25 collection sites in Argentina, Bolivia, Brazil, and Paraguay. T. sordida and T. rosai populations were differentially clustered in two CHC-based groups: "Group 1" included T. sordida from Eastern Brazil, Eastern Paraguay, and the Bolivian populations from La Paz and Izozog G1; "Group 2" included T. rosai, and T. sordida from Izozog G2 (Bolivia), and Western Paraguay. Whereas T. garciabesi remained closely related to T. sordida and T. rosai, T. guasayana, and T. patagonica were clearly separated from the species of the T. sordida subcomplex. Our results agree with those from other several techniques suggesting that the taxonomy of the T. sordida subcomplex should be revised.

THE BOUILLON TABLES FROM TURKEY: DETERMINATON OF CIS-TRANS FATTY ACID PROFILES BY CAPILLARY GAS CHROMATOGRAPHY

Nowadays, commmercial bouillon tablets are mostly used as a flavor enhancer substant or an instant product in Turkish cuisine. As chemical structure, Trans FAs are unsaturated fatty acids having at least one double bond in its trans geometric configuration. Trans FA are occured by the partial hydrogenation of vegetable oils in the manufacturing of margarine and vegetable shortening. In this study, industrially produced commmercial bouillon tablet (n=14) samples from Turkey were analyzed by capillary (DB 23 column) gas chromatography method and an under controlled temperature oven programm with particular emphasis on cis–trans fatty acid profiles. The bouillon samples were collected as two goups (first group containing animal additives [AAB n=12] and second group including vegatable additives [VAB n=2]). There is no detailed information on fatty acid (FA) compounds, including trans fatty acids (TFAs), of consumed several commercial boullions in Turkey. There is no “trans fatty acid-free” declaration on various bouillon labels in Turkey. Large variations were observed among the cis–trans FA profiles of the boullion samples from Turkey,despite the fact that the samples are produced in the same production conditions.The palmitic (PAM) levels (predominant cis saturated FAs for all samples) of AAB samples (32.63–44.44%) were more high rather than the VAB samples (47.62–50.64%). Other major saturated FAs for AAB and VAB samples were determined stearic ( (5.28–9.90% AAB and 6.33–6.73% VAB), lauric (0.19– 5.84% AAB and 1.13–1.30% VAB) and myristic acids (0.86–2.61% AAB and 1.39–1.45% VAB).The changes of oleic (OLA) acid (from other predominant cis monounsaturated FA) of VAB samples (30.75–33.45%) were high than those of AABs (12.64–29.35%). The ranges of LO, an essential /nutritional fatty acid and the predominant FA of PUFAs, and PUFAs of AAB – except two samples– commercial bouillon samples (0.45–9.82% and 0.45–9.97% ) were low rather than VAA samples (7.97–8.14% and 8.14–8.35 %). Conjugated Linoleic (CLA) FAs, having nutritional FAs having anti-carcinogenic, antioxidative and anti-atherosclerotic effects, were determined in small amounts for only six samples (0.03% to 0.06% ). Elaidic acid (C18:1 trans acid) content, the mainly trans FA in all boullion, was within the range of 20.00–27.32% in the AAB samples, and it was significantly higher than the range in VAB samples (0.08–0.14%). Total trans fatty acids (TFAs) were another important major (second) FAs for all bouillon samples. The changes of Trans/Cis ratio ranged between 0.26 and 0.50 for AAB samples but VB samples has a little values from 0.002 to 0.003. Turkish vegetable boullion. samples have low total trans FA contents (0.19–0.26%) than the animal boullion samples (20.19–28.78%).There are a large variation and significant (P<0.05) differences were statistically determined among major cis FAs (PAM, SA, OLA, LO and LN) and their involved parameters (SFAs, MUFAs and PUFAs). The consumed several commercial boullions in Turkey were classified and characterized chemometric method (Principal Component Analysis, PCA) based on some fatty acid profiles and their parameters. Applying PCA to the all bouillon samples data determined the percentage of total variance explained by the first two PCs were 49.3% and 21.8% (totally 71.1%), respectively.

A Rapid Method for the determination of Dehydrated alcohol (Ethanol) content in Clobetasol propionate foam by Non-polar Capillary Gas chromatography

Clobeatsol propionate foam is a topical class 1 corticosteroid used to treat itching and inflammatory arthritis on the skin occurred by allergic reactions, psoriasis and eczema. In the pharmaceutical aerosol products, Dehydrated alcohol (Ethanol) is the primary ingredient and its concentration level in the formulation composition plays a significant role in the regulation of aerosol rate, droplet shape and particle size. It can also act as solubilizer for active pharmaceutical ingredient, topical disinfectant and skin permeation enhancer. Hence accurate assay of Ethanol is a crucial quality control component. A simple and rapid gas chromatography method was developed to quantify Ethanol content in Clobetasol propionate foam drug product using fused silica glass tube non-polar capillary column (HP-5, 30 m, 0.53 mm, 1.5 µm). Ethanol in the sample was diluted with methanol after adding suitable amount of internal standard, the isopropyl alcohol solution.The developed method is precise, linear and accurate in the range of 5 mg/mL to 15 mg/mL of nominal concentration of ethanol i.e. 10 mg/mL . The presented method has an advantage of a very quick gas chromatographic separation (less than 16 min) and therefore is highly suitable for in-process and stability analysis of Ethanol content in Clobetasol propionate foam drug product.

Sulfolane as a novel stationary phase for analytical separations by gas chromatography

Sulfolane is explored as a novel stationary phase for use in analytical separations by capillary column gas chromatography with flame ionization detection (GC-FID). Stainless steel capillaries were found to provide a good substrate for coating and retaining a sulfolane phase, whereas fused silica tubing did not perform well for this. In general, the phase was found to be stable for several hours of use when using elevated carrier gas pressures (90 psi) and a small restriction (25 μm I.D. tubing) at the outlet. This normally provided good performance at temperatures up to about 200 °C with very little background interference in the FID. Given its separation properties, a short 2 m × 100 μm I.D. column was found to be preferable for most separations in this study. Measurements indicated the coating procedure yielded a sulfolane film near 4 μm thick on this column, which produced 4400 plates for benzene with a sample capacity near 30 μg. The sulfolane phase yielded good retention and peak shape for many analytes including alkanes, aromatics, alcohols, bases, sulfides, phosphites, thiols, and others. Compared to longer conventional GC columns, the relatively short sulfolane column was found to offer improved selectivity in the separation of unsaturated, aromatic, and alkane test analytes. As such the method was successfully applied to the analysis of aromatics in gasoline headspace. Results suggest that sulfolane could be a potentially useful stationary phase to further explore in GC separations.

Immunological and genetic indices in workers under long-term exposure to low-doses of acrylonitrile

Introduction. Nowadays there is very relevant research on the study of the characteristics of the impact on the health of workers of low levels of harmful factors (acrylonitrile) of production during long-term exposure. Aim of the study was to examine peculiarities of immunologic and genetic indices in workers under the long-term exposure to acrylonitrile in low doses. Materials and methods. Our research object was working area air (MPCw.ar.=0.5 mg/m3) and biological media (blood and exhaled air) of workers employed at industrial rubber manufacture. Acrylonitrile was determined via a non-invasive procedure in exhaled air with samples being concentrated on sorption tubes that were then analyzed with capillary gas chromatography. Blood samples were examined to determine contents of malonic dialdehyde, lymphocytes (absolute and relative activated T-lymphocytes CD3+CD25+, absolute and relative activated T-lymphocytes CD3+CD95+), cytokines (VEGF), oncomarkers (PSA), and adrenals hormones; to do that, we applied ELISA tests and flow cytometry. Results. Acrylonitrile was established to occur in working area air in concentrations varying within MPCw.ar. range (0.007-0.015 mg/m3) being 2-3 times higher than in air inside offices at the same enterprise. We obtained statistically significant linear dependence between concentrations of acrylonitrile in the air exhaled by workers (y) and their working experience (x) that was given with the following equation: y=0.00046+0.00027x. According to the results of the laboratory examination of the workers, violations of the antioxidant defense were established. Contents of malonic dialdehyde and steroid hormones including progesterone, estradiol, and hydrocortisone that were pathogenetically linked to each other were authentically up to 3.2 times higher in the test group than in the reference one (p<0.05). Risk for antioxidant protection disorders such as elevated malonic dialdehyde contents in blood plasma might occur in the test group was 1.58 times higher than in the reference one. Conclusion. We revealed certain peculiarities in polymorphism of PPARGC1A Gly482Ser rs8192678 gene, the variability of which contributes to the formation of pathology of the cardiovascular, endocrine systems, oncoproliferative states that increase the likelihood of these undesirable events.

Trietyloamina. Metoda oznaczania w powietrzu na stanowiskach pracy z zastosowaniem chromatografii gazowej z detekcją płomieniowo-jonizacyjną

Triethylamine (TEA) is a tertiary aliphatic amine. At room temperature it is a colourless liquid with a strong ammonia odor. TEA is used as a substrat in production of quaternary ammonium compound, as a catalyst in polymerization process, as a solvent in organic synthesis and as an emulsifier in the production of dyes and pesticides. Occupational exposure to TEA can cause many adverse effects like skin, respiratory tract or eye irritation. TEA may cause also vision disorder like blurred vision or red-blue vision. The aim of this study was to develop and validate a method for determining TEA in workplace air. The developed method is based on the collection of TEA on sorbent tube filed with two sections of silica gel coated with hydrochloric acid. Silica gel is extracted with methanol:water mixture and resulted solution is analysed with capillary gas chromatography with flame-ionization detector. The study was performed using gas chromatograph equipped with DB-5ms column. The developed method is linear in the concentration range of 7.5–150 μg/ml, which is equivalent to the range of 0.03–6 mg/m3 for 100-L air sample. The analytical method described in this paper makes it possible to determine TEA in workplace air in the presence of other substances. The method is precise, accurate and it meets the criteria for procedures for determining chemical agents listed in Standard No. PN-EN 482. The developed method for determining TEA in workplace air has been recorded as an analytical procedure (see Appendix). This article discusses the problems of occupational safety and health, which are covered by health sciences and environmental engineering.

A selective and inert stationary phase combining triptycene with tocopheryl polyethylene glycol succinate for capillary gas chromatography

This work reports a selective and inert triptycene-based stationary phase (TPT) combining the triptycene framework with tocopheryl polyethylene glycol succinate (TPGS) units for capillary gas chromatography (GC). The TPT stationary phase was physically coated onto a capillary column by static coating method with the column efficiency of 4200 plates/m and moderate polarity. As demonstrated, the TPT column exhibited high inertness towards organic bases, including basic heterocycles, aliphatic and aromatic amines, showing distinct advantages over the TPGS and commercial columns. Also, the TPT column displayed high-resolution performance towards the isomers of methylpyridines, toluidines, xylidines and alkanes (C6–C8). Moreover, it showed excellent separation repeatability and reproducibility with RSD values in the range of 0.03%-0.07% for run-to-run, 0.12%–0.18% for day-to-day and 2.3%–3.6% for column-to- column (n = 4). Its applications to purity test of chemical products and to GC-MS analysis of the essential oil of Artemisia annua L. demonstrated its good potential for practical analyses. The present work has novelty in constructing highly selective and inert stationary phases and providing a feasible strategy for concurrently addressing the related problems in GC analyses. Its methodology and findings is of important value in terms of fundamental researches and practical applications.

Phytochemical profiling of spiny coriander (Eryngium foetidum L.) – A potential perennial spicing-culinary herb of eastern India

Abstract Spiny coriander (Eryngium foetidum L.) is a perennial medicinal herb grown in the tropical regions worldwide. In India, it is used as a potential spice for garnishing and flavoring the dishes and treating several ailments. Eryngium spp. found in coastal Odisha, India has a strong aroma similar to the seasonal Coriandrum. The volatile flavor constituents of the unique plants were analyzed through headspace solid-phase microextraction (HS-SPME) using capillary gas chromatography (GC) and gas chromatography-tandem mass spectrometry (GC–MS/MS). The volatile compounds exhibited high chemodiversity, with 10-undecenal as the major component in leaves (44.98%) and branches (57.43%). Fourier-transform infrared (FTIR) spectroscopy identified eight major peaks grouped into six main regions. Chemo profiles of these two corianders were overlapped and showed similar area differences in the spectral peak. The lesser-known perennial Eryngium with high chemodiversity would be a better alternative to the seasonal coriander for aromatic, pharmaceutical, and industrial uses.