Space Solid Phase Microextraction Research Articles

Urinary naphthalene and phenanthrene as biomarkers of occupational exposure to polycyclic aromatic hydrocarbons

Objectives: The study investigated the utility of unmetabolised naphthalene (Nap) and phenanthrene (Phe) in urine as surrogates for exposures to mixtures of polycyclic aromatic hydrocarbons (PAHs). Methods: The report included...

Determination of furan by headspace solid-phase microextraction–gas chromatography–mass spectrometry in balsamic vinegars of Modena (Italy)

An isotope dilution method for quantification of furan by internal standardization was adopted, using head space solid phase microextraction (HS-SPME) technique, to evaluate various samples of “aceto balsamico di Modena” (ABM), in order to verify if this seasoning may contribute to the intake of furans in the human diet. Matrix-matched calibration curves were adopted, and furan levels in the majority of the samples purchased on the Italian market ranged between 4 and 26 ng/g. Considering that furan levels in ABM derive from the heat-concentrated must of grapes and from the additive caramel E 150d often used in the production technology, the level of furan in the concentrated must appears, in some samples, not to be the only important factor affecting the risk assessment of furan linked to the use of ABM.

A Comparison of Results Obtained Using Liquid Injection and Headspace Solid-Phase Microextraction for Crude Oil Analysis by GC with Mass Spectrometer Detection

Gas chromatographic (GC) analysis in solution and head space solid-phase microextraction (SPME)-GC analysis of a sample of crude oil gave different results. The SPME technique allowed the identification of a larger number of components than by using usual GC-mass spectrometry (MS). The method failed within the range of C14-C25 where GC-MS in solution allowed to obtain more representative results; on the contrary, SPME allowed to obtain data on the presence of volatile compounds that can not be identified in GC-MS analysis in solution. Furthermore, in the range C8-C12, SPME allowed to identify approximately 30 compounds not shown in the GC-MS analysis in solution. SPME analysis showed the presence of some alkenes not identified in GC-MS analysis in solution. SPME-GC-MS can be used in the analysis of crude oil in contaminated soil.

Genetic Diversity of Volatile Components in Xinjiang Wild Apple ( Malus sieversii)

To evaluate genetic relationships using qualitative and/or quantitative differentiation of volatile components in Xinjiang Wild Apple ( Malus sieversii (Lebed.) Roem.) and to acquire basic data for the conservation and utilization of the species, aroma components in ripe fruit of M. sieversii obtained from 30 seedlings at Mohe, Gongliu County, Xinjiang Autonomic Region, China, and in ripe fruit of 4 M. pumila cultivars (‘Ralls’, ‘Delicious’, ‘Golden Delicious’, and ‘Fuji’) were analyzed using head space-solid phase microextraction and gas chromatography-mass spectrometry. The results indicated that the values of similarity coefficient concerning volatile types between the two species were in accordance with the evolution of M. pumila cultivars (forms), and that M. sieversii seedlings showed considerable genetic variations in these aspects: the total content of volatile components, the classes and contents of each compound classes, the segregation ratio, and content of main components. The results showed significant difference among seedlings and wide genetic diversity within the populations. Comparison of the volatile components in M. sieversii with those in M. pumila cultivars showed that the common compounds whose number were larger than five with the contents over 0.04 mg/L simultaneously between M. sieversii and M. pumila cultivars belonged to esters, alcohols, aldehydes or ketones. This suggests fundamental identity in main volatile components of M. sieversii and M. pumila cultivars. The results above sustained the conclusion “ M. sieversii is probably the ancestor of M. pumila”. However, there were 48 compounds present in M. pumila that were not detected in M. sieversii, including 6 character impact components (i.e., propyl acetate, (Z)-3-hexenal, 2-methyl-1-butanol acetate, pentyl acetate, 3-furanmethanol, and benzene acetaldehyde). This suggested that in the domestication of M. pumila, introgression of other apple species, except for M. sieversii, by interspecies hybridization was possible. There were 177 compounds in total belonging to 11 classes detected in 30 M. sieversii seedlings, including esters, alcohols, ketones, aldehydes, acids, benzene ramifications, terpenes, heterocycles, hydrocarbon derivates, acetals, and lactones. Among them, acetals and lactones were not detected in M. pumila cultivars, 90 compounds were unique to M. sieversii, and 7 components (1-butanol, ethyl butanoate, 1-hexanol, ethyl hexanoate, 3-octen-1-ol, ethyl octanoate, and damascenone) belonged to character impact odors. Thus, the potential of M. sieversii in “utilization conservation” is enormous as a rare germplasm on genetic improvement of M. pumila cultivars.

Solid phase microextraction and gas chromatography with ion trap detector (GC-ITD) analysis of amitraz residues in beeswax after hydrolysis to 2,4-dimethylaniline

An analytical method for the determination of amitraz residues in beeswax after hydrolysis to 2,4-dimethylaniline is reported. It consists of wax extraction with an acid buffer solution, head space solid phase microextraction and GC-ITD analysis. The limit of determination is 1 ng g −1. Wax samples from beekepers and commercial foundations were analysed, content of residues varied from <1 to 20.5 ng g −1.

A REVIEW OF MANGO FRUIT AROMA VOLATILE COMPOUNDS - STATE OF THE ART RESEARCH

Flavour is comprised of aroma and taste. This paper presents an overview on the fundamental and applied aspects of aroma volatile production in mango fruit with emphasis on the effects of chilling injury and controlled atmosphere (CA) storage. In mango fruit, more than 285 different aroma volatile compounds have been reported which include 7 acids, 55 alcohols, 31 aldehydes, 26 ketones, 14 lactones, 74 esters, 69 hydrocarbons, and 9 other compounds. Aroma volatile compounds have been reported to be influenced by various factors including the mango species, cultivars, location, fruit maturity at harvest, processing, storage and ripening conditions. This review will focus on the effects of various pre and postharvest factors, which regulate aroma volatile production. Our research group have identified sixty one aroma volatile compounds from the 'Kensington Pride' mango fruit pulp, using a head space solid phase microextraction (SPME) technique with gas chromatography (GC) and GC combined with mass spectrophotometry (GC-MS). Low temperatures during storage induced chilling injury and reduced the production of aroma volatile compounds during fruit ripening and in fully ripe fruits. The composition of CA storage as well as storage period affected production of aroma volatile compounds in the pulp of the ripe 'Kensington Pride' and 'Delta R2E2' mangoes.

Dose Related Absorption of JP-8 Jet Fuel Hydrocarbons Through Porcine Skin with Quantitative Structure Permeability Relationship Analysis

The effects of dosage on the percutaneous absorption of jet fuel hydrocarbons is not clear, yet is essential for human risk assessment. The present study is an ongoing approach to assess the dose-related percutaneous absorption of a number of aliphatic and aromatic hydrocarbons. The first treatment (1X) was comprised of mixtures containing undecane (4.1%), dodecane (4.7%), tridecane (4.4%), tetradecane (3%), pentadecane (1.6%), naphthalene (1.1%), and dimethyl naphthalene (1.3% of jet fuels) in hexadecane solvent using porcine skin flow through diffusion cell. Other treatments (n = 4 cells) were 2X and 5X concentrations. Perfusate samples were analyzed with gas chromatography-flame ionization detector (GC-FID) using head space solid phase micro-extraction fiber technique. We have standardized the assay to have a good linear correlation for all the tested components in media standards. Absorption parameters including diffusivity, permeability, steady state flux, and percent dose absorbed were estimated for all the tested hydrocarbons. This approach provides a baseline to access component interactions among themselves and with the diluent (solvents). A quantitative structure permeability relationship (QSPR) model was derived to predict the permeability of unknown jet fuel hydrocarbons in this solvent system by using their physicochemical parameters. Our findings suggested a dose related increase in absorption for naphthalene and dimethyl naphthalene (DMN).

Simultaneous detection of some drugs of abuse in saliva samples by SPME technique

A simple method for the simultaneous determination of many drugs of abuse in saliva is referred [methadone, 2-ethyl-1,5-dimethyl-3,3-diphenylpyrrolinium perchlorate (EDDP), cocaine, cocaethylene, amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyethyl amphetamine (MDEA), N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB), cannabidiol (CBD), Δ 9-tetrahydrocannabinol (THC), cannabinol (CBN)]. Head space-solid phase microextraction (HS-SPME) and direct immersion-solid phase microextraction (DI-SPME) followed by gas chromatographic/mass spectrometric analyses (GC/MS) were employed, and results obtained with both techniques are discussed. The method was validated testing reproducibility, sensitivity, linearity.

Determination of polycyclic aromatic hydrocarbons in urine of coke oven workers by headspace solid phase microextraction and gas chromatography–mass spectrometry

Polycyclic aromatic hydrocarbons (PAHs) represent a complex mixture of toxic compounds that are ubiquitous in the environment. We investigated the utility of head space-solid phase microextraction (HS-SPME) to measure the following surrogate PAHs in urine: naphthalene (NAP), phenanthrene (PHE), pyrene (PYR), and benzo(a)pyrene (BAP), representing classes of 2-, 3-, 4- and 5-ring compounds, respectively. We then applied the method to urine from 28 coke oven workers (median levels (μg/l) were: NAP=3.65, PHE=1.51, PYR=0.003, BAP not detected) and 22 controls (median (μg/l) NAP=0.859, PHE=0.062, PYR=0.001, BAP not detected). Urinary levels of NAP, PHE, and PYR were all associated with exposure category (controls, side- and bottom-workers, and top-workers) but not with smoking status. Strong correlations were observed between urinary levels of NAP, PHE, and PYR in coke-oven workers. Our results indicate that unmetabolized 2-, 3- and 4-ring PAHs can be measured in urine by HS-SPME. Such measurements can be used to investigate the uptake and metabolism of complex PAH mixtures in humans.

Statistical Analyses on the Essential Oil of Italian Coriander (Coriandrum sativum L.) Fruits of Different Ages and Origins

Thirty-one samples of Coriandrum sativum L. fruits, of different origin, year of cultivation (harvest) and crop management systems were subjected to volatile component analysis by combining Head Space Solid Phase Microextraction (HS-SPME) with GC/MS. In order to determine the importance of the major sources of volatile variability, some statistical analyses, including Cluster Analysis (CA) and Principal Component Analysis (PCA), were performed on the obtained data. The compounds, which gave the main contribution to the partition and classification of the original data, were α-pinene, p-cymene, γ-terpinene and linalool. The age of the fruits, which ranged from 1–16 years, seemed to generate rather identifiable effects such as a decreasing trend on α- and γ-terpinene, terpinolene and linalool, and an increase in p-cymene. The same components also seemed to vary depending upon the geographic location of the cultivation. No statistically relevant differences were detected between the biological and conventional cropping management techniques.

Rapid analysis of malathion in blood using head space-solid phase microextraction and selected ion monitoring

A simple and rapid method for analysis of malathion in blood was developed using head space-solid phase microextraction (HS-SPME) and gas chromatography mass spectrometry/ electron impact ionization-selected ion monitoring (GC-MS/EI-SIM). A vial containing a blood sample, ammonium sulphate, sulphuric acid and fenitrothion as an internal standard, was heated at 90 °C for 15 min. The extraction fiber of the SPME was exposed for 5 min in the head space of the vial. The compounds absorbed on the fiber were detached by exposing the fibre in the injection port of GC-MS. A straight calibration curve was obtained between malathion concentrations of 2.5 to 50.0 μg g −1 in blood. No interfering substances were found, and the time for analysis was 40 min for one sample.

Rapid analysis of amphetamines in blood using head space-solid phase microextraction and selected ion monitoring

A simple and rapid method for analysis of methamphetamine (MA) and amphetamine (AP) in blood was developed using head space-solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry/electron impact ionization-selected ion monitoring (GC-MS/EI-SIM). A vial containing a blood sample, sodium hydroxide, and pentadeuterated methamphetamine as an internal standard, was heated at 80 °C for 20 min. The extraction fiber of the SPME was exposed for 5 min in the head space of the vial. First, heptafluorobutyric anhydride solution was injected into the injection port of the GC-MS to make heptafluorobutyramide (HFB) derivatives of amphetamines, and compounds absorbed on the fiber were detached by exposing the fiber in the injection port. Straight calibration curves of MA and AP were obtained from 0.01 to 2 μg/g in blood, respectively. No interfering substances were found, and the time for analysis was 30 min for one sample.

Detection of amphetamines in urine using head space-solid phase microextraction and chemical ionization selected ion monitoring

An accurate, simple and rapid method for qualitative and quantitative analysis of amphetamine and methamphetamine in urine was developed using head space-solid phase microextraction and gas chromatography-mass spectrometry/chemical ionization selected ion monitoring. A vial containing a urine sample potassium carbonate and pentadeuterated methamphetamine which was used as an internal standard was heated at 80 °C for 20 min. The needle of a solid phase microextraction device was passed through the septum, and the extraction fiber in the needle was exposed for 5 min in the head space of the vial. The needle was removed from the vial and inserted into the injection port of gas chromatograph or gas chromatograph/mass spectrometer. The compounds adsorbed on the fiber were detached by exposing the fiber in the injection port, and analyzed. The proposed method was more than 20 times more sensitive than the conventional head space method.

A multi internal standard calibration approach for the automated and robust analysis of wine volatiles by headspace Solid Phase Microextraction and further Gas Chromatography-Mass Spectrometry

Head space solid phase microextraction (HS-SPME) is a solvent-free technique that allows an almost complete automatization and getting amazing sensitivities. The hidden risk of SPME lies in the fact that as the amount of analyte extracted is very low; it is extremely sensitive to any experimental parameter that may affect the liquid-gas and gas-solid distribution coefficients. Our aims are to measure the relative weight of these factors on the lack of accuracy, and to design a robust calibration system able to avoid or limit their effects.For the first goal, synthetic but real-like wines containing a fixed amount of selected analytes (70) and variable amounts of ethanol, non-volatile constituents and major volatile constituents were prepared following a 3-Factor complete Factorial design. The study of the relevance of the Factors carried out by analysis of variance (ANOVA) and by Principal Component Analysis revealed that the levels of major volatile constituents affected the extraction of most analytes, while ethanol and matrix affected particularly low volatile compounds. Lipophilic esters are most influenced by major volatile compounds, while acids, phenols and lactones are affected by the non-volatile matrix.13 different internal standard compounds belonging to different chemical classes were used in the calibration experiment. This was similar to the aforementioned experiment, but including as well 5 different concentration levels. In 29 out of 65 cases, a single internal standard provided a robust calibration guaranteeing an accuracy better than 10%, while in others a Partial Least Square Regression analysis was run in order to find a model able to provide maxima accuracy. Satisfactory models in terms of precision, linearity and recovery could be built for 30 other compounds, so that the method can quantify up to 59 relevant wine volatile compounds.