Determination of volatile organic compounds (VOCs) in indoor work environments by solid phase microextraction-gas chromatography-mass spectrometry.

Volatile organic compounds (VOCs) are continuously emitted into the atmosphere from natural and anthropogenic sources and rapidly spread from the atmosphere to different environments. A large group of VOCs has been included in the class of air pollutants; therefore, their determination and monitoring using reliable and sensitive analytical methods represents a key aspect of health risk assessment. In this work, an untargeted approach is proposed for the evaluation of the exposure to volatile organic compounds of workers in an engine manufacturing plant by GC-MS measurements, coupled with solid-phase microextraction (SPME).

Development of a highly sensitive method based on QuEChERS and GC-MS/MS for the determination of polycyclic aromatic hydrocarbons in infant foods.

Polycyclic aromatic hydrocarbons (PAHs) are environmental contaminants that can be found in various food products, including those intended for infants. Due to their potential health risks, it is crucial to develop sensitive analytical methods for the accurate determination of PAHs in infant foods. This study describes the development and validation of a highly sensitive method for the quantification of European PAH markers, namely benzo[a]pyrene, benzo[a]anthracene, chrysene, and benzo[b]fluoranthene, using gas chromatography-tandem mass spectrometry (GC-MS/MS), in baby food samples.

How new nanotechnologies are changing the opioid analysis scenery? A comparison with classical analytical methods.

Opioids such as heroin, fentanyl, raw opium, and morphine have become a serious threat to the world population in the recent past, due to their increasing use and abuse. The detection of these drugs in biological samples is usually carried out by spectroscopic and/or chromatographic techniques, but the need for quick, sensitive, selective, and low-cost new analytical tools has pushed the development of new methods based on selective nanosensors, able to meet these requirements. Modern sensors, which utilize "next-generation" technologies like nanotechnology, have revolutionized drug detection methods, due to easiness of use, their low cost, and their high sensitivity and reliability, allowing the detection of opioids at trace levels in raw, pharmaceutical, and biological samples (e.

Multipurpose new gas chromatography column based on pillararenes functionalized with imidazolium ionic liquids.

Background: Gas chromatography is worldwide recognized as one of the most important analytical techniques, due to its high versatility and reliability. The heart of a gas chromatograph is the column, that allows analyte peak separations and, consequently, accurate qualitative and qualitative analyses. New and more efficient columns are always requested to satisfy new and challenging analytical needs.

A super-massive Neptune-sized planet.

Neptune-sized planets exhibit a wide range of compositions and densities, depending on factors related to their formation and evolution history, such as the distance from their host stars and atmospheric escape processes. They can vary from relatively low-density planets with thick hydrogen-helium atmospheres to higher-density planets with a substantial amount of water or a rocky interior with a thinner atmosphere, such as HD 95338 b (ref. ), TOI-849 b (ref.

Efficient gas chromatographic separation of xylene and other aromatic isomers by using pillar[6]arene-based stationary phase.

The separation of aromatic isomers, in particular xylene isomers, represents a big issue in chemical and petroleum industries, owing to their similar molecular sizes and boiling points. In this work, the investigation ofpillar[6]arene derivative modified by long alkyl chains (P6A-C10) as a stationary phase for high-resolution gas chromatographic (GC) separations of xylene isomers is presented. Pillar[n]arenes are a new class of macrocyclic hosts that can accommodate specific guests due to their highly symmetrical and rigid pillar architectures with π-electron rich cavities.

Chromatographic Separation of Aromatic Amine Isomers: A Solved Issue by a New Amphiphilic Pillar[6]arene Stationary Phase.

In this work, the fabrication, synthesis, and characterization of a new stationary phase based on an amphiphilic pillar[6]arene (P6A-C10-2NH) for gas chromatographic analyses are reported. The gas chromatography (GC) column prepared with P6A-C10-2NH stationary phase exhibited a medium polarity, an efficiency of 3219 plates/m, and unmatched resolving capabilities toward chloroaniline, bromoaniline, iodoaniline, and toluidine isomers. Furthermore, the P6A-C10-2NH column showed excellent repeatability with maximum relative standard deviations equal to 0.

A New Capillary Gas Chromatography Column Based on Poly(ethylene glycol) Methyl Ether-Functionalized Calix[4]arene.

In this work, a novel capillary column (C4A-mPEG) with a calixarene-based polymer stationary phase (poly(ethylene glycol) methyl ether-functionalized 4-tert-butylcalix[4]arene) was designed and used for gas chromatographic (GC) separations. The C4A-mPEG capillary column, prepared by the static coating method, showed moderate polarity and a column efficiency of 2332 plates/m, determined by 1-octanol at 120 °C. The separation features of C4A-mPEG stationary phase, resulting from its unique structure and multiple molecular recognition processes with analytes, including π-π, H-bonding, dipole-dipole, and van der Waals interactions, allowed to obtain high-resolution performances for a wide range of compounds and their isomers, especially benzaldehydes, phenols, and anilines.

High-Resolution Micro-object Separation by Rotating Magnetic Chromatography.

The development of new technologies for the separation, selection, and isolation of microparticles such as rare target cells, circulating tumor cells, cancer stem cells, and immune cells has become increasingly important in the last few years. Microparticle separation technologies are usually applied to the analysis of disease-associated cells, but these procedures often face a cell separation problem that is often insufficient for single specific cell analyses. To overcome these limitations, a highly accurate size-based microparticle separation technique, herein called "rotating magnetic chromatography", is proposed in this work.

On the use of a 2D-carbon microfiber fractionation system to improve flow-injection QTOF-HRMS analysis in complex matrices: the case of flower extracts.

A two-dimensional microscale carbon fiber/active carbon fiber system combined with a quadrupole time of flight high-resolution mass spectrometry (2DμCFs-QTOF-HRMS) system is proposed for the rapid putative identification of polar, medium-polar and weakly polar constituents in complex matrices while strongly mitigating ionic suppression effects. The capabilities of 2DμCFs-QTOF-HRMS have been proven by analysing the composition of flower extracts, allowing, in a single run, the detection of 41 known substances and the presence of 6 compounds never revealed before in these samples. 2DμCFs-QTOF-HRMS has been compared with traditional HPLC-MS, showing higher versatility and a significant reduction of both analysis time (70 min to 5 min) and solvent consumption (35 mL to 1.

Ex-situ and in-situ rapid and quantitative determination of benzene derivatives in seawater using nanoconfined liquid phase nanoextraction.

Benzene derivatives (BDs) constitute a class of environmental pollutants whose exposure poses a grave risk to human health. These compounds rapidly diffuse from the atmosphere to the marine ecosystem: for this reason, their monitoring in seawater is every day more compelling. In this work, nanoconfined liquid phase nanoextraction (NLPNE), a versatile extraction technique recently described, has been for the first time applied to the gas chromatographic mass spectrometry (GC/MS) analysis of BDs in seawater.

Essential oil characterization of Prunus spinosa L., Salvia officinalis L., Eucalyptus globulus L., Melissa officinalis L. and Mentha x piperita L. by a volatolomic approach.

In this study a volatolomic approach is proposed for the characterization of the volatile organic compound (VOC) composition of essential oils (EOs) extracted from common aromatic plants. Five species (Prunus spinosa L., Salvia officinalis L.

Data processing for fennel protein characterization by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS).

An untargeted shot-gun approach is described for the ultra-high-resolution analysis of fennel proteins by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) combined with a home-made Matlab search algorithm. The first step of the proposed bioinformatic strategy was the development of a custom-made fennel protein database, starting from the well-known, on-line available, protein NCBI database, under organism, consisting of 231 total proteins. Partial and redundant forms of proteins, repeatedly included in the official NCBI database under different codes, were removed.

Investigation of fennel protein extracts by shot-gun Fourier transform ion cyclotron resonance mass spectrometry.

A rapid shot-gun method by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) is proposed for the characterization of fennel proteins. After enzymatic digestion with trypsin, few microliters of extract were analyzed by direct infusion in positive ion mode. A custom-made non-redundant fennel-specific proteome database was derived from the well-known NCBI database; additional proteins belonging to recognized allergenic sources (celery, carrot, parsley, birch, and mugwort) were also included in our database, since patients hypersensitive to these plants could also suffer from fennel allergy.

Accurate glutamate monitoring in foodstuffs by a sensitive and interference-free glutamate oxidase based disposable amperometric biosensor.

L-Glutamate (L-Glu) is a well-known flavour enhancer that is present in several foodstuffs. Although L-Glu is generally recognized as safe, the use in foodstuffs remains controversial and then its fast and accurate monitoring represents an important issue. In this work a sensitive and interference-free disposable amperometric biosensor for glutamate monitoring in foodstuffs was developed.

Enhancing online protein isolation as intact species from soy flour samples by actively modulated two-dimensional liquid chromatography (2D-LC).

In this study, an enhanced fully automated approach is described for the protein isolation from soy flour samples by two-dimensional liquid chromatography with active modulation interface. The use of two multi-port switching valves is proposed to on-line connect the first to the second dimension column, thus overcoming the problems associated with the re-mixing effects and incompatibility of eluent composition and pH. A 5-cm long C4 analytical column installed in the interface device allows to focus the proteins coming from the first column (size exclusion chromatography), before their selective elution in the second column (reversed-phase).

Development of a screening analytical method for the determination of non-dioxin-like polychlorinated biphenyls in chicken eggs by gaschromatography and electron capture detection.

A sensitive and reproducible screening analytical method is here proposed for the determination of six non dioxin-like polychlorinated biphenyls (NDL-PCBs, congener 28, 52, 101, 138, 153, 180) in chicken eggs based on accelerated solvent extraction (ASE) procedure for the fat extraction and determination, a solid phase extraction (SPE) sample clean-up process, and a gas chromatography - electron capture detection (GC-ECD) analysis. The optimized chromatographic separation, in less than 25 min, returned good responses for the six NDL-PCBs in the range of 2.5-60.

Electrical Burns During Fruit Harvesting.

Electrocutions during tree trimming or fruit harvesting are occasionally reported in the public media, but the actual incidence is unknown. Some fruit trees (eg, mango and avocado) can exceed 30 feet, with dense foliage concealing the fruit and overlying power lines so burns associated with harvesting these fruits are often exacerbated with falls. However, there are limited data on this subject.

An automated food protein isolation approach on preparative scale by two-dimensional liquid chromatography with active modulation interface.

In this work, an automated 2D-LC approach for protein isolation from egg samples on preparative scale is proposed. The method is based on the use of a C18 guard column installed in a switching valve to focus the proteins coming from the first dimension column, before their elution in the second column. For the first dimension separation, a size-exclusion column, packed with 3 μm ultrapure silica particles was used.

Sensitive Screening Method for Determination of Pyrethroids in Chicken Eggs and Various Meat Samples by Gas Chromatography and Electron Capture Detection.

A sensitive and reproducible screening analytical method is described for the determination of six pyrethroids (phenothrin, permethrin, cyfluthrin, cypermethrin, deltamethrin, fenvalerate) in egg and meat samples by gas chromatography and electron capture detection (GC-ECD). A fast cleanup procedure, based on solid-phase extraction has been used, ensuring reduced solvent consumption and time and allowing the simultaneous preparation of multiple sample extracts. Under the optimal chromatographic conditions, an efficient separation was obtained with a total analysis time of less than 60 min, including the extraction-purification steps.

Rapid method for the quantification of 13 sulphonamides in milk by conventional high-performance liquid chromatography with diode array ultraviolet detection using a column packed with core-shell particles.

In the present study, a column packed with core-shell particles was used for the separation and the quantification of 13 sulphonamides in milk by conventional high-performance liquid chromatography coupled with diode array ultraviolet detection (HPLC/UV-DAD). Preliminary experiments were carried out to investigate selectivity of different stationary phases. Best results were achieved using a C column packed with 2.

Milk authenticity by ion-trap proteomics following multi-enzyme digestion.

The practice of adding adulterating substances in milk in order to raise profits is unfortunately worldwide. In addition, higher priced milk, coming from minor dairy species, is often illegally integrated with the lower priced cow milk. The presence of species-specific proteins, different from those declared in label, may be a serious problem for people with allergies.

Combined use of peptide ion and normalized delta scores to evaluate milk authenticity by ion-trap based proteomics coupled with error tolerant searching.

A fundamental issue in proteomics is the peptide identification by database searching and the assessment of the goodness of fit between experimental and theoretical data. Despite the different number of ways to measure the quality of search results, the definition of a scoring criterion is still highly desirable in ion-trap based proteomics. Indeed, in order to fully take advantage of a low resolution MS/MS dataset, it is essential to strike a balance between greater information capture and reduced number of incorrect peptide assignments.

Nano-LC-MS/MS for the identification of proteins trapped in sorbent cartridges used for coupled plasma filtration-adsorption treatments of healthy pigs.

A dedicated proteomic approach based on nano-Liquid Chromatography coupled with tandem mass spectrometry in ion trap is proposed for the analysis of proteins trapped in sorbent resin cartridges used to remove inflammatory mediators from blood by coupled plasma filtration adsorption (CPFA). The final purpose of the proposed proteomic approach was to obtain a reference map of plasma proteins trapped in CPFA sorbents used for the extracorporeal blood purification of healthy pigs, with the potential impact to design new bio-filters able to control the inflammatory imbalance under pathological conditions, such as severe sepsis. The five main steps of the proteomics analysis, (i) protein extraction from resin cartridges, (ii) two-dimensional gel electrophoresis (2D-PAGE) for protein separation and profiling, (iii) in-gel proteolytic digestion, (iv) tandem mass analysis of peptides resulting from enzymatic cleavage and (v) bioinformatics, for protein identification and post-processing validation of MS/MS data sets, have been carefully evaluated.