Bioprospecting of Essential Oil-Bearing Plants: Rapid Screening of Volatile Organic Compounds Using Headspace Bubble-in-Drop Single-Drop Microextraction for Gas Chromatography Analysis.

Essential oils are vital constituents of oil-bearing plants. However, their screening still demands harvesting of the plant for laboratory analysis. We report herein a simple, rapid and robust headspace bubble-in-drop microextraction screening technique (BID-SPME) requiring only small amounts of plant material.

A systematic assessment of research trends on polycyclic aromatic hydrocarbons in different environmental compartments using bibliometric parameters.

Polycyclic aromatic hydrocarbons (PAHs) are a large group of diverse hazardous organic compounds that are relatively stable and widely distributed throughout the world's ecosystems due to various anthropogenic activities. They are generally less soluble in water and have a low vapour pressure, but dissolve easily in adipose tissues; and they bioaccumulate into high concentrations in aquatic animals, thereby exerting a variety of hazardous and lethal effects. Despite the plethora of research studies on these pollutants, only few bibliometric reviews on the subject have been documented in the literature.

Application of an agitation-assisted dispersed solvent microextraction for analysis of naphthalene and its derivatives from aqueous matrices.

Agitation-assisted dispersive liquid-liquid extraction without a dispersing solvent is lately receiving considerable attention owing to the low to no solvent loss relative to its predecessor, which suffers severe extracting solvent loss. Herein, we report the application of a simple agitation-assisted dispersive liquid-liquid microextraction method, without a disperser solvent, for the extraction of naphthalene and its derivatives from aqueous solutions. Under the optimised conditions, namely, 25 μL 3:1 mixture of dichloroethane and ethylacetate with 20 s agitation, in 2-mL aqueous solutions containing 10% NaCl, the method demonstrated acceptable figures of merit: linearity-R ≥ 0.

Comparison of Soxhlet and reflux techniques for extraction and characterisation of potential endocrine-disrupting compounds from solid waste dumpsite soil.

Landfill leachate contains a myriad of hazardous chemicals; as such, they should always be planned and constructed following approved guidelines. A sample of soil collected from the old quarry designated as the official solid waste disposal site in Maseru, the capital city of Lesotho, was exposed to two extraction techniques, namely Soxhlet and reflux extractions, for characterisation of the potential endocrine-disrupting chemicals in the leachate. Principal component analysis was used to compare the extractability of these chemicals between the two methods, and it revealed that phthalates extract better in Soxhlet than in reflux extraction.

Rapid Screening of Volatile Organic Compounds from Seeds Using Headspace Solid Phase Microextraction Coupled to Gas Chromatography Mass Spectrometry.

Volatile organic compounds (VOCs) derived from plants have been used in the fragrance industry since time immemorial. Herein we report on the rapid screening of VOCs from seeds of ripe (family, Zingiberaceae) using a polydimethylsiloxane fibre headspace solid phase microextraction coupled to a gas chromatography mass spectrometry (SPME-GC/MS) instrument. Portions of 0.

Hollow-Fibre-Supported Dispersive Liquid-Liquid Microextraction for Determination of Atrazine and Triclosan in Aqueous Samples.

We report the application of the dispersive liquid-liquid microextraction coupled to hollow-fibre membrane-assisted liquid-phase microextraction and its application for extraction of atrazine and triclosan. Under optimum conditions, namely, 25 L of a 1 : 4 chlorobenzene : ethyl acetate mixture dispersed in 1 mL of aqueous sample, 10% (m/v) NaCl, a magnetic stirrer speed at 600 rpm, and 10 minutes' extraction time with toluene-filled fibre as the acceptor phase, the method demonstrates sufficient figures of merit. These include linearity ( ≥ 0.

Highlighting mass spectrometric fragmentation differences and similarities between hydroxycinnamoyl-quinic acids and hydroxycinnamoyl-isocitric acids.

Background: Plants contain a myriad of metabolites which exhibit diverse biological activities. However, in-depth analyses of these natural products with current analytical platforms remains an undisputed challenge due to the multidimensional chemo-diversity of these molecules, amplified by both isomerization and conjugation. In this study, we looked at molecules such as hydroxyl-cinnamic acids (HCAs), which are known to exist as positional and geometrical isomers conjugated to different organic acids namely quinic- and isocitric acid.

Picogram-level quantification of some growth hormones in bovine urine using mixed-solvent bubble-in-drop single drop micro-extraction.

Growth hormones are important biologically active compounds. However, they can cause deleterious effects if not used with care and their use in farmed animals is banned in the European Union. This study presents the development and application of a mixed-solvent "bubble-in-drop single drop micro-extraction" (BID-SDME) method for enrichment of stilbene hormones in bovine urine samples.

Solvent-assisted headspace sampling using solid phase microextraction for the analysis of phenols in water.

Headspace analysis is used widely and relies on volatilization of analytes into the headspace above the matrix. We detail the dramatic influence that added solvent can have on headspace analysis of phenols, without the requirement for specialized headspace vials. The use of water-immiscible solvents is key and leads to a 1-3 orders of magnitude enhancement in the volatilization of these analytes and shorter fiber exposure times than are otherwise required.

Rapid detection of atrazine and metolachlor in farm soils: gas chromatography-mass spectrometry-based analysis using the bubble-in-drop single drop microextraction enrichment method.

Tracking of metolachlor and atrazine herbicides in agricultural soils, from spraying through to harvest, was conducted using our recently reported "bubble-in-drop single-drop microextraction" method. The method showed good linearity (R(2) = 0.999 and 0.

Bubbles in solvent microextraction: the influence of intentionally introduced bubbles on extraction efficiency.

Significant improvements to microdrop extractions of triazine pesticides are realized by the intentional incorporation of an air bubble into the solvent microdroplet used in this microextraction technique. The increase is attributed partly to greater droplet surface area resulting from the air bubble being incorporated into the solvent droplet as opposed to it sitting thereon and partly to thin film phenomena. The method is useful at nanogram/liter levels (LOD 0.