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A solid-phase microextraction method coupled with a flame photometric detector was developed for the analysis of organophosphorus pesticides in water. Two kinds of fiber (100 μm polydimethyl siloxane (PDMS) and 85 μm polyacrylate (PA) fibers) were used and compared. Parameters that may affect the extraction, such as the duration of absorption and desorption, temperature of absorption, ionic strength,...
Solid-phase microextraction presents numerous advantages over traditional extraction techniques. However, the determination of partition coefficients is not as simple as it may appear. For very nonpolar compounds, such as polycyclic aromatic compounds, adsorption to the glass wall of the extraction vial and the Teflon coating of the stir bar may be quite significant. These interactions must be taken...
Ultrasonic solvent extraction combined with solid-phase microextraction (SPME) with calix[4]arene/hydroxy-terminated silicone (C[4]/OH-TSO) oil coated fiber was used to extract phthalate acid esters (PAEs) plasticizers in plastic, such as blood bags, transfusion tubing, food packaging bag, and mineral water bottle for analysis by gas chromatography (GC). Both extraction parameters (i.e. extraction...
Extraction of dry cured ham volatile compounds by solid-phase microextraction (SPME) was optimized. Different fiber coatings (carboxen/polydimethylsiloxane (CAR/PDMS), divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS), polydimethylsiloxane (PDMS), polydimethylsiloxane/divinylbenzene (PDMS/DVB)), times of extraction (15, 30, 60min) and sample preparation (ground samples and homogenates with...
Solid-phase microextraction (SPME) coupled with high-performance liquid chromatography (HPLC) for the determination of triazine is described. Carbowax/templated resin (CW/TPR, 50μm), polydimethylsiloxane/divinylbenzene (PDMS/DVB, 60μm), polydimethylsiloxane (PDMS, 100μm), and polyacrylate (PA, 85μm) fibers were evaluated for extraction of the triazines. CW/TPR and PDMS/DVB fibers were selected for...
A method for the determination of the earthy and musty odors geosmin, 2-methylisoborneol (2-MIB), 2-isobutyl-3-methoxy pyrazine (IBMP), 2-isopropyl-3-methoxy pyrazine (IPMP) and 2,4,6-trichloroanisole (2,4,6-TCA) in water by headspace solid-phase microextraction (HSSPME) combined with gas chromatography–ion trap mass spectrometry (GC–ITMS) is described. Several parameters of the extraction and desorption...
A new solid-phase microextraction (SPME) fiber has been developed and applied for the determination of some amines (n-pentylamine, tripropylamine, dibutylamine, diisobutylamine and tributylamine). In this study two copper wires were immersed in sodium chloride solution and electrolysis was performed at a constant potential. Anode was oxidized to copper(I) to produce copper(I) chloride as a sorbent...
HS-SPME–GC–MS in combination with PCA was employed to discriminate different arabica/robusta blends having different geographical origins. HS-SPME confirmed to be an effective and reproducible sampling technique for routine characterization of coffees. In addition, the chemometric approach permitted to find parameters suitable for the differentiation of the different blends and the determination of...
A novel laboratory-made sol–gel calix[4]arene/hydroxy-terminated silicone oil coated fiber has been applied for headspace solid-phase microextraction (HS-SPME) combined with gas chromatography (GC) with electron capture detection (ECD) to determine 12 organochlorine pesticides (OCPs) and their metabolites in radish sample. The analytes in the study consisted of α-, β-, γ- and δ-hexachlorocyclohexane...
Volatile compounds of grapes are responsible of varietal aroma. At the moment, methods used for analysis of these compounds are solvent-based, time-consuming and generally require large amounts of sample. In order to obtain an appropriate technique to study grape volatile compounds, HS-SPME method has been developed. The optimal sampling conditions were: 70°C for 20min with a 65-μm PDMS/DVB fibre...
A new method is presented for the determination of DMA in water as its 9-fluorenylmethyl chloroformate (FMOC) derivative using solid-phase microextraction (SPME) and liquid chromatography. The method is based on the employment of SPME fibres coated with carbowax-templated resin (CW-TR) for analyte extraction and derivatization. The fibres were successively immersed in the samples, in a solution of...
A sensitive method for determination of ephedrine derivatives using headspace solid-phase microextraction (SPME) with a novel fiber followed by capillary electrophoresis has been developed. The co-poly(butyl methacrylate/hydroxy-terminated silicone oil) (BMA/OH-TSO) was used as stationary phases with the aid of γ-methacryloxypropyltrimethoxysilane (KH-570) as bridge in SPME using sol–gel-coating method...
This work describes a new approach for the determination of trimethylamine (TMA) in water and air by liquid chromatography (LC). The assay is based on the employment of a solid-phase microextraction (SPME) fiber for sampling and for derivatization of the analyte with the fluorogenic reagent 9-fluorenylmethyl chloroformate (FMOC). The fiber, with a Carbowax-templated resin −50μm coating, was first...
The volatile composition of aniseed-flavoured spirit drinks was studied by headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS). The influence of the time, temperature, volume of sample and ionic strength on the extraction were considered. Several aniseed-flavoured spirit drinks, such as pastis, sambuca, anis and raki were analyzed. The major compounds...
An integrated method of combining solid-phase microextraction (SPME) with liquid chromatography–mass spectrometry (LC–MS) was evaluated for determination trace amount of sulfonamides in meat products. Eight commonly used sulfonamides, sulfadiazine (SDZ), sulfathiazole (STZ), sulfamerazine (SMR), sulfamethazine (SMT), sulfamonomethoxine (SMMX), sulfamethoxazole (SMXZ), sulfaquinoxaline (SQX) and sulfadimethoxine...
This paper investigates the detection of 2,3-dimethyl-2,3-dinitrobutane (DMNB), a marking agent in explosives, by gas chromatography (GC) with electron capture detection using solid-phase microextraction (SPME) as a sample preparation technique. The 25,27-dihydroxy-26,28-oxy (2′,7′-dioxo-3′,6′-diazaoctyl) oxy-p-tert-butylcalix[4]arene/hydroxy-terminated silicone oil coated fiber was highly sensitive...
A direct immersion solid-phase microextraction coupled with gas chromatography-electron capture detection (SPME-GC-ECD) method was optimized and validated for the quantitative determination of 18 organochlorine pesticides in ground water. Ionic strength, stirring speed, adsorption and desorption time and pH were some of the parameters investigated in order to select the optimum conditions for SPME...
This work combines the utilization of the micellar media during the extraction step and the focused microwave-assisted extraction followed by the solid-phase microextraction–gas chromatography/mass spectrometry (SPME–GC/MS) to determine the alkyl- and methoxy-phenolic content in wood extractives. The proposed environmental-friendly method is mainly characterized by short analysis times (5min for the...
A simple, sensitive, and accurate method for determination of polybrominated diphenyl ethers (PBDEs) in soil has been developed based on headspace solid-phase microextraction (HS-SPME) followed by gas chromatography–mass spectrometry (GC–MS). Permethylated-β-cyclodextrin/hydroxyl-termination silicone oil (PM-β-CD/OH-TSO) fiber was first prepared by sol–gel technology and employed in SPME procedure...
The volatile composition from four types of multifloral Portuguese (produced in Madeira Island) honeys was investigated by a suitable analytical procedure based on dynamic headspace solid-phase microextraction (HS-SPME) followed by thermal desorption gas chromatography–quadrupole mass spectrometry detection (GC–qMS). The performance of five commercially available SPME fibres: 100μm polydimethylsiloxane,...
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