Injection Port Of Gas Chromatograph Research Articles

Needle extraction device for rapid and quantitative gas chromatographic determination of volatile chlorinated hydrocarbons and benzene in soil

A rapid and quantitative analytical method for volatile chlorinated hydrocarbons and benzene, such as chloroethylene, dichloromethane, and carbon tetrachloride, in soil samples was developed using a needle-type extraction device packed with activated carbon-based adsorbents. The soil sample of 10 g was placed in a glass cartridge and fixed with quartz wool to make sure not to move during the extraction process. After the internal standard solution was spiked into the soil sample, the cartridge was sealed with a polytetrafluoroethylene adapter, and the needle extraction device was used to collect the headspace gas. Analytes were purged from the soil sample and collected on the adsorbent, while pure nitrogen gas was introduced to the soil sample during the sample collection. The sampling time was approximately 10 min for 100 mL of gas sampling. After the sampling process, the extraction needle was directly inserted into a heated injection port of gas chromatography equipped with flame ionization detector (GC-FID) or that hyphenated to mass spectrometry (GC–MS). The extracted VOCs were thermally desorbed and simultaneously introduced to a GC capillary column for subsequent separation and determination. The limit of detection and limit of quantification of all the examined analytes was less than 20 and 60 ng/10 g soil in GC-FID and less than 2.5 and 7.5 ng/10 g soil in the case of GC–MS. Linear calibration curves were obtained up to 10 μg/10 g soil for all the analytes. The relative standard deviations of the ratio of analyte peak area and internal standard peak area were less than 10%. The recovery and sensitivity of analytes confirmed in the proposed method were compared with that obtained with a standard method conventionally employed.

Fatty acid profiling in animal feeds and related food matrixes using a fast GC/MS method and in situ derivatization

Fatty acid determination is used for the characterization of the lipid fraction in foods, providing essential information regarding feed and food quality. Most edible fats and oils are composed primarily of linear saturated fatty acids, branched, mono-unsaturated, di-unsaturated, and higher unsaturated fatty acids. To attain this information we developed a gas chromatography (GC) method that can separate fatty acids from C4 to C24 using mass spectrometry identification. A simplified sample preparation procedure was applied so it is not time-consuming and short enough to avoid fat degradation. Additionally, one-step derivatization was applied to obtained fatty acid methyl esters in situ in the gas chromatograph injection port, using tetramethylammonium hydroxide and a high polarity polyethylene glycol-based cross-linked microbore chromatographic column was coupled to achieve the separation of 60 compounds in under 15 minutes with extreme sensibility. The versatility of the method allows fatty acid profile (including saturated [SFA], monounsaturated [MUFA], and polyunsaturated fatty acids [PUFA]) information to be gathered in different products of primary production i. raw materials commonly used in the production of animal feed, ii. profiles for balanced feed for laying hens, beef cattle and dairy cattle and iii. products of animal origin intended for human consumption, such as meat, eggs, and milk. Our data (performance parameters and fatty acid profiles) support the validity of the results; the method can be used for quality assurance both in productive species feed and feed ingredients, pet food, and related food matrices. The technique presented herein can be used as a high-throughput routine screening tool to assess fat quality as this data is paramount to improve animal nutrition and health and animal-derived products of human consumption.

Direct thermal desorption technique as a very fast, easy and low‐cost method for analysis of volatile components compounds by gas chromatography with mass spectrometry

AbstractIn medicinal plants, mass spectrometry with gas chromatography has an effective application to the determination as well as quantification of essential oil components. Nevertheless, since the excessively long period is required for sample preparation, the efficiency is restricted. The purpose of this study was to optimize a novel direct thermal desorption procedure coupled with mass spectrometry and gas chromatography for identification and semi‐quantification of volatile components in the medicinal plant samples. A direct thermal desorption mass spectrometry with gas chromatography technique has been employed to determine volatile components of a medicinal plant. The mentioned technique was used for desorption of volatile components of Stachys inflata Benth in the gas chromatography injection port. In this approach, only a dry sample of 2 mg is required for obtaining results. The results have indicated the identification and quantification more than 35 volatile compounds for Stachys inflata Benth. All obtained results indicate that the current approach is a successful instrument for high‐speed analysis of volatile components of plants. Furthermore, there are good correlations between the volatile components constituent determined by direct thermal desorption technique and conventional hydrodistillation method. The results indicated that the direct thermal desorption technique is a fast, simple, low‐cost, highly efficient and solvent‐free extraction approach.

Vacuum-assisted sorbent extraction: An analytical methodology for the determination of ultraviolet filters in environmental samples

Vacuum-assisted sorbent extraction (VASE) has been applied in combination with gas chromatography-mass spectrometry for the determination of UV filters in water samples. VASE is a variant of headspace extraction which was developed in conjunction with the sorbent pen (SP) technology. This technique combines the advantages of both stir-bar assisted extraction and headspace solid-phase microextraction. The SP traps allowed both reduced pressure in-vial extraction and direct thermal desorption via a unique gas chromatographic injection port. The main parameters that affect the performance of VASE, including both extraction and desorption conditions, were extensively optimized. Under optimum conditions, extraction required 10 mL of sample within 40 mL vials, pH 3.5, ~30 s of air-evacuation, 14 h incubation at 70 °C, stirring at 200 rpm, and a final water management step conducted at ~ −17 °C for 15 min. Optimal thermal desorption required preheating at 260 °C for 2 min followed by desorption at 300 °C for 2 min. The beneficial effect of reduced-pressure extraction was demonstrated by comparing the UV filter extraction time profiles collected using VASE to an analogous atmospheric pressure procedure, resulting in up to a 3-fold improvement under optimized conditions. The VASE methodology enabled simultaneous extractions using different SPs without compromising the method reproducibility, which increases the overall sample throughput. The method was characterized by low limits of detection, from 0.5 to 80 ng L−1, and adequate reproducibility, with inter-SP and inter-day relative standard deviation lower than 14%. Tap and lake water was successfully analyzed with the proposed methodology, resulting in relative recoveries of spiked samples ranging between 70.0 and 120%.

Direkt Daldırma Katı Faz Mikroekstraksiyon Yöntemi İle Kiraz Örneklerinde Klorpirifos Kalıntılarının Gaz Kromatografisi Kütle Spektrometresinde Tayini

A method based on a solid phase microextraction gas chromatography- mass spectrometry (SPME-GC/MS) was developed for the quantitative determination of chlorpyrifos residues in cherry samples. Three kinds of fiber coatings: PA (polyacrylate, 85µm), PDMS–DVB (polydimethylsiloxane–divinylbenzene 65 mm) and PDMS (polydimethylsiloxane, 100 mm) were compared. Various parameters affecting SPME procedures such as temperature, extraction and desorption times, salinity, stirring rate were investigated. The analytes from all sample extracts were preconcentrated for 30 minutes in the SPME fiber at 60 °C and then the fiber was desorbed by heating at 250 °C for 10 minutes in the gas chromatography injection port. Limits of detection (LOD) and quantitation (LOQ) values were 0.03 µg/L and 0,1 µg/L, respectively. An average recovery range was 93-98% with relative standard deviation (RSD) < 10 %.

Concentration determination of urinary metabolites of N,N-dimethylacetamide by high-performance liquid chromatography-tandem mass spectrometry.

Objectives: N,N-Dimethylacetamide (DMAC) is widely used in industry as a solvent. It can be absorbed through human skin. Therefore, it is necessary to determine exposure to DMAC via biological monitoring. However, the precision of traditional gas chromatography (GC) is low due to the thermal decomposition of metabolites in the high-temperature GC injection port. To overcome this problem, we have developed a new method for the simultaneous separation and quantification of urinary DMAC metabolites using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Methods: Urine samples were diluted 10-fold in formic acid, and 1-μl aliquots were injected into the LC-MS/MS equipment. A C18 reverse-phase Octa Decyl Silyl (ODS) column was used as the analytical column, and the mobile phase consisted of a mixture of methanol and aqueous formic acid solution. Results: Urinary concentrations of DMAC and its known metabolites (N-hydroxymethyl-N-methylacetamide (DMAC-OH), N-methylacetamide (NMAC), and S- (acetamidomethyl) mercapturic acid (AMMA) ) were determined in a single run. The dynamic ranges of the calibration curves were 0.05-5 mg/l (r≥0.999) for all four compounds. The limits of detection for DMAC, DMAC-OH, NMAC, and AMMA in urine were 0.04, 0.02, 0.05, and 0.02 mg/l, respectively. Within-run accuracies were 96.5%-109.6% with relative standard deviations of precision being 3.43%-10.31%. Conclusions: The results demonstrated that the proposed method could successfully quantify low concentrations of DMAC and its metabolites with high precision. Hence, this method is useful for evaluating DMAC exposure. In addition, this method can be used to examine metabolite behaviors in human bodies after exposure and to select appropriate biomarkers.

Coiled wire filament sample introduction for gas chromatography–mass spectrometry

A simple device based on a tiny, coiled wire filament (CWF), similar in operation to solid phase microextraction (SPME), was reported almost a decade ago for sampling, concentrating, and minimizing contamination for Injection of liquid samples in gas chromatography (GC). However, the pliability of the platinum wire from which the CWF was fabricated was a hindrance when using this technique. In this work, we utilized a much stiffer stainless steel wire to form the CWF, and explored a number of ways to use it for sampling and sample introduction in GC and GC–MS. The coil radius and number of turns in the CWF (i.e., length of the coil) determined the sampling volume. The CWF was attached to a retractable plunger (part of a hand-held syringe-type holder) such that it could be retracted inside a 19G needle for insertion into a standard GC injection port. Sampling was easily performed by either dipping the CWF in a liquid sample (i.e., sample dissolved in a solvent), which was drawn up into the wire coil by capillary action, or by applying a specific volume of liquid sample onto the CWF using a micro-syringe. Analytes trapped in/on the CWF could be introduced into the GC injection port before or after solvent evaporation. For semi-volatile compounds, the sample solvent was evaporated before injection, while for volatile compounds, some or all of the sample solvent was retained in the coil during injection. Repeatable volumes from 0.05 to 0.7μL were sampled using CWFs with 5–70 turns, respectively, when sampling by dipping. Advantages of using a CWF compared to a conventional syringe include: (1) the chromatographic system is protected from contamination caused by accumulation of sample residues, (2) high quantitative repeatability is obtained for small volume injections (0.05–0.2μL), (3) large sample injections can be performed for trace analysis by evaporating the solvent before injection, and (4) carryover and discrimination of semi-volatile compounds are minimized. These advantages enable easy and rapid (10min total analysis time) trace (0.1–5ppb) detection of a variety of different types of compounds, including polycyclic aromatic hydrocarbons, biphenyl congeners, organochlorine pesticides, pyrethroid pesticides, phthalate esters, and n-alkanes from C10 to C40 in water and waste water.

A novel needle trap device with nanoporous silica aerogel packed for sampling and analysis of volatile aldehyde compounds in air

In this study a needle trap device (NTD) packed with nanoporous silica aerogel (NPSA) was developed as a rapid determination technique for formaldehyde and acrolein in air. The performance of NTD-NPSA, which was characterized using several analytical figures of merit including linearity, repeatability, recovery, limit of detection (LOD), and limit of quantification (LOQ), was then compared to NIOSH 2541 method. The LOD and LOQ of NTD-NPSA for the two compounds were 0.01–0.02μgL−1 and 0.033–0.068μgL−1, respectively. The intra and inter-day relative standard deviation of method were 3.6–6.9% and 5.1–9.4%, respectively. The result of this comparative study showed that NTD-NPSA had a better performance than the NIOSH 2541 method. Unlike the NIOSH 2541method, the NTD-NPSA is a solvent-free technique, in which the desorption of the analyte is directly performed thermally inside the gas chromatograph injection port. The fact that NTD-NPSA does not require a solvent and, also, the reusability of the technique can reduce the total sampling costs for the procedure compared with costs for solvent-based sampling and extraction methods. Thus, this technique is a reliable and effective method for the determination of aldehyde in both indoor and outdoor environments.

Prototype of an Interface for Hyphenating Distillation with Gas Chromatography and Mass Spectrometry.

Chemical analysis of complex matrices-containing hundreds of compounds-is challenging. Two-dimensional separation techniques provide an efficient way to reduce complexity of mixtures analyzed by mass spectrometry (MS). For example, gasoline is a mixture of numerous compounds, which can be fractionated by distillation techniques. However, coupling conventional distillation with other separations as well as MS is not straightforward. We have established an automatic system for online coupling of simple microscale distillation with gas chromatography (GC) and electron ionization MS. The developed system incorporates an interface between the distillation condenser and the injector of a fused silica capillary GC column. Development of this multidimensional separation (distillation-GC-MS) was preceded by a series of preliminary off-line experiments. In the developed technique, the components with different boiling points are fractionated and instantly analyzed by GC-MS. The obtained data sets illustrate dynamics of the distillation process. An important advantage of the distillation-GC-MS technique is that raw samples can directly be analyzed without removal of the non-volatile matrix residues that could contaminate the GC injection port and the column. Distilling the samples immediately before the injection to the GC column may reduce possible matrix effects-especially in the early phase of separation, when molecules with different volatilities co-migrate. It can also reduce losses of highly volatile components (during fraction collection and transfer). The two separation steps are partly orthogonal, what can slightly increase selectivity of the entire analysis.

Environmentally friendly solid-phase microextraction coupled with gas chromatography and mass spectrometry for the determination of biogenic amines in fish samples.

In this work, a facile and environmentally friendly solid-phase microextraction assay based on on-fiber derivatization coupled with gas chromatography and mass spectrometry was developed for determining four nonvolatile index biogenic amines (putrescine, cadaverine, histamine, and tyramine) in fish samples. In the assay, the fiber was firstly dipped into a solution with isobutyl chloroformate as derivatization reagent and isooctane as extraction solvent. Thus, a thin organic liquid membrane coating was developed. Then the modified fiber was immersed into sample solution to extract four important bioamines. Afterwards, the fiber was directly inserted into gas chromatography injection port for thermal desorption. 1,7-Diaminoheptane was employed as internal standard reagent for quantification of the targets. The limits of detection of the method were 2.98-45.3 μg/kg. The proposed method was successfully applied to the detection of bioamines in several fish samples with recoveries ranging 78.9-110%. The organic reagent used for extraction was as few as microliter that can greatly reduce the harm to manipulator and environment. Moreover, the extraction procedures were very simple without concentration and elution procedures, which can greatly simplify the pretreatment process. The assay can be extended to the in situ screening of other pollutant in food safety by changing the derivatization reagent.

Extraction of Citrus paradisi Volatile Components by Headspace Single-Drop Microextraction and Statistical Modeling.

In present study, headspace single-drop microextraction (HS-SDME) was applied for the extraction and preconcentration of the volatile components of the plant sample into a microdrop surface. The extraction occurred by suspending a microliter drop of the solvent from the tip of a microsyringe to the headspace of a ripe fruit sample (grapefruit Citrus paradisi) in a sealed vial for a preset extraction time. Then the microdrop was retracted back into the microsyringe and injected directly into a gas chromatography injection port. The chemical composition of the SDME extracts was confirmed according to their mass spectra, and quantitative analysis was performed by gas chromatography-flame ionization detector (GC-FID). Response surface methodology along with Box-Behnken design was applied to optimize the extraction condition of four components, d-limonene, β-myrcene, α-pinene and β-pinene, from the peel of grapefruit. Parameters considered for SDME include the kind of the extracting solvent, size of drop, extraction temperature and extraction time. The optimized condition was microdrop volume of 1 µL, extraction time of 2 min and sample temperature of 50°C.

Measurement of mercury species in whole blood using speciated isotope dilution methodology integrated with microwave-enhanced solubilization and spike equilibration, headspace-solid-phase microextraction, and GC-ICP-MS analysis.

A biomonitoring method was developed for the determination of inorganic-, methyl-, and ethylmercury (Hg(2+), CH3Hg(+), and C2H5Hg(+), respectively) in whole blood by triple-spiking speciated isotope dilution mass spectrometry (SIDMS) using headspace (HS) solid-phase microextraction (SPME) in combination with gas chromatographic (GC) separation and inductively coupled plasma mass spectrometric (ICP-MS) detection. After spiking the blood sample with isotopically enriched analogues of the analytes ((199)Hg(2+), CH3(200)Hg(+) and C2H5(201)Hg(+)), the endogenous Hg species were solubilized in 2.0 mol L(-1) HNO3 and equilibrated with the spikes using a microwave-enhanced protocol. The microwaved sample was treated with a 1% (w/v) aqueous solution of sodium tetrapropylborate (buffered to pH 5.2), and the propylated Hg species were sampled in the HS using a Carboxen/polydimethylsiloxane-coated SPME fiber. The extracted species were thermally desorbed from the fiber in the GC injection port and determined by GC-ICP-MS. The analytes were quantified, with simultaneous correction for their method-induced transformation, on the basis of the mathematical relationship in triple-spiking SIDMS. The method was validated using a bovine blood standard reference material (SRM 966, Level 2). Analysis of human blood samples demonstrated the accuracy and reproducibility of the method, which can detect the Hg species down to 30 pg g(-1) in blood. The validity of the analytical results found for the blood samples was demonstrated using mass balance by comparing the sum of the concentrations of the individual Hg species with the total Hg in the corresponding samples; the latter was determined by isotope dilution mass spectrometry (IDMS) after decomposing the blood using EPA Method 3052 with single-spiking.

Needle-type Extraction Device Designed for Rapid and Sensitive Analysis in Gas Chromatography

A needle-type extraction device is one of the promising sample preparation devices for the gas chromatographic (GC) analysis of various organic compounds. The most remarkable advantage of this device is a simple and rapid desorption of the analytes by direct insertion of an extraction needle into a conventional GC injection port. In this review, fundamental aspects of the needle-type extraction devices and its applications for the determination of trace organic compounds, especially volatile organic compounds (VOCs), in several sample matrices are described.

Reduction of matrix effects in pesticide residue analysis in food by programmable temperature vaporizer

Background: The phenomenon known as the “matrix-induced chromatographic response enhancement” commonly affects the sensibility, precision, and accuracy in pesticide residue analysis. The presence of matrix effects can be given by adsorption and/or thermal decomposition of pesticides on the gas chromatograph injection port. Objective: To reduce the matrix-induced chromatographic response enhancement on pesticide residues analysis in food through the use of several operational modes of programmable temperature vaporizer inlet. Methods: The analyses were carried out in potato (Solanum tuberosum) extracts by gas chromatography with mass spectrometry detector. In this study, four programmable temperature vaporizer splitless modes were investigated: hot, pulsed, cold and solvent vent. Another topic developed in this study has to do with the influence of injection volume, assessed for the matrix effects. Results: The analysis of variance (ANOVA) (α = 0.05) indicates that when the hot splitless is used most compounds are subjected to matrix-induced chromatographic response enhancement. Furthermore, with the pulsed splitless, a decrease in the number of compounds with matrix-induced chromatographic response enhancement was found, approximately 20% compared to the classic hot splitless. Finally, a remarkable decrease in matrix-induced effects was found when cold splitless mode was used, since there was up to 55% reduction in the compounds, relative to traditional hot splitless, that showed statistical differences between responses in matrix-free standards and matrix-matched standards. Conclusions: It was found that the use of conventional hot splitless and pulsed splitless modes caused matrix-induced effects in more than 70% of the studied compounds. In addition, the results indicate that for most compounds there is an inverse relationship between matrix-induced chromatographic response enhancement and the volume of injection.

GC–MS volatolomic approach to study the antimicrobial activity of the antarctic bacterium Pseudoalteromonas sp. TB41

Many bacteria produce a wide range of volatile info-chemicals compounds (mVOCs) that constitute an important regulatory factor in the interrelationships among different organisms in microbial ecosystems. It has been shown that Antarctic bacteria isolated from three different sponge species, by producing mVOCs, are able to inhibit specifically the growth of Burkholderia cepacia complex (Bcc) strains (i.e. opportunistic pathogens of cystic fibrosis patients) as demonstrated by cross-streaking inhibition assays. This study reports a metabolomics approach to investigate the volatile profile of both the Antarctic sponge-associated Pseudoalteromonas sp. TB41 (P-sp-TB41) and Burkholderia cenocepacia strain LMG16654 (Bc-LMG16654) under aerobic conditions. Solid phase micro extraction (SPME) in head space of biological samples allowed an in vivo sampling of mVOCs with minimal specimen disturbance. The SPME fiber was termically desorbed in the injection port of gas chromatography–mass spectrometer (GC–MS) system setted in EI scan mode. The raw data were processed using both an automated mass spectra deconvolution and identification system and a metabolomic approach, which allowed a selection of 30 compounds presumably responsible for the inhibition of Bc-LMG16654 growth. The results obtained from samples prepared under cross-streaking conditions also suggest that the presence of Bc-LMG16654 cells neither interferes with the production of mVOCs nor induces the synthesis of different mVOCs. The employing of mass spectrometry played a key role in tuning the experimental system and in the evaluation of results. The use of this approach to study the interaction, in aerobic condition, among other Antarctic bacteria and Bcc and the possibility to extend this approach to other pathogen-antagonist relationship, is currently in progress.

Sample Preparation of Volatile Organic Compounds with Needle−Type Extraction Device

Needle−type extraction devices have been developed for the simple andsensitive determination of gaseous volatile organic compounds (VOCs) in gas chromatography (GC). The needle−type extraction device allows direct insertionoftheextraction medium into the GC injection port, therefore, simple and rapid desorption of the extracted analytes could be achieved. For simultaneous derivatization and preconcentration of VOCs, fiber−packed needle was developed. The fiber−packed needle was prepared with a bundle of fine filaments typically coated with methyl−polysiloxane. During the extraction, target analytes, such as volatile aldehydes or ethylene oxide, were simultaneously derivatized and concentrated in the extraction needle.Particle−packed needle has been developed for the extraction of VOCs commonly found in environmental gaseous samples. Several particulate materials, such as porous polymer particles or activated carbon, were employed as the extraction media for the respective target analytes. The particle−packed extraction needle was successfully appliedforvarious analytical situations, such as in−door air analysis, fire investigation and human breath analysis.

Partial conversion of methanol to formaldehyde in the gas chromatography injection port and reactivity with amines

The partial conversion of methanol (MeOH) to formaldehyde (HCHO) in the gas chromatograph (GC) injection port was studied. The presence of formaldehyde in the injection port can result in reaction with injected analytes, especially primary and secondary amines. A systematic study of this problem was undertaken using norephedrine and ephedrine as probe analytes, and experiments involving varying inlet temperature, comparisons among solvents and solvent mixtures, isotopic labeling, and formaldehyde spiking. These experiments showed a direct correlation between inlet temperature and formation of the amine–formaldehyde condensation products. The mass spectra of the norephedrine and ephedrine condensation products were consistent with addition of the methylene group derived from formaldehyde across the amine and alcohol moieties to form the corresponding oxazolidine-ring compounds. Results for the imine condensation product of didesmethylsibutramine formed in the injection port are also presented.

Determination of perfluorocarboxylic acids in water by ion-pair dispersive liquid–liquid microextraction and gas chromatography–tandem mass spectrometry with injection port derivatization

A novel technique for derivatization in a gas chromatograph injection port after a one-step extraction of trace perfluorocarboxylic acids (PFCAs) in water with ion pair formation during dispersive liquid–liquid microextraction (DLLME) was investigated. Tetrabutylammonium hydrogen sulfate (TBAHS) was used as the ion pair reagent. PFCA butyl ester derivatives were formed in the GC injection port and then analyzed using gas chromatography coupled to tandem mass spectrometry with negative chemical ionization. According to our analysis, the operative linear range for PFCA detection from 250pgmL−1 to 2μgmL−1 with a relative standard derivation (RSD) below 13%. Detection limits were achieved at the level of 37–51pgmL−1. This method was successfully applied for the analyzing of PFCAs in river water samples from urban and industrial areas without tedious pretreatment. The concentration range over which PFCAs were detected is from 0.6ngmL−1 to 604.9ngmL−1.

Rapid Screening Method for the Total Petroleum Hydrocarbons in Water Samples by Solid-Phase Microextraction and GC-MS

Determination of total petroleum hydrocarbons (TPH) in water is an important tool for monitoring of contamination due to oil spills or leaking storage tanks. In this study, a screening method for the quantification of total petroleum hydrocarbons in water based on solid phase microextraction (SPME) in combination with gas chromatography – mass spectrometry (GC-MS) is presented. Extraction of hydrocarbons from water samples were conducted by SPME fiber coating placed into the headspace above water. Petroleum hydrocarbons were desorbed from the fiber coating in the injection port of gas chromatograph. The effect of the following parameters affecting the distribution of the analytes between three phases on the response of TPH were studied: SPME fiber coating type and dimensions, extraction temperature, extraction time and pH. The optimized method uses 100 μm polydimethylsiloxane fiber coating, extraction time 600 s, extraction temperature 80 °C, without addition of salt at basic pH. The developed method was successfully applied for detection of total petroleum hydrocarbons in water taken from Koschagyl oil fields and Koschagyl village.

Simple Analysis of Naphthalene, Fluorene, and Anthracene in Whole Blood by Gas Chromatography/Mass Spectrometry After Headspace-Solid Phase Microextraction

A simple and sensitive method for the simultaneous analysis of naphthalene, fluorene, and anthracene in whole blood was developed using headspace-solid-phase microextraction (SPME) and GC/MS. A 0.5 g whole blood sample, 5 microL naphthalene, fluorene, and anthracene (50 microg/mL) as spiked standards, and 0.5 mL sodium hydroxide were placed into a 12 mL vial and sealed rapidly. The vial was immediately heated to 70 degrees C in an aluminium block heater, the needle of the SPME device was inserted through the septum of the vial, and the extraction fiber was exposed to the headspace for 15 min. Afterwards, the compounds extracted by the fiber were desorbed simultaneously by exposing the fiber in the gas chromatograph injection port. No interferences were found, and the time for analysis was about 30 min for one sample. This method was applied to a suicide case in which the victim ingested naphthalene, fluorene, and anthracene.