Gas Chromatography-flame Ionization Detector Analysis Research Articles

Phytochemical screening and GC-FID identification of bioactive compounds in n-hexane, ethylacetate and methanol fractions of methanolic leaves extract of Azanza garckeana

Azanza garckeana is a tropical African plant commonly used for food and medicine. This study was aimed at evaluating the antioxidant, phytochemicals and the bioactive compounds present in n-hexane, ethylacetate and methanol fractions of the methanolic extract of Azanza garckeana leaves. Phytochemical screening and antioxidant assayed were carried out using standard methods, while bioactive compounds were analyzed using gas chromatography-flame ionization detector (GC-FID). The phytochemical compositions revealed considerable level of tannins and saponins with moderate concentration of flavonoids and steroids in the methanol fraction; whereas n-hexane fraction also showed considerable amount of tannins followed by saponins and a low concentration of steroids. However, ethylacetate fraction had the highest yield of tannins, steroids, and terpenoids which were significantly (p < 0.05) higher than methanolic fraction and n-hexane fraction respectively. The antioxidant activity of the methanolic crude extract of A. garckeana leaves showed that the % DPPH radical scavenging activity of the crude extract increased with decreased in concentration when compared with the standard antioxidant (ascorbic acid). The result of GC-FID analysis revealed the presence of nineteen constituents in n-hexane fraction, while ethylacetate and methanol fractions each have twenty constituents. This result showed that Azanza garckeana leaves contain health-promoting bioactive compounds with potent antioxidants.

The Effect of Fermentation Time, pH and Saccharomyces Cerevisiae Concentration for Bioethanol Production from Ulva Reticulata Macroalgae

Research has been carried out on the effect of pH, fermentation time and yeast concentration on bioethanol production through hydrolysis using a CEM (Ceramic Elekctromagnetic Microwave) synthesizer and bioethanol production from Ulva reticulata seaweed. Ulva reticulata seaweed contains carbohydrates in the form of heteropolysaccharides such as glucose, arabinose, ramnose and xylose which are very abundant and suitable for conversion into bioethanol because the people of Timor Island do not use them as food. The carbohydrate content of Ulva reticulata seaweed can be converted into hexose and pentose sugars (glucose, arabinose, ramnose and xylose) through hydrolysis using 3 types of acid catalysts, namely hydrochloric acid (HCl), sulfuric acid (H2SO4) and nitric acid (HNO3). Fermentation was carried out with S. cerevisiae concentration variation of 6; 8; 10; 12 % (v/v) and fermentation time variation of 3; 5; 7; 9 days and a pH variation of 4; 4.5; 5; 5.5 at a temperature of 30 °C. Reducing sugar characterization used the Dinitrosalicylic acid (DNS) reagent, sample surface texture analysis was carried out using Scanning Electron Microscopy (SEM) and ethanol characterization used Gas Chromatography-Flame Ionization Detector (GC-FID). The results of surface texture analysis before and after hydrolysis experienced significant changes. Optimal conditions for hydrolysis of Ulva reticulata seaweed using sulfuric acid (H2SO4) combined with a CEM synthesizer at an acid concentration of 3 % (v/v) with irradiation power of 200 watts for 50 min at a temperature of 150 °C, produced reducing sugar of 97.06 g/L. The results of GC-FID analysis indicated that bioethanol concentration obtained at optimal conditions of pH 4.5 was 42.32 %, S. cerevisiae concentration was 12 % with a bioethanol content of 42.53 % at a fermentation time of 5 days. This research is expected to provide information for researchers and industry to overcome world energy problems and environmental pollution through Ulva reticulata waste. HIGHLIGHTS The results of surface texture analysis before and after hydrolysis experienced significant changes. Optimum conditions for hydrolysis of Ulva reticulata seaweed using sulfuric acid (H2SO4) combined with a CEM synthesizer at an acid concentration of 3 % (v/v) with irradiation power of 200 watts for 50 min at a temperature of 150 °C, producing reducing sugar of 97.06 g /L. GRAPHICAL ABSTRACT

Solvent Extraction of PDMS Tubing as a New Method for the Capture of Volatile Organic Compounds from Headspace.

Polydimethylsiloxane (PDMS) tubing is increasingly being used to collect volatile organic compounds (VOCs) from static biological headspace. However, analysis of VOCs collected using PDMS tubing often deploys thermal desorption, where samples are considered as 'one-offs' and cannot be used in multiple experiments. In this study, we developed a static headspace VOC collection method using PDMS tubing which is solvent-based, meaning that VOC extracts can be used multiple times and can be linked to biological activity. Using a synthetic blend containing a range of known semiochemicals (allyl isothiocyanate, (Z)-3-hexen-1-ol, 1-octen-3-one, nonanal, (E)-anethol, (S)-bornyl acetate, (E)-caryophyllene and pentadecane) with differing chemical and physicochemical properties, VOCs were collected in static headspace by exposure to PDMS tubing with differing doses, sampling times and lengths. In a second experiment, VOCs from oranges were collected using PDMS sampling of static headspace versus dynamic headspace collection. VOCs were eluted with diethyl ether and analysed using gas chromatography - flame ionization detector (GC-FID) and coupled GC - mass spectrometry. GC-FID analysis of collected samples showed that longer PDMS tubes captured significantly greater quantities of compounds than shorter tubes, and that sampling duration significantly altered the recovery of all tested compounds. Moreover, greater quantities of compounds were recovered from closed compared to open systems. Finally, analysis of orange headspace VOCs showed no qualitative differences in VOCs recovered compared to dynamic headspace collections, although quantities sampled using PDMS tubing were lower. In summary, extraction of PDMS tubing with diethyl ether solvent captures VOCs from the headspace of synthetic blends and biological samples, and the resulting extracts can be used for multiple experiments linking VOC content to biological activity.

Identification of volatile biomarkers for high-throughput sensing of soft rot and Pythium leak diseases in stored potatoes

Soft rot and Pythium leak are postharvest storage diseases of potato tubers that can cause substantial crop losses in the US. This study focused on detecting volatile organic compounds (VOCs) associated with rot inoculated tubers during storage (up to 21 days) using headspace solid-phase microextraction (SPME) coupled to gas chromatography (GC) with mass spectrometry (MS) and flame ionization detector (FID) analysis. Russet Burbank and Ranger Russet tubers were inoculated with the rot pathogens. Static sampling with 50 min trapping time followed by GC–MS and GC–FID analysis identified 23 and 30 common VOCs from the pathogen inoculated tubers. Overall, n,n–dimethylmethylamine, acetone, 1–undecene, and styrene, occurred frequently and repeatability in inoculated samples based on GC–MS analysis, with the latter two found using GC–FID analysis as well. Identification of such biomarkers can be useful in developing high-throughput VOC sensing systems for early disease detection in potato storage facilities.

In vitro antiplasmodial activity, cytotoxicity, and gas chromatography – flame ionization detector metabolites fingerprint of extracts and fractions from Tetrorchidium didymostemon

BackgroundTetrorchidium didymostemon is used as an antimalarial remedy in southern Nigeria. Objective(s)This study was aimed at providing scientific validation for the use of T. didymostemon in the treatment of malaria in Nigeria. Materials and methodsPlasmodium falciparum 3D7 (Pf3D7) strain was cultured and maintained in fresh O+ human erythrocytes. Standard methods were used to evaluate in vitro antiplasmodial activity, cytotoxic effect on Vero cell line, phytochemical screening, and antioxidant capacity. Gas Chromatography – Flame Ionization Detector (GC-FID) metabolite fingerprinting of the most potent fraction was carried out. ResultsThe methanol leaf extract had higher antiplasmodial activity (IC50Pf3D7 = 25 ± 0.21 μg/mL) in comparison with the stem bark extract (SBE) (IC50Pf3D7 = 50 ± 0.94 μg/mL). The n-hexane fraction of the leaf extract had the best antiplasmodial activity (IC50Pf3D7 = 3.92 ± 0.46 μg/mL) and selectivity index. This was followed by the dichloromethane (IC50Pf3D7 = 12.5 ± 1.32 μg/mL), ethyl acetate (IC50Pf3D7 = 35.0 ± 4.80 μg/mL), and hydromethanol fraction which was inactive (IC50Pf3D7 > 100 μg/mL). All extracts and fractions were not toxic on Vero cell line (CC50 > 1000 μg/mL). The n-hexane and dichloromethane fractions had the highest amount of phytochemicals. GC-FID analysis revealed high amounts of kaempferol, α-pinene, camphor, humulene, azulene, and β-caryophyllene in the n-hexane fraction. ConclusionThe results of our study validate the traditional use of T. didymostemon in the treatment of malaria in southern Nigeria. They also suggest that the phytoconstituent(s) responsible for the antiplasmodial activity of this plant may be more extractable in non-polar solvents.

Gas chromatography-flame ionization detector analysis of AMB-Fubinaca from criminal evidences in Vietnam

Gas chromatography-flame ionization detector analysis of AMB-Fubinaca from criminal evidences in Vietnam

Development of a needle trap device packed with titanium-based metal-organic framework sorbent for extraction of phenolic derivatives in air.

We developed a novel method of needle trap device packed with titanium-based metal-organic framework for the extraction of phenolic derivatives in air followed by gas chromatography-flame ionization detector analysis. The synthetized adsorbent was packed inside a 22-gauge spinal needle. This method was first tested at laboratory scale, and then was used for field sampling of phenolic derivatives in air. A glass chamber placed on a heater at 60°C was used to provide different concentrations of phenolic derivatives. The desorption conditions and breakthrough volume were optimized using response surface methodology. The limit of detection and limit of quantitation of the proposed method were estimated to be in the range of 0.001-0.12 and 0.003-0.62ng/mL, respectively, indicating a high sensitivity for the suggested sampler. Storing the packed needle trap device in a refrigerator at 4˚C for 60 days did not dramatically affect the storage stability. Our findings indicated that there was a high correlation coefficient (R2 =0.99) between the measurement results of this method and the NIOSH recommended method (XAD-7 sorbent tube). Therefore, it can be concluded that the needle trap device packed with titanium-based metal-organic framework can be used as a efficient method for extraction of phenolic derivatives in air.

GC-MS and GC-FID Analysis of Products from Glow Discharge in N2 + CH4 Mixture

This work extends our previous investigation of nitrogen-methane atmospheric glow discharge for the simulation of chemical processes in prebiotic atmospheres. Also reactions on surfaces of solid state bodies can be important. So in presented experiments the electrodes with different shapes and different surface areas were used. Exhaust products of discharge in this gas mixture were analyzed by Gas Chromatography - Mass Spectrometry (GC-MS) and Gas Chromatography - Flame Ionization Detector (GC-FID). The major products identified in chromatograms were hydrogen cyanide and acetylene.

Chemical composition and insecticidal activity of essential oil from coriander fruit against Tribolium castaenum, Sitophilus oryzae, and Lasioderma serricorne

ABSTRACTGas chromatography and gas chromatography–flame ionization detector analysis of essential oil of Coriandrum sativum fruit showed a high percentage of linalool (79.22%) γ-terpinene (6.26%), camphor (2.63%), α-pinene (2.32%), geranyl acetate (1.75%), and p-cymene (1.70%). Significant differences in insect mortality were observed within insect species, oil concentrations, and exposure time. Fumigant treatments have shown that three insect mortality rate increased with the increase in essential oils concentration. Complete insect mortality was detected at the highest concentration within 24 h of exposure for the single compound against Tribolium castaneum and Lasioderma serricorne. Probit analysis showed that LC50 values of coriander essential oil against L. serricorne than Sitophilus oryzae and T. castaneum were 5.25 µL/L air, and 145.49 µL/L air and 276.29 µL/L air, respectively. Among the test compound, linalool demonstrated strong fumigant toxicity against L. serricorne. These result could be important in order to the efficacy of essential oil of coriander and could be potential for use in the insecticidal activities.

Volatiles and surface wax long-chain alkanes and free fatty acids from Polygonum orientale L. (Polygonaceae) flowers

The n-hexane extracts of 25 g Polygonum orientale L. (Polygonaceae) flowers were analysed by thin-layer chromatography, gas chromatography–flame ionization detector (GC-FID) and gas chromatography–mass spectrometry (GC-MS) and revealed 20 long-chain alkanes from n-C15 to n-C36 and 13 free fatty acids from C12:0 to C21:0, accounting for 5784.52 ± 15.03 and 474.29 ± 3.63 μg, respectively. Octadecane and palmitoleic acid were the predominant alkane and free fatty acid in flower surface waxes, representing 691.14 ± 8.46 and 102.22 ± 1.50 μg, respectively. Floral volatiles were collected by a push–pull technique. Twenty-six compounds were identified by GC-MS and GC-FID analyses. Methyl jasmonate was predominant, followed by 1-octadecanol, representing 753.69 ± 31.76 and 294.09 ± 2.92 μg, respectively.

High-yield methods for purification of α-linolenic acid from Perilla frutescens var. japonica oil

This study was conducted to investigate the purification methods for high-yield of α-linolenic acid (ALA) from Perilla frutescens var. japonica oil (PO). PO was treated with 2 g of urea, cooled for 24 h, and 81.75 % of ALA was obtained after gas chromatography–flame ionization detector analysis. Urea complexation at low temperature (refrigeration) is a prospective method for the extraction of unsaturated fatty acids in high yields. Our results suggest that urea treatment with cooling at 10 °C could be used for purification of ALA from PO. It will be enhanced for the development of nutritional, medical, and cosmetic value.

Mechanism for the oxidation of phenol by sulfatoferrate(VI): Comparison with various oxidants

The oxidative action of a solid and stable potassium sulfatoferrate(VI) material on phenol was studied in aqueous solution under different stoichiometries. The performance towards phenol and the total organic carbon is compared to that of potassium permanganate and calcium hypochlorite. The total mineralization of phenol is not completely achieved by the studied chemical oxidants, and some oxidation products have been identified by gas chromatography-mass spectrometry and gas chromatography-flame ionization detector analysis. A radical reaction pathway, involving the formation of oxidation intermediates or by-products such as benzoquinone, phenoxyphenol and ring opening products, is proposed for the decomposition of phenol by ferrate(VI). Phenoxyphenol is also involved in the oxidation mechanism for permanganate whereas chlorinated phenols are produced by hypochlorite. The role of the chloride anion impurity of the potassium sulfatoferrate(VI) material has been highlighted in this study; no negative impact on the removal of phenol and its mineralization is observed compared to the use of a pure commercial ferrate(VI). The efficiency of sulfatoferrate(VI) for the oxidative removal of phenol from industrial wastewater is also confirmed.

Chitosan–Zinc Oxide Nanoparticles Combined with Dispersive Liquid–Liquid Microextraction for the Determination of BTEX in Water Samples

In this study, chitosan–zinc oxide nanoparticles were used as an adsorbent matrix for solid-phase extraction and combined with dispersive liquid–liquid microextraction (SPE–DLLME) for determination of benzene, toluene, ethylbenzene, and xylene isomers (BTEX) in water samples. The eluent of SPE was used as the dispersive solvent of the DLLME for further purification and enrichment of the BTEX prior to gas chromatography-flame ionization detector analysis. The effect of variables, including amount of adsorbent, sample and eluent flow rate, type and volume of extraction and dispersive solvent, salt concentration, and extraction time, was investigated and they were optimized. Under the optimum conditions, good linearity for all BTEX with determination coefficients in the range of 0.9993 &lt; r2 &lt; 0.9997, suitable precision (1.4 % &lt; RSD &lt;1.9 %; where RSD refers to relative standard deviation), and low detection limits (0.5–1.1 µg L–1) were achieved. The current chitosan–zinc oxide nanoparticles SPE–DLLME procedure combines the advantages of SPE and DLLME, and was applied for determination of BTEX in water samples and acceptable recoveries were obtained.

Microalgal fatty acid methyl ester a new source of bioactive compounds with antimicrobial activity

ObjectiveTo evaluate fatty acid composition and the antimicrobial activity of the major fraction of fatty acid methyl ester (FAME) extracts from three microalgae collected from freshwater lakes in Theni District, Tamil Nadu, India. MethodsAntimicrobial study was carried out by well diffusion method against bacterial as well as fungal pathogens such as Escherichia coli, Staphylococcus aureus, Enterobacter sp., Klebsiella sp., Salmonella typhi, Fusarium sp., Cryptococcus sp., Candida sp., and Aspergillus niger and Aspergillus flavus. The FAME profiles were determined through gas chromatography with a flame ionization detector. ResultsThe FAME was found to be radial effective in inhibiting the radial growth of both bacterial and fungal pathogens. The FAME extracts exhibited the antibacterial activity against three clinical pathogens, namely, Escherichia coli, Salmonella typhi and Enterobacter sp. with the maximum zone of inhibition of 12.0 mm, 12.0 mm and 11.0 mm, respectively. The FAME showed moderate antifungal activity against Cryptococcus sp. (11.8 mm), Aspergillus niger (10.5 mm), Candida sp. (11.8 mm) and Fusarium sp. (10.4 mm). Gas chromatography-flame ionization detector analysis revealed about 30 different FAMEs. ConclusionsWe assume that the observed antimicrobial potency may be due to the abundance of erucic acid methyl ester (C22:0), arachidic acid methyl ester (C20:0), palmitic acid methyl ester (C16:0), cis-11-eicosenoicmethyl ester (C20:1), cis-11, 14-eicosadienoic acid methyl ester (C20:2) and linolenic acid methyl ester (C18:3) in FAMEs which appears to be promising to treat microbial diseases.

Electromembrane Surrounded Solid Phase Microextraction Followed by Injection Port Derivatization and Gas Chromatography–Flame Ionization Detector Analysis for Determination of Acidic Herbicides in Plant Tissue

Electromembrane surrounded solid phase microextraction (EM-SPME) of acidic herbicides was studied for the first time. In order to investigate the capability of this new microextraction technique to analyze acidic targets, chlorophenoxy acid (CPA) herbicides were quantified in plant tissue. 1-Octanol, was sustained in the pores of the wall of a hollow fiber and served as supported liquid membrane (SLM). Other EM-SPME related parameters, including extraction time, applied voltage, and pHs of the sample solution and the acceptor phase, were optimized using experimental design. A 20 min time frame was needed to reach the highest extraction efficiency of the analytes from a 24 mL alkaline sample solution across the organic liquid membrane and into the aqueous acceptor phase through a 50 V electrical field, and to their final adsorption on a carbonaceous anode. In addition to high sample cleanup, which made the proposed method appropriate for analysis of acidic compounds in a complicated media (plant tissue), 4.8% of 2-methyl-4-chlorophenoxyacetic acid (MCPA) and 0.6% of 2,4-dichlorophenoxyacetic acid (2,4-D) were adsorbed on the anode, resulting in suitable detection limits (less than 5 ng mL-1), and admissible repeatability and reproducibility (intra- and interassay precision were in the ranges of 5.2-8.5% and 8.8-12.0%, respectively). Linearity of the method was scrutinized within the ranges of 1.0-500.0 and 10.0-500.0 ng mL-1 for MCPA and 2,4-D, respectively, and coefficients of determination greater than 0.9958 were obtained. Optimal conditions of EM-SPME of the herbicides were employed for analysis of CPAs in whole wheat tissue.

English

In this investigation, antihyperglycemic and antioxidant potential of oil of seeds of&nbsp;Arachis hypogaea&nbsp;(AHO) in streptozotocin-nicotinamide (STZ) induced type 2 diabetic rats was observed along with gas chromatography flame ionization detector (GC-FID) analysis.&nbsp;AHO was orally administered to diabetic rats to study its effect in both acute and chronic antihyperglycemic study. The body weight, oral glucose tolerance test and biochemical parameters: glucose level, insulin level, liver glycogen content, glycosylated hemoglobin and antioxidant parameters were estimated for all treated groups and compared against diabetic control group.&nbsp;GC-FID analysis showed the presence of major constituents as oleic acid (48.4500%), linoleic acid (32.6355%), palmitic acid (12.6988%) and arachidic acid (4.0814%). AHO (500 and 1000 mg/kg) and glibenclamide (0.6 mg/kg) in respective groups of diabetic animals administered for 28 days reduced the blood glucose level in streptozotocin-nicotinamide induced diabetic rats. There was significant increase in body weight, liver glycogen content, plasma insulin level and decrease in the blood glucose and glycosylated hemoglobin in test groups as compared to control group.&nbsp;In vivo&nbsp;antioxidant studies on STZ-nicotinamide induced diabetic rats revealed decreased malondialdehyde (MDA) and increased reduced glutathione (GSH). Thus the investigation results that oil of seeds of&nbsp;A hypogaeahave significant antihyperglycemic and antioxidant activity. &nbsp; Key words:&nbsp;Seeds, Streptozotocin, Essential oil, MDA.

Development of an automated data processing method for sample to sample comparison of seized methamphetamines

The information about the sources of supply, trafficking routes, distribution patterns and conspiracy links can be obtained from methamphetamine profiling. The precursor and synthetic method for the clandestine manufacture can be estimated from the analysis of minor impurities contained in methamphetamine. Also, the similarity between samples can be evaluated using the peaks that appear in chromatograms. In South Korea, methamphetamine was the most popular drug but the total seized amount of methamphetamine whole through the country was very small. Therefore, it would be more important to find the links between samples than the other uses of methamphetamine profiling. Many Asian countries including Japan and South Korea have been using the method developed by National Research Institute of Police Science of Japan. The method used gas chromatography-flame ionization detector (GC-FID), DB-5 column and four internal standards. It was developed to increase the amount of impurities and minimize the amount of methamphetamine. After GC-FID analysis, the raw data have to be processed. The data processing steps are very complex and require a lot of time and effort. In this study, Microsoft Visual Basic Application (VBA) modules were developed to handle these data processing steps. This module collected the results from the data into an Excel file and then corrected the retention time shift and response deviation generated from the sample preparation and instruments analysis. The developed modules were tested for their performance using 10 samples from 5 different cases. The processed results were analyzed with Pearson correlation coefficient for similarity assessment and the correlation coefficient of the two samples from the same case was more than 0.99. When the modules were applied to 131 seized methamphetamine samples, four samples from two different cases were found to have the common origin and the chromatograms of the four samples were appeared visually identical. The developed VBA modules could process raw data of GC-FID very quickly and easily. Also, they could assess the similarity between samples by peak pattern recognition using whole peaks without spectral identification of each peak that appeared in the chromatogram. The results collectively suggest that the modules would be useful tools to augment similarity assessment between seized methamphetamine samples.

Fatty acids composition in seeds of the South American glasswort Sarcocornia ambigua

Sarcocornia ambigua (Michx.) M.A. Alonso & M.B. Crespo is the most widely distributed species of the perennial genus of glasswort in South America, and it shows great biotechnological potential as a salt-water irrigated crop. Qualitative and quantitative compositions of fatty acids were determined in the seeds of S. ambigua that were cultivated in southern Brazil. Hexane extraction of the seed oil from S. ambigua yielded 13% of total lipids. The GC-FID (Gas Chromatography Flame Ionization Detector) analysis of the hexane extracts showed five prominent peaks for the seed oil: 42.9 wt.% linoleic-ω6 acid (18:2), 20.4 wt.% palmitic acid (16:0), 18.5 wt.% oleic acid (18:1), 4.5 wt.% stearic acid (18:0) and 4.0 wt.% linolenic-ω3 acid (18:3). The sum of the saturated palmitic and stearic acids (24.8%) in S. ambigua seed oil exceeded values cited for commercial oils use, as well as the seed oil from the cultivated annual glasswort Salicornia bigelovii. No undesirable fatty acid components were found in S. ambigua seed oil, and it could be recommended for animal consumption or biofuel production.

Synthesis and Application of High Selective Monolithic Fibers Based on Molecularly Imprinted Polymer for SPME of Trace Methamphetamine

A monolithic solid-phase microextraction (SPME) fiber was fabricated based on a molecularly imprinted polymer which could be coupled with gas chromatography for extraction, pre-concentration and determination of methamphetamine (MAMP). Methacrylic acid, ethylene glycol dimethacrylate and MAMP play the roles of functional monomer, cross-linker and template, respectively. The effective factors influencing the polymerization and extraction procedures were investigated and will be detailed here. The fabricated fiber was firm, inexpensive, stable, selective and durable which gives it vital importance in SPME. Selectivity of the fabricated fiber in relation to the template in solution containing MAMP, related and unrelated compounds was also investigated. Under the optimum conditions, the calibration plot was linear in the range of 50–3,500 ng mL−1 (r2 = 0.997). The high extraction efficiency was obtained for MAMP giving a detection limit of 14 ng mL−1. The fabricated fiber was successfully applied to SPME of MAMP from human saliva samples followed by gas chromatography-flame ionization detector analysis.

Determination of the UK37 index in geological samples

The U K 37 index is a tool for sea surface paleotemperature (SST) reconstruction and is defined by the relative abundance of three long-chain alkenones (C 37 ) commonly found in Quaternary marine sediments. A simple, fast, and reliable antical technique is required for the analysis of these compounds in deep-sea sediment cores in order to pride time series of SST and hence contribute to the understanding of past climates. The method described here employs a robotic workstation for sample preparation and gas chromatography (GC) coupled to mass spectrometry with ammonia chemical ionization (CI-MS) to quantify the targeted analytes. This semiautomated procedure provides enhanced sensitivity, selectivity, and speed of analysis when compared to conventional, manual sample preparation and GC flame ionization detector analysis