The Experts below are selected from a list of 5745 Experts worldwide ranked by ideXlab platform
R M Marce - One of the best experts on this subject based on the ideXlab platform.
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determination of pesticides in environmental waters by solid phase extraction and gas chromatography with Electron Capture and mass spectrometry detection
Journal of Chromatography A, 1997Co-Authors: Carme Aguilar, F Borrull, R M MarceAbstract:A group of pesticides with different chemical structures was determined by solid-phase extraction on LiChrolut EN cartridges and gas chromatography with Electron-Capture detection or mass spectrometry. The parameters affecting the solid-phase extraction process were optimized and the responses obtained by both GC detection systems were compared. The use of an Electron-Capture Detector enabled the organochlorine pesticides studied to be determined at ng 1−1 levels whereas mass spectrometry under selective ion monitoring acquisition enabled levels of low μg 1−1 to be reached. The R.S.D. (n=6) of the method in tap water was lower than 8.1% for Electron-Capture and mass spectrometric detection. The methods developed were used to determine the pesticides studied in tap and river water and some pesticides could be found in Ebro river and Ebro delta water.
Dariel C Rakestraw - One of the best experts on this subject based on the ideXlab platform.
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determination of amantadine in human plasma by capillary gas chromatography using Electron Capture detection following derivatization with pentafluorobenzoyl chloride
Journal of Pharmaceutical and Biomedical Analysis, 1993Co-Authors: Dariel C RakestrawAbstract:Abstract A specific, sensitive, and accurate capillary gas chromatographic method for the quantitation of amantadine in human plasma is described. Amantadine and the internal standard, rimantadine were extracted from plasma under alkaline conditions into toluene. Both compounds were derivatized with pentafluorobenzoyl chloride. The derivatives were separated on a HP-1 capillary column at 180°C and detected using a 63 Ni Electron-Capture Detector. The minimum quantifiable limit of the assay is 2.3 ng ml −1 of amantadine base using 1 ml of plasma. The method was used to evaluate the bioequivalence of two different formulations of amantadine hydrochloride.
Weixiong Huang - One of the best experts on this subject based on the ideXlab platform.
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rapid analysis of cyclamate in foods and beverages by gas chromatography Electron Capture Detector gc ecd
Food Chemistry, 2012Co-Authors: Shengbing Yu, Fen Lv, Shaoxiao Li, Weixiong HuangAbstract:Abstract A rapid method for determination of sodium cyclamate in foods and beverages was developed. Sodium cyclamate was converted to N,N-dichloridecyclohexylamine by reaction with sodium hypochlorite under acid condition. N,N-dichloridecyclohexylamine was subsequently extracted by n-hexane and determined by gas chromatography. Conditions such as derivatization time, the concentration of sodium hypochlorite and sulphuric acid were optimised. Amino acids, aliphatic amines, and food additives such as preservatives, dyes and sweeteners showed no interference for quantification of cyclamate. The correlation coefficient of calibration curve was 0.9993 in the range of 5.0–250 mg/L. The limits of detection (LOD) and limits of quantification (LOQ) were calculated as three or ten times the signal-to-noise ratio (S/N), respectively. The LOD and LOQ for yellow wine and fruit juice were 0.05 and 0.2 mg/L, respectively. The LOD and LOQ for cake and preserved fruit were 0.25 and 0.8 mg/kg, respectively. The intra-day and inter-day RSD were 0.28% and 1.1% (n = 5), respectively. The method was successfully applied for determination of cyclamate in yellow wine, cake, fruit juice and preserved fruit. This method was simple, fast, and sensitive. It was suitable for the determination of cyclamate in foods and beverages for safety and quality control inspections.
Hassan Y Aboulenein - One of the best experts on this subject based on the ideXlab platform.
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simultaneous determination of cypermethrin and fenvalerate residues in tomato by gas chromatography and their applications to kinetic studies after field treatment
Biomedical Chromatography, 2012Co-Authors: Mahgoub Ibrahim Shinger, Hassan Elobid Ahmed, Abdalla A Elbashir, Hassan Y AbouleneinAbstract:In this study simultaneous determination of cypermethrin and fenvalerate residues in tomato fruit (Lycopesicon esculentum) grown in Khartoum, Sudan, was carried out using gas chromatography with Electron Capture Detector (GC-ECD). The method was linear in the ranges of 0.075-0.009 and 0.75-0.037 mg/mL for cypermethrin and fenvalerate, respectively. The limits of detection and quantification were found to be 0.003 and 0.01 mg/mL and 0.014, 0. 047 mg/mL for cypermethrin and fenvalerate, respectively. The recoveries of cypermethrin and fenvalerate spiked in tomato were 97 ± 7.5 and 99.5 ± 1.8%, respectively. The kinetic study of the degradation of both pesticides was performed and the ultimate evaluation of the kinetic data revealed a first-order kinetics with respect to the tomato fruit; an explanation was put forward to account for the results.
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a gas chromatographic method with Electron Capture Detector gc ecd for simultaneous determination of fenpropathrin λ cyhalothrin and deltamethrin residues in tomato and its applications to kinetic studies after field treatment
Food Analytical Methods, 2012Co-Authors: Abuzar E A E Albadri, Hassan Elobid Ahmed, Ibrahim A M Mihaina, Abdalla A Elbashir, Hassan Y AbouleneinAbstract:In this study, simultaneous determination of fenpropathrin, λ-cyhalothrin, and deltamethrin in tomato fruit (Lycopesicon esculentum) grown in Khartoum, Sudan, was carried out using gas chromatography with Electron Capture Detector (GC-ECD).The method was linear in the range of 0.001–0.01, 0.001–0.01 and 0.001–0.02 mg/ml for fenpropathrin, λ-cyhalothrin, and deltamethrin, respectively. The limit of detection (LOD) and limit of quantification (LOQ) were found to be 0.0012 and 0.0041, 0.0013 and 0.0041 and 0.0026 and 0.0087 mg/ml for fenpropathrin, λ-cyhalothrin, and deltamethrin, respectively. The recoveries of fenpropathrin, λ-cyhalothrin, and deltamethrin at three concentration levels spiked to tomato were found to be in range 85.77 ± 1.52–95.61 ± 3.65%, 91.77 ± 4.34–98.59 ± 2.46% and 92.61 ± 2.46–98.04 ± 2.93%, respectively. The kinetic study of the degradation of all pesticides was performed and the ultimate evaluation of the kinetic data revealed a pseudo first order kinetics pattern for fenpropathrin, λ-cyhalothrin, and deltamethrin.
Yoshihiro Fujise - One of the best experts on this subject based on the ideXlab platform.
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validation of high throughput measurement system with microwave assisted extraction fully automated sample preparation device and gas chromatography Electron Capture Detector for determination of polychlorinated biphenyls in whale blubber
Chemosphere, 2009Co-Authors: Hiroyuki Fujita, Katsuhisa Honda, Noriaki Hamada, Genta Yasunaga, Yoshihiro FujiseAbstract:Abstract Validation of a high-throughput measurement system with microwave-assisted extraction (MAE), fully automated sample preparation device (SPD), and gas chromatography-Electron Capture Detector (GC-ECD) for the determination of polychlorinated biphenyls (PCBs) in minke whale blubber was performed. PCB congeners accounting for >95% of the total PCBs burden in blubber were efficiently extracted with a small volume (20 mL) of n -hexane using MAE due to simultaneous saponification and extraction. Further, the crude extract obtained by MAE was rapidly purified and automatically substituted to a small volume (1 mL) of toluene using SPD without using concentrators. Furthermore, the concentration of PCBs in the purified and concentrated solution was accurately determined by GC-ECD. Moreover, the result of accuracy test using a certified material (SRM 1588b; Cod liver oil) showed good agreement with the NIST certified concentration values. In addition, the method quantification limit of total-PCB in whale blubbers was 41 ng g −1 . This new measurement system for PCBs takes only four hours. Consequently, it indicated this method is the most suitable for the monitoring and screening of PCBs in the conservation of the marine ecosystem and safe distribution of foods.