Validation of an improved European standard method for the determination of PCBs in oil samples

Two European standard methods (EN 12766 and EN 61619) are currently used for the determination of PCBs in specific oil matrix. However, apolar matrix compounds (e.g. hydrocarbons) elute from the adsorbent together with the PCBs and are injected into the analytical system where their presence contaminates the inlet, detectors and columns; and decreases system performances. Insufficient cleanup causes delay of elution of PCBs from GC columns. By using new sulfoxide-bonded silica, PCBs are better separated from aliphatic hydrocarbons because the specificity of the stationary phase for these compounds is much higher that that used in both standard methods. A gas chromatograph AT6890 with two capillary columns of different polarities (HP-5MS and DB-1701) coupled to two μECDs is used. Oven temperature program is as followed: 90°C (1 min), 70°C/min to 180°C, 5°C/min to 230°C (0.1 min), 1.5°C/min to 280°C. Run time is 46 min. The procedure was validated through regular analysis of blanks, fortified samples (transformer oil, motor used and unused oil) and certified materials (BCR-449 and BCR-420, waste mineral oils, high and low PCB levels). Two internal standards were used (PCB 30 and PCB 209). An average recovery ± RSD of 82.8 ± 5.4 % was achieved for all six PCBs in different matrices. The LOQ per single PCB congener is 0.2 mg kg-1. The average recovery ± RSD for the BCR-420 is 92.0 ± 4.6 % and for the BCR-449 is 105 ± 2.5 % for all certified PCBs in waste oils.

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Determination of Aromatic Pollutants in Tap Water by a Gas Chromatograph Equipped with a Finger-sized Atomic Emission Detector Using Deuterated Internal Standards

BUNSEKI KAGAKU ◽

10.2116/bunsekikagaku.61.755 ◽

2012 ◽

Vol 61 (9) ◽

pp. 755-761 ◽

Cited By ~ 1

Author(s):

Ryutaro HIRANO ◽

Tatsuro NAKAGAMA ◽

Hizuru NAKAJIMA ◽

Hulie ZENG ◽

Katsumi UCHIYAMA

Keyword(s):

Tap Water ◽

Atomic Emission ◽

Gas Chromatograph ◽

Internal Standards ◽

Aromatic Pollutants ◽

Emission Detector ◽

Atomic Emission Detector

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Determination of Trifluralin in Formulations by Gas Chromatography

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/54.1.125 ◽

1971 ◽

Vol 54 (1) ◽

pp. 125-127

Author(s):

Larry G Hambleton

Keyword(s):

Gas Chromatography ◽

Chromatographic Method ◽

Internal Standard ◽

Flame Ionization Detector ◽

Gas Chromatograph ◽

Ionization Detector ◽

Average Recovery ◽

Flame Ionization ◽

Gas Chromatographic Method

Abstract A gas chromatographic method has been developed that is rapid and specific for trifluralin in formulations. The sample is extracted with acetone, an internal standard is added, and the solution is diluted to volume and injected into a gas chromatograph equipped with a flame ionization detector. Three typical trifluralin formulations were analyzed by both the gas chromatographic method and an ultraviolet method. The gas chromatographic method gave an average recovery of 101.2%.

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Improved Cleanup and Derivatization for Gas Chromatographic Determination of Monosodium Glutamate in Foods

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/66.6.1528 ◽

1983 ◽

Vol 66 (6) ◽

pp. 1528-1531 ◽

Cited By ~ 1

Author(s):

Hiroshi Nakanishi

Keyword(s):

Glutamic Acid ◽

Acid Derivative ◽

Monosodium Glutamate ◽

Chromatographic Determination ◽

Flame Ionization Detection ◽

Gas Chromatograph ◽

Flame Ionization ◽

Acetone Water ◽

Chromatographic Procedure

Abstract A gas chromatographic procedure is described for determining monosodium glutamate (MSG) in several types of food. A sample is extracted with acetone- water (1 + 1). Acetone is evaporated and an aliquot of the extract is buffered with 1M NH4OH-1M NH4CI pH 9 solution, and chromatographed directly on a column of QAE Sephadex A-25 that has been pretreated with the same buffer. MSG is eluted with 0.1N HC1, and a portion of the eluate is evaporated to dryness and reacted with dimethylformamide( DMF)-dimethylacetal to form the glutamic acid derivative, which is injected into a gas chromatograph and measured by flame ionization detection. Recoveries of MSG from sample fortified at 5-500 mg ranged from 92.8 to 100%.

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Migration of mineral oil in elastomers

Journal of Rubber Research ◽

10.1007/s42464-021-00087-7 ◽

2021 ◽

Author(s):

Tobias Förster ◽

Artur Blivernitz

Keyword(s):

Diffusion Coefficients ◽

Mineral Oil ◽

Activation Energies ◽

Concentration Profiles ◽

Small Reservoir ◽

Experimental Procedure ◽

Mineral Oils ◽

The Absolute ◽

Suitable Measure

AbstractThis work describes a newly introduced experimental procedure to quantify the diffusion progress of mineral oils locally resolved in NBR. Diffusion of reference oils IRM 901, IRM 902 and IRM 903 in NBR with various acrylonitrile contents was investigated. Classical sorption experiments were performed as a basic characterization and compared to the newly introduced method. Here, elastomer specimens are only being dipped with the bottom in a relatively small reservoir of mineral oil. This provides a determination of locally resolved concentration profiles of mineral oils, and the calculation of diffusion coefficients. These diffusion coefficients follow the same trends like those determined via sorption experiments. Despite differences in the absolute numbers, activation energies of diffusion can be applied as a suitable measure for the compatibility of elastomers and fluids.

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Colorimetric Determination of Aklomide (2-Chloro-4-Nitrobenzamide) in Poultry Feed

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/52.3.438 ◽

1969 ◽

Vol 52 (3) ◽

pp. 438-441

Author(s):

Glenn M George ◽

A C Daftsios ◽

Joseph L Morrison

Keyword(s):

Nitro Group ◽

Poultry Feed ◽

Colorimetric Determination ◽

Average Recovery ◽

Low Level ◽

Color Development ◽

Titanium Trichloride ◽

High Level

Abstract The coccidiostat aklomide is extracted from feed with methanol and assayed colorimetrically by reduction of the nitro group to anamine with titanium trichloride and subsequent color development with t he Bratton-Marshall reaction. Thirteen laboratories studied the method collaboratively on two levels of medicated feed. Overall average recovery was 106.5% of the oretical for the low level and 104.5% of the oretical for the high level. The method is recommended for adoption as official first action

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Gas Chromatographic Determination of Traces of Accelerants in Physical Evidence

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/55.4.840 ◽

1972 ◽

Vol 55 (4) ◽

pp. 840-845 ◽

Cited By ~ 1

Author(s):

Charles R Midkiff ◽

Willard D Washington

Keyword(s):

Liquid Chromatography ◽

Solvent Extraction ◽

Vapor Phase ◽

Selection Criteria ◽

Chromatographic Determination ◽

Operating Parameters ◽

Gas Liquid Chromatography ◽

Internal Standards ◽

Physical Evidence

Techniques developed for use with gas-liquid chromatography for the examination of evidence collected at the scene of suspected arson fires and firebombings are discussed. Both solvent extraction and vapor phase examinations are employed. Internal standards are used for the identification of specific components in actual samples to allow confirmation of hydrocarbon type, e.g., gasoline and kerosene. Operating parameters and solvent selection criteria are included. Results obtained from known materials and residual hydrocarbons in actual samples are compared.

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Determination of Chitosan Oligosaccharide Content by Acetylacetone Spectrophotometry Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.503-504.543 ◽

2012 ◽

Vol 503-504 ◽

pp. 543-547 ◽

Cited By ~ 2

Author(s):

Ze Ping Xu ◽

Chuan Lun Yang ◽

Xin Qing Zhang ◽

Xiu Zhi Wang ◽

Bao Sheng Huang

Keyword(s):

Hydrochloric Acid ◽

Linear Relationship ◽

Regression Equation ◽

Common Method ◽

Chitosan Oligosaccharide ◽

Average Recovery ◽

Good Linear ◽

Good Linear Relationship

Objective: To establish a common method to detect the content of chitosan oligosaccharide. Methods: Chitosan oligosaccharide was hydrolyzed completely by concentrated hydrochloric acid, and the solution was regulated into neutral with NaOH. Then, determined the absorbance in 525nm, and substituted into the regression equation to determine the results. Results: The results showed there was a good linear relationship when the concentration of chitosan oligosaccharide ranged from 0.02 mg/mL to 0.12 mg/mL, r2 = 0.999. The average recovery of chitosan oligosaccharide samples was 99.25%. Conclusion: The method is sensitive, accurate and simple. It is applied to determine of the content of chitosan oligosaccharide.

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Liquid Chromatographic Determination of Sulfamoyldapsone in Swine Tissues

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/70.6.1031 ◽

1987 ◽

Vol 70 (6) ◽

pp. 1031-1032

Author(s):

Yuuko S Endoh ◽

Ryozo Yamaoka ◽

Nobuo Sasaki

Keyword(s):

Detection Limit ◽

Quantitative Determination ◽

Chromatographic Determination ◽

Alumina Column ◽

Average Recovery ◽

Diaminodiphenyl Sulfone ◽

Alumina Column Chromatography ◽

Liquid Chromatographic Determination ◽

Liquid Chromatographic

Abstract A liquid chromatographic (LC) method is described for the quantitative determination of sulfamoyldapsone (2-sulfamoyl-4,4'-diaminodiphenyl sulfone) in swine muscle, liver, kidney, and fat. Sulfamoyldapsone was extracted from tissues with acetonitrile saturated with n-hexane. The extract was washed with n-hexane saturated with acetonitrile, concentrated, and cleaned up by alumina column chromatography. Sulfamoyldapsone was separated on an ODS column by using acetonitrile-methanol-water (6 + 18 + 76) and was detected at 292 nm. Overall average recovery of sulfamoyldapsone added to tissues at levels of 0.1 and 0.5 /μg/g was 93.3% ± 6.0. Detection limit was 0.02 μg/g in these tissues.

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