LC-MS/MS Determination of 21 Non-Steroidal Anti-Inflammatory Drugs Residues in Animal Milk and Muscles

The presented procedure combines experience from two LC-MS/MS methods previously developed by our team for NSAIDs determination in meat and milk. The novelty was a modification of sample preparation and combining LC-MS/MS method for milk and muscle. The clean-up procedure was investigated, leading to a change from SPE to dSPE with C18 bulk sorbent. Unlike most of the existing methods, chromatographic separation was achieved on a C8 chromatographic column. This method was developed and validated under European Commission Decision 2002/657/EC. Recovery for milk samples values between 86.3% to 108%, with the coefficient of variation, varied from 5.51% to 16.2%. The recovery for muscle was calculated to be between 85.0% and 109%, and the coefficient of variation was—4.73% to 16.6%. The validation results prove that the method is suitable for confirmatory purposes in milk and muscle. Of 452 samples tested in 2019 and 2020, two have been identified as non-compliant.

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Effect of Fat on Protein Estimation in Milk and Its Correlation with Lactose in Different Milk Types: A Small-Scale Study

Asian Journal of Dairy and Food Research ◽

10.18805/ajdfr.dr-1567 ◽

2020 ◽

Author(s):

Sweekruthi A. Shetty ◽

Melissa F. Young ◽

Sunita Taneja ◽

Kannan Rangiah

Keyword(s):

Sample Preparation ◽

Human Milk ◽

Internal Standard ◽

Cow Milk ◽

Selected Reaction Monitoring ◽

Small Scale ◽

Milk Samples ◽

Protein Estimation ◽

Animal Milk ◽

Fat Removal

Background: Estimation of macronutrients like protein and lactose is important to assess the quality of milk. To estimate these two macronutrients, ten raw milk samples obtained from each group of different animals (cow, goat, buffalo), ten pasteurized cow milk and ten human milk samples were analysed. Methods: Bicinchoninic acid (BCA) method was used to estimate protein from different milk samples. Four different sample preparation protocols were compared to check the effect of fat on BCA based protein estimation: dilution (D), fat removal-protein precipitation (FR and PP), fat removal-dilution (FR and D) and dilution-fat removal (D and FR). For lactose quantification, ultrahigh-performance liquid chromatography-mass spectrometry-selected reaction monitoring (UHPLC-MS/SRM) method was developed and validated using 13C6 lactose as internal standard (ISTD).Result: Among these four different protocols, D and FR method showed consistent data for total protein content in animal milk (cow-3.16%, goat-3.21%, buffalo-3.81%, pasteurized-2.98%) and FR and PP showed consistent data in human milk samples (1.2%). Though BCA method is simple to use, proper sample preparation protocol has to be applied prior to protein estimation to avoid the interference due to fat or lactose. In case of lactose, inter-day validation showed the accuracy ranging from 97.13 to 100.54%, coefficient of variation varying between 0.1 to 1.53%, correlation R2=0.999. Lactose is in the range of 4.1 to 4.8% in animal milk and 6.6% in human milk samples. The internal ratio of lactose/protein (1.28 to 1.55 in animal milk and 5.33 in human milk) will be useful to differentiate human milk from animal milk type and to assess the milk quality.

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Use of Stabilized Plasma Arc Excitation in Determining the Element Boron in Gasoline

Applied Spectroscopy ◽

10.1366/000370265789620032 ◽

1965 ◽

Vol 19 (2) ◽

pp. 57-58 ◽

Cited By ~ 8

Author(s):

M. S. Vigler ◽

J. K. Failoni

Keyword(s):

Standard Deviation ◽

Sample Preparation ◽

Ethyl Alcohol ◽

Coefficient Of Variation ◽

Internal Standard ◽

National Bureau ◽

Plasma Arc ◽

Buffer Solution ◽

Arc Excitation

This report describes the use of a stabilized plasma arc source in the quantitative spectrographs determination of boron in gasoline. The advantage is that the plasma arc requires no preliminary sample preparation other than addition of nickel hexoate internal standard in ethyl alcohol buffer solution. The National Bureau of Standards # 1063 menthyl borate may be used for preparing calibration curves. The method is applicable to the determination of boron in the range of 0.0001 to 0.0010 per cent. The standard deviation is 0.000055 per cent; the coefficient of variation is 8.1 per cent.

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Evaluation of sample preparation and chromatographic separation for the parallel determination of taurine and edaravone in rat tissues using HILIC-MS/MS

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-015-8635-0 ◽

2015 ◽

Vol 407 (14) ◽

pp. 4143-4153 ◽

Cited By ~ 2

Author(s):

Yin-jie Li ◽

Zheng Li ◽

Xiao-xiao Zheng ◽

Xiao-wen Wu ◽

Shi-rui Wang ◽

...

Keyword(s):

Sample Preparation ◽

Chromatographic Separation ◽

Rat Tissues

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Determination of albumin adducts of (+)-anti-benzo[a]pyrene-diol-epoxide using an high-performance liquid chromatographic column switching technique for sample preparation and gas chromatography–mass spectrometry for the final detection

Journal of Chromatography B Biomedical Sciences and Applications ◽

10.1016/s0378-4347(98)00208-4 ◽

1998 ◽

Vol 713 (2) ◽

pp. 331-337 ◽

Cited By ~ 11

Author(s):

Stefanie Frank ◽

Thomas Renner ◽

Thomas Ruppert ◽

Gerhard Scherer

Keyword(s):

Mass Spectrometry ◽

Gas Chromatography ◽

Sample Preparation ◽

High Performance ◽

High Performance Liquid Chromatographic ◽

Column Switching ◽

Chromatographic Column ◽

Gas Chromatography Mass Spectrometry ◽

Liquid Chromatographic

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Gas Chromatographic Determination of Alachlor in Microencapsulated Formulations: Mini-Collaborative Study

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/70.6.1056 ◽

1987 ◽

Vol 70 (6) ◽

pp. 1056-1058

Author(s):

David F Tomkins

Keyword(s):

Coefficient Of Variation ◽

Chromatographic Method ◽

Collaborative Study ◽

Internal Standard ◽

Chromatographic Determination ◽

Chromatographic Column ◽

Data Points ◽

Gas Chromatographic Method ◽

Isothermal Gas

Abstract An isothermal gas chromatographic method for measuring alachlor in Micro-Tech® (microencapsulated) formulations was tested by 5 collaborators. The samples were prepared in acetone, and alachlor was determined using a gas chromatographic column of 10% SP- 2250 on 100-120 mesh Supelcoport. Di-n-pentylphthalate was used as the internal standard. Collaborators made single determinations on 5 samples distributed as blind duplicates. The mini-collaborative study generated 47 data points. The coefficient of variation (CV„- pooled) was 1.35%, and CVx-pooled was 0.73%. The method was simple to use and did not reveal any interferences in samples tested. The method has been adopted official first action as an AOACCIPAC method.

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Development of Gas-Chromatographic Method for Simultaneous Determination of Cannabinoids and Terpenes in Hemp

Molecules ◽

10.3390/molecules25245872 ◽

2020 ◽

Vol 25 (24) ◽

pp. 5872

Author(s):

Jure Zekič ◽

Mitja Križman

Keyword(s):

Sample Preparation ◽

Simultaneous Determination ◽

Chromatographic Separation ◽

Chromatographic Method ◽

Linear Range ◽

Extraction Solvent ◽

Parallel Testing ◽

Medium Polarity ◽

Gas Chromatographic Method

An original gas chromatographic method has been developed for simultaneous determination of major terpenes and cannabinoids in plant samples and their extracts. The main issues to be addressed were the large differences in polarity and volatility between both groups of analytes, but also the need for an exhaustive decarboxylation of cannabinoid acidic forms. Sample preparation was minimised, also by avoiding any analyte derivatisation. Acetone was found to be the most appropriate extraction solvent. Successful chromatographic separation was achieved by using a medium polarity column. Limits of detection ranged from 120 to 260 ng/mL for terpenes and from 660 to 860 ng/mL for cannabinoids. Parallel testing proved the results for cannabinoids are comparable to those obtained from established HPLC methods. Despite very large differences in concentrations between both analyte groups, a linear range between 1 and 100 µg/mL for terpenes and between 10 and 1500 µg/mL for cannabinoids was determined.

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Methods For The Quantitative Determination Of Biocides In Tobacco And Tobacco Products. Part V: A Method For Rapid Determination Of The Urea Herbicide Metobromuron/Methoden Zur Quantitativen Bestimmung Von Bioziden In Tabak Und Tabakerzeugnissen. V. Mitteilung: Eine Schnellmethode Zur Bestimmung Des Harnstoff-Herbizides Metobromuron (Patoran)

Beiträge zur Tabakforschung International/Contributions to Tobacco Research ◽

10.2478/cttr-2013-0338 ◽

1974 ◽

Vol 7 (5) ◽

Author(s):

E. Nesemann ◽

F. Seehofer

Keyword(s):

Quantitative Determination ◽

Coefficient Of Variation ◽

Chromatographic Separation ◽

Rapid Determination ◽

Tobacco Products ◽

Aqueous Acetonitrile ◽

Gas Chromatographic Separation

AbstractDuring the attempt to transfer to tobacco a method commonly used to determine metobromuron in foodstuffs, it became apparent that only very small amounts of metobromuron and less than 0.1 ppm 4-bromoanilin were found. Nor did the modification of this method produce better results, because metobromuron, apparently linked to tobacco components, cannot be extracted with aqueous acetonitrile. The tobacco was then distilled under hydrolysing conditions and the 4-bromoanilin released was bound as hydrochloride. After gas-chromatographic separation 4-bromoanilin is determined specifically with the microcoulometer (bromine) and with the Coulson detector (nitrogen). The amount of metobromuron is calculated from the 4-bromoanilin. With this method no difference can be made between intact metobromuron and 4-bromoanilin already metabolised from metobromuron. Recovery is 90 % for 4-bromoanilin and 92 % for metobromuron, the coefficient of variation is 3.0 %. In cigarettes whose tobacco had grown in soil which had been treated with 4 kg of Patoran per hectare before transplanting, a mean of 5.8 ppm metobromuron was found by this procedure.

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Gas Chromatographic Determination of Calcium Propionate Added as Preservative to Bread

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/70.4.763 ◽

1987 ◽

Vol 70 (4) ◽

pp. 763-767

Author(s):

William M Lamkin ◽

Natalie C Unruh ◽

Yeshajahu Pomeranz

Keyword(s):

Gas Chromatography ◽

Phosphoric Acid ◽

Coefficient Of Variation ◽

Chromatographic Separation ◽

Chromatographic Determination ◽

Low Concentrations ◽

Average Coefficient ◽

Chromatographic Procedure ◽

Calcium Propionate

Abstract A simple and rapid gas chromatographic procedure was developed for determining low concentrations of propionate added as a preservative to bread. A bread sample to be analyzed was ground in a meat grinder with a 3 mm hole plate and finely divided by rubbing through a No. 8 sieve. The propionate was then extracted into 0.050M formic acid in a blender at low speed for 5 min, and an aliquot of a filtrate was analyzed directly by gas chromatography. Chromatographic separation was accomplished on a Carbopack C column coated with 0.3% (w/w) Carbowax 20M and 0.1% (w/w) phosphoric acid. Less than 0.2 ppm propionic acid could be detected in the aqueous extract. Over the range of 0.03-0.23% calcium propionate, average relative error was —1.20% with an average coefficient of variation of 2.02%.

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