bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Fungicide Residues in White Grapes for Winemaking by Gas Chromatography with Mass Spectrometric Detection and Assessment of Matrix Effects
Authors: González Carlos Fernández , Otero Raquel Rial , Grande Beatriz Cancho , Gándara Jesús Simal 
Published: February 2020

Abstract
A new analytical method, based on organic solvent extraction with dichloromethane–acetone (75 + 25, v/v) followed by gas chromatography with mass spectrometric detection, is presented for the determination of residues of 10 fungicides in white grapes for vinification. Some of them (cyprodinil, fludioxonil, and pyrimethanil) have been used for only 2–3 years and, therefore, no methods are available in the scientific literature for such a screening. Quality parameters yielded good precision (relative standard deviation of &lt;10%) and detection limits (ranging between 1 and 18 μg/kg) that are lower than the maximum residue limits (MRLs) set by the 76/895/European Economic Community (EEC) and 90/642/EEC Directives. The applicability of the method was evaluated by analysis of 5 different white grapes produced in the Rías Baixas area in Galicia (northwestern Spain) for vinification. The method showed good performance in analyses of real samples to determine whether the concentrations of the fungicides used exceeded their MRLs. The method of standard additions was found to be necessary to avoid matrix effects in the quantification of fungicide residues. Results showed that concentrations of the fungicides identified in grapes were lower than the MRLs established by the European legislation.
Validity of the Percent Reduction in Standard Deviation Outlier Test for Screening Laboratory Means from a Collaborative Study
Authors: McClure Foster D , Lee Jung-Keun , Wilson Dennis B 
Published: February 2020

Abstract
AOAC INTERNATIONAL recommends an outlier test that is based on the “percent reduction in standard deviation” (PRSD) for screening the highest or lowest and 2-highest or 2-lowest laboratory means from a collaborative study. The original critical values that were developed to assess the significance of the test statistics associated with the PRSD test were obtained by simulation. In this paper, we answer several questions relative to the validity of the simulated critical values and develop formulas, based on the Student's t-distribution, to compare the simulated and formula-based critical values. Assumptions and derivations of formulas are provided along with selected tabular critical values that are used to test hypotheses at various levels of significance.
High-Performance Liquid Chromatography/Mass Spectrometry Analysis of Botanical Medicines and Dietary Supplements: A Review
Authors: Sherma Joseph 
Published: February 2020

Abstract
This article reviews research on the qualitative and quantitative analysis by high-performance column liquid chromatography/mass spectrometry (LC/MS) and LC/tandem mass spectrometry (LC/MS/MS) of botanical drugs, drug substances or preparations, and finished botanical products. In addition, LC/MS and LC/MS/MS techniques and commercial instruments are described and compared briefly, and prospects for future use of these methods for the analysis of botanicals are suggested. Some applications of direct MS without LC are also described.
Liquid Chromatographic Determination of Pyrantel Tartrate in Medicated Formulations
Authors: Konrardy Joyce A , Burner Mary A , Garner Tommy W , Litchman Mark A , Webster Gregory K 
Published: February 2020

Abstract
The validation of a novel liquid chromatographic (LC) method for the determination of pyrantel tartrate in feed is presented. The method provides a significant improvement over the efficiency and precision of AOAC Official Method 978.30. The method was shown to be accurate, precise, linear, and robust for medicated articles. Unlike the official method, the LC method was shown to be a superior stability-indicating method. After the method was validated by using laboratory blends, the effectiveness of the method was demonstrated with marketed product as well.
Photostimulated Luminescence Detection of Irradiated Herbs, Spices, and Seasonings: International Interlaboratory Trial
Authors: Sanderson David C W , Carmichael Lorna A , Fisk Saffron ,   Collaborators:, Brown P , Burton Y , Clemenson S D , Hart G , Nootenboom H , Pinnioja S , Schreiber G A , Wagner; U , Wiezorek C 
Published: February 2020

Abstract
An interlaboratory trial was conducted to validate photostimulated luminescence (PSL) methods for herbs, spices, and seasonings. Forty products (11 herbs, 17 spices, and 12 seasonings) were purchased from a local commercial source, and randomly selected samples were irradiated with 10 kGy. Four blended products were prepared at Scottish Universities Research and Reactor Centre, mixing varying proportions of irradiated material with the untreated product. Precharacterization against a predefined threshold identified low sensitivity products (black and white peppers) and products with high natural signals (thyme, sage, parsley, and mixed herbs), both of which might be susceptible to misclassification. Precharacterization also revealed whether calibration was likely to resolve overlap between classification categories. Eight sets of screening data and 5 sets of calibrated data were returned by participants. Of the 840 samples sent, 1593 screening measurements and 788 calibrated measurements were received from 662 samples. In screening mode, participants reached definitive conclusions in 87% of cases, 99% of which were correct. Of the remaining 13%, calibration to identify low-sensitivity resolved 60% of cases. Overall, 94% of samples were correctly identified by either screening alone, or screening plus calibration; 6% remained unclassified and therefore required further investigation by thermoluminescence. The results confirm the validity of the PSL method for herbs, spices, seasonings, and blends, and emphasize the need for calibration to identify low-sensitivity samples. This method has now been adopted by the European Committee for Standardization (CEN) and the Codex Alimentarius Commission.
Liquid Chromatographic Determination of 4, 4' -Dinitrocarbanilide, the Active Component of the Infertility Agent Nicarbazin, in Chicken, Duck, Goose, and Snake Eggs
Authors: Primus Thomas M , Kohler Dennis J , Goodall Margaret A , Yoder Christi , Mathies Thomas , Miller Lowell , Johnston John J , Vercauteren Kurt 
Published: February 2020

Abstract
4, 4'-Dinitrocarbanilide (DNC) was extracted from chicken, duck, goose, and snake eggs and isolated by reversed-phase liquid chromatography. DNC was detected by ultraviolet absorbance at 347 nm and quantitated by comparison with a calibration standard. Recoveries of DNC from fortified control chicken, duck, goose, and snake egg samples were determined for DNC levels of 0.16, 10, and 16 μg/g. The mean recoveries from chicken, duck, goose, and snake eggs were 92 ± 4, 88 ± 9, 87 ± 7, and 95 ± 6%, respectively. The method limits of detection for DNC in chicken, duck, goose, and snake eggs ranged from 0.015 to 0.035 μg/g. The reported method is much simpler than and equally efficient as previous methods developed for the determination of DNC residues in egg contents.
Syringe-Cartridge Solid-Phase Extraction Method for Patulin in Apple Juice
Authors: Eisele Thomas A , Gibson Midori Z 
Published: February 2020

Abstract
A syringe-cartridge solid-phase extraction (SPE) method was developed for determination of patulin in apple juice. A 2.5 mL portion of test sample was passed through a conditioned macroporous SPE cartridge and washed with 2 mL 1% sodium bicarbonate followed by 2 mL 1% acetic acid. Patulin was eluted with 1 mL 10% ethyl acetate in ethyl ether and determined by reversed-phase liquid chromatography using a mobile phase consisting of 81% acetonitrile, 9% water, and 10% 0.05M potassium phosphate buffer, pH 2.4. Recoveries averaged 92% and the relative standard deviation was 8.0% in test samples spiked with 50 ng/mL patulin. The method appears to be applicable for monitoring apple juice samples to meet the U.S. Food and Drug Administration compliance action level of 50 μg/kg in an industrial quality assurance laboratory environment.
Estimating Deoxynivalenol in Shelled Corn Barge Lots by Measuring Deoxynivalenol in Corn Screenings
Authors: Whitaker Thomas B , Richard John L , Giesbrecht Francis G , Slate Andrew B , Ruiz Nelson 
Published: February 2020

Abstract
To determine if deoxynivalenol (DON) is concentrated in small corn screenings, fourteen to twenty-three 1.1 kg test samples were taken from each of 10 barges of shelled corn. Each of the 181 test samples was divided into 2 components (fines and clean) using a 5 mm screen. The clean component sample rode the 5 mm screen and the fines component sample passed through the 5 mm screen. The DON concentration in fines component sample was about 3 times the DON concentration in the clean component sample. The DON in the 181 fines and clean component samples averaged 689.0 and 206.1 ng/g, respectively. Regression equations were developed to predict the DON in the barge based upon measurements of DON in the fines component sample. The ratio of DON in the lot to DON in the fines component sample was 0.359. The coefficient of variation (CV) associated with predicting the DON concentration in a lot with 359 ng/g using a 1.1 kg test sample was 47.0%. Increasing sample size to 4.4 kg reduced the CV to 23%.
Rapid Determination of Moisture and Fat in Meats by Microwave and Nuclear Magnetic Resonance Analysis
Authors: Keeton Jimmy T , Hafley Brian S , Eddy Sarah M , Moser Cindy R , McManus Bobbie J , Leffler Timothy P 
Published: February 2020

Abstract
A peer-verified method is presented for the determination of percent moisture and fat in meat products by microwave drying and nuclear magnetic resonance (NMR) analysis. The method involves determining the moisture content of meat samples by microwave drying and using the dried sample to determine the fat content by NMR analysis. Both the submitting and peer laboratories analyzed 5 meat products by using the CEM SMART system (moisture) and the SMART Trac (fat). The samples, which represented a range of products that meat processors deal with daily in plant operations, included the following: 1) fresh ground beef, high-fat; 2) deboned chicken with skin; 3) fresh pork, low-fat; 4) all-beef hot dogs; and 5) National Institute of Standards and Technology Standard Reference Material. The results were compared with moisture and fat values derived from AOAC-approved methods, 950.46 (Forced Air Oven Drying) and 960.39 (Soxhlet Ether Extraction).
Optimized Simultaneous Determination of Several Elements in Human Intestinal Caco-2 TC7 Cells by Inductively Coupled Plasma-Mass Spectrometry after Closed Vessel Microwave Digestion
Authors: Noël Laurent , Guérin Thierry , Frémy Jean-Marc , Huet Hélène , Kolf-Clauw Martine 
Published: February 2020

Abstract
A rapid procedure, based on closed vessels microwave digestion and inductively coupled plasma-mass spectrometry (ICP-MS), was evaluated to ascertain the effect of chronic exposure to cadmium on intracellular accumulation of minor and essential trace elements in cultured epithelial cells (Caco-2 TC7). For all measurements, the method of external calibration was used and 3 elements (Be, Sc, In) were selected as internal standards. Optimization procedures are discussed and results are presented for the total determination of 9 key analytes (Na, Mg, Ca, Cr, Mn, Cu, Zn, Mo, and Cd) in certified reference materials (CRMs) and 20 samples of Caco-2 TC7 cells long-term exposed to Cd. The performance characteristics of the analytical system were evaluated by calibration and linearity, limits of detection and quantitation, accuracy with spiking, trueness and repeatability with available CRMs. As a complement to the ICP-MS determinations, both available CRMs and cell samples were analyzed either by electro thermal-or flame atomic absorption spectrometry. The results were in good agreement with the ICP-MS results.
Plasma Spectrometry for Elemental Speciation and Characterization in Beverages
Authors: Meija Juris , Mounicou Sandra , Caruso Joseph A 
Published: February 2020

Abstract
A review is presented on recent applications of plasma spectrometric techniques for speciation analysis in beverages. The 3 most common ways of characterizing beverages in addition to elemental speciation are also discussed: total element analysis, isotope ratio, and statistical characterization. To date, most of the elemental characterization in beverages with plasma techniques has been performed in the statistical evaluation of wines and in teas. However, despite the increasing interest in elemental speciation, most of the plasma-based techniques in beverage studies are used for total metal detection and the full capabilities of inductively coupled plasma techniques have yet to be realized.
Fractionation and Redox Speciation of Antimony in Agricultural Soils by Hydride Generation–Atomic Fluorescence Spectrometry and Stability of Sb(III) and Sb(V) During Extraction with Different Extractant Solutions
Authors: Fuentes Edwar , Pinochet Hugo , Potin-Gautier Martine , Gregori Ida De 
Published: February 2020

Abstract
This stability of Sb(III) and Sb(V) species was studied during single extraction from soils by water. EDTA, diluted H2SO4 and H3PO4, and oxalic acid/oxalate solutions, with and without ascorbic acid, were used as stabilizing reagent of both Sb species. Antimony redox speciation in soil extracts was performed by selective hydride generation–atomic fluorescence spectrometry. Simulated extraction procedures (without soil) showed that, except in oxalate medium, Sb(III) was oxidized to Sb(V), and this reaction was avoided with ascorbic acid. Recovery studies from a spiked agricultural soil showed that no oxidation but sorption of Sb(III) occurred during the extraction process in water and H2 SO4 medium, and quantitative oxidation in EDTA and oxalate medium. With ascorbic acid, this oxidation was totally avoided in EDTA and partially avoided in oxalate solution. A new sequential extraction procedure was proposed and applied to the fractionation and redox speciation of antimony in agricultural soils, using EDTA + ascorbic acid, pH 7 (available under complexing and moderately reducible conditions); oxalic acid /oxalate + ascorbic acid (extractable in reducible conditions) and HNO3 + HCl + HF (residual fraction). The proposed extraction scheme can provide information about the availability and mobility of antimony redox species in agricultural soils.
Kinetic Spectrophotometric Determination of Josamycin in Formulations and Spiked Human Plasma Using 3-Methylbenzothiazolin-2-one Hydrazone/Fe+3 System
Authors: Al-Majed Abdulrahman A , Belal Fathalla , Khalil Nasr Y , Ibrahim Kamal E E 
Published: February 2020

Abstract
A simple kinetic spectrophotometric method was developed for the determination of josamycin in its dosage forms and spiked human plasma. The method is based on reaction of the drug with 3-methylbenzothiazolin-2-one hydrazone/ferric chloride system for a fixed time of 20 min at 70°C and measuring the produced color at 665 nm. The absorbance-concentration plot is rectilinear over the range of 5.0–30.0 μg/mL with detection limit of 1.0 μg/mL (1.2 × 10−6M). The determination of josamycin by the fixed concentration and the rate-constant methods is also feasible with the calibration equations obtained, but the fixed-time method proved to be more applicable. The procedure was successfully applied to commercial tablets. The results obtained were favorably compared with those given by reference methods. The method was further extended to the in vitro determination of josamycin in spiked human plasma. The recovery (n = 8) was 100.76 ± 3.43%. The stoichiometry of the reaction between the drug and the reagent was studied by adopting the limiting logarithmic method, and a proposal of the reaction pathway was presented.
Preparation of Peanut Butter Suspension for Determination of Peanuts Using Enzyme-Linked Immunoassay Kits
Authors: Trucksess Mary W , Brewer Vickery A , Williams Kristina M , Westphal Carmen D , Heeres James T 
Published: February 2020

Abstract
Peanuts are one of the 8 most common allergenic foods and a large proportion of peanut-allergic individuals have severe reactions, some to minimal exposure. Specific protein constituents in the peanuts are the cause of the allergic reactions in sensitized individuals who ingest the peanuts. To avoid accidental ingestion of peanut-contaminated food, methods of analysis for the determination of the allergenic proteins in foods are important tools. Such methods could help identify foods inadvertently contaminated with peanuts, thereby reducing the incidence of allergic reactions to peanuts. Commercial immunoassay kits are available but need study for method performance, which requires reference materials for within- and between-laboratory validations. In this study, National Institute of Standards and Technology Standard Reference Material 2387 peanut butter was used. A polytron homogenizer was used to prepare a homogenous aqueous Peanut Butter suspension for the evaluation of method performance of some commercially available immunoassay kits such as Veratox for Peanut Allergen Test (Neogen Corp.), Ridascreen Peanut (R-Biopharm GmbH), and Bio-Kit Peanut Protein Assay Kit (Tepnel). Each gram of the aqueous peanut butter suspension contained 20 mg carboxymethylcellulose sodium salt, 643 μg peanut, 0.5 mg thimerosal, and 2.5 mg bovine serum albumin. The suspension was homogenous, stable, reproducible, and applicable for adding to ice cream, cookies, breakfast cereals, and chocolate for recovery studies at spike levels ranging from 12 to 90 μg/g.
Harmonization of Methods for Analysis of Cholesterol Oxides in Foods—The First Portion of a Long Road Toward Standardization: Interlaboratory Study
Authors: Appelqvist Lars-Åke ,   Collaborators:, Addis Paul , Björkhem Ingemar , Olivier Bosset Jacques , Fiorenza Caboni Maria , Dutta Paresh , Grandgirard Andre , Guardiola Fransesc , Hau Lung-Bin , Holm Nielsen Jacob , Hugget Antony , Sun Hwang Lucy , Kumpulainen Jorma , McCluskey Sinead , Ohshima Toshiaki , Przbylski Roman , Sevanian Alex , Yan Pearlly 
Published: February 2020

Abstract
A compilation of literature data on the content of cholesterol oxidation products (COP) in various food products and in blood demonstrates a large variation in content in products or tissues of very similar nature when analyzed in different laboratories according to a large number of methods. The lack of validated, internationally recognized methodology with published accuracy and precision has so far hindered such assessments. Hence an interlaboratory comparision of methodologies of COP analysis was undertaken on egg yolk powders (EYP), whole milk powders (WMP), skim milk powders (SMP), and lard (L). Each product type had one fresh sample (low) and one aged (high) in COP contents. A total of 17 sets of results on WMP, 15 on SMP and EYP, and 13 on L were compared. Overall results (mg/kg sample) varied extensively: Fresh EYP 0.72–265, aged EYP 2.51–361; fresh WMP 0.02–18.1, aged WMP 0.02–26.9; fresh SMP 0.02–6.51, aged SMP &lt; 0.01–6.51; fresh L 0.18–97, aged L 4.15–452. Some results were questioned, viz., those from laboratories not indicating substantial differences between samples “low” and “high” in total COP. Others were excluded because of lack of verification of identity of gas chromato-graphic peaks by mass spectrometry. Then a more narrow range of core results (mg/kg sample) was observed: Fresh EYP 5.69–29.5 sample, aged EYP 11.8–79.0; fresh WMP 0.12–1.76, aged WMP 1.17–13.7; fresh SMP &lt; 0.30–&lt;1.21, aged SMP 0.30–2.26; fresh L 0.18–5.07, aged L 94.4–231. At a workshop discussing the results, numerous recommendations were made toward more reliable methodology for determination of COP in foods.
Improved Identification of Conjugated Linoleic Acid Isomers Using Silver-Ion HPLC Separations
Authors: Delmonte Pierluigi , Yurawecz Martin P , Mossoba Magdi M , Cruz-Hernandez Cristina , Kramer John K G 
Published: February 2020

Abstract
Silver-ion high-performance liquid chromatography (Ag+-HPLC) has been shown to be effective in the resolution of most of the isomers of conjugated octadecadienoic acids (18:2), also known as conjugated linoleic acid (CLA). The CLA isomers identified in natural fats from ruminants are a mixture of numerous positional and geometric isomers from 7,9- to 12,14–18:2. Ag+-HPLC separates both geometric (trans,trans &lt; cis/trans &lt; cis,cis) and positional CLA isomers using the mobile phase hexane/acetonitrile (99.9:0.1). The elution volumes for the CLA isomers were not only affected by the concentration of acetonitrile (in the prepared mobile phase) but also with successive runs during the day using a prepared mobile phase batch, due to the partial solubility of acetonitrile in hexane. However, this drift does not affect the relative resolution of the CLA isomers. The addition of diethyl ether to the mobile phase partly stabilizes the solvent mixture. In order to facilitate the interpretation of Ag-+HPLC chromatograms, the relative retention volumes (RRV) were calculated for each CLA isomer. Toluene was added to all the test portions and served as an estimator of dead volume, whereas the elution of the ubiquitous 9c,11t-CLA isomer was chosen as unity (1.00). Expressing the elution of all the CLA isomers as their RRV greatly helped to standardize each CLA isomer, resulting in relatively small coefficients of variation (% CV) for the trans,trans (&lt;1.5%) and cis/trans (&lt;0.5%) CLA isomers. The identification of the CLA isomers was further facilitated by synthesis of authentic CLA isomers. All the geometric CLA fatty acid methyl esters (FAME) from positions 6,8- to 13,15-CLA were commercially available or synthesized by a combination of partial hydrazine reduction of known polyunsaturated fatty acids followed by alkali isomerization, isolation of products, and further iodine-catalyzed geometric isomerization. Based on expressing the elution volume as RRV and the availability of the synthetic CLA isomers, a unique reversal of the elution order of the c/t CLA isomers was found. It is also proposed that the retention times of CLA isomers by gas chromatography (GC) should be expressed as their relative retention times (RRT) relative to methyl γ-linoleneate. The availability of CLA reference materials and the application of RRV and RRT to Ag+-HPLC and GC separations, respectively, will greatly improve in the identifications of CLA isomers.
Colorimetric Assay of Propranolol Tablets by Derivatization: Novel Application of Diazotized 4-Amino-3,5-Dinitrobenzoic Acid (ADBA)
Authors: Idowu Olakunle S , Adegoke Olajire A , Olaniyi Ajibola A 
Published: February 2020

Abstract
A novel colorimetric assay of propranolol tablets has been developed. The assay is based on chemical derivatization (aromatic ring derivatization technique) using diazotized 4-amino-3,5-dinitrobenzoic acid (ADBA) as the chromogenic derivatizing reagent and resultant formation of azo dyes. Optimization studies established an optimal reaction time of 5 min at 30°C after mixing on a Vortex mixer the drug/reagent mixture for 10 s. A new absorption maximum (λmax) was found at 470 nm, which was selected as the analytical wavelength. The assays were linear over 1–8 μg/mL propranolol, and the reaction occurred by a 1:1 reagent/drug stoichiometric ratio. The developed method has a low limit of detection of 0.76 μg/mL and is reproducible. It has been applied successfully to the assay of propranolol tablets and is of equivalent accuracy (p &gt; 0.05) with the official (British Pharmacopoeia) ultraviolet spectrophotometric method. The new method has the main advantage of using more affordable instrumentation and could be applied to the in-process quality control of propranolol tablets.