bluuebunny/crossref_metadata_2025_split huggingface dataset:
Liquid Chromatographic Methods for Determination of Trazodone and Related Compounds in Drug Raw Materials
Authors: Beaulieu Normand , Sears Roger W , Lovering Edward G 
Published: February 2020

Abstract
Liquid chromatographic methods for the determination of trazodone and 10 related compounds are described. An octylsilane column was used with a mobile phase of tetrahydrofuran–methanol–acetonitrile–0.5% trifluoroacetic acid (6 + 2 + 6 + 27) and detection at 248 nm. Minimum quantifiable amounts of the related compounds were less than 0.05% based on coefficients of variation of less than 10%. Total impurities in 5 raw drug materials were less than 1 %.
Determination of Sulfadimethoxine and Ormetoprim Residues in Channel Catfish Fillets After Treatment with Romet and Evaluation of a Commercially Available Rapid Diagnostic Test for Drug Residues in Fish Fillets
Authors: Milner Nicholas P , Johnson Michael R , Perry Kim J 
Published: February 2020

Abstract
Sulfadimethoxine (SDM) and ormetoprim (OMP) residues were determined in catfish fillets after treatment with Romet. A liquid chromatographic (LC) method capable of simultaneously detecting SDM and OMP at 0.05–40 ppm was used. The recoveries were 92% for SDM and 108% for OMP. The intra- assay variabilities were determined for SDM and OMP at fortification levels of 0.05–40 ppm, and a coefficient of variation (CV) of less than 10% was achieved at all levels. The interassay variations were determined at fortification levels of 0.1 ppm (CVs: SDM, 6.4%; OMP, 4.9%) and 1.0 ppm (CVs: SDM, 2.8%; OMP, 3.5%). SDM and OMP residues in catfish fillets were rapidly depleted after treatment with Romet. By day 2 posttreatment, SDM and OMP were essentially nondetectable. The use of an enzyme-linked immunoassay (ELISA)-based rapid diagnostic test to determine SDM and OMP in catfish fillets was evaluated. An assay procedure to adapt the test for residues in tissue samples was developed. SDM and OMP were extracted from ground catfish fillet with methanol–water (80 + 20, v/v); the extract was diluted with buffer and filtered, and the filtrate was then tested with an EZ Screen test card. The effectiveness of the rapid test assay to detect SDM residues at levels above the U.S. Food and Drug Administration tolerance (0.1 ppm) was verified with fillets from Romet-treated catfish. All samples with residues at &gt;0.1 ppm were identified correctly by the test. The results indicate that the diagnostic test could be used as a rapid method for monitoring Romet residues in catfish.
Depletion of Residues from Milk and Blood of Cows Dosed Orally and Intravenously with Sulfamethazine
Authors: Paulson Gaylord D , Feil Vernon J , Zaylskie Richard G , Giddings John M , Slanger William D 
Published: February 2020

Abstract
Cows were dosed orally (n=4) or intravenously (n = 4) with sulfamethazine [sulmet; 4-amino-N(4,6-dimethyl-2-pyrimidinyl)benzenesutfonamide] for 5 consecutive days (220 mg/kg of body weight on day 1 and 110 mg/kg on days 2–5). The concentrations of sulmet, N4-acetylsulfamethazine (Ac-sulmet), and the N4-lactose conjugate of sulfamethazine (lac-sulmet) were measured in milk and blood collected at 24 h intervals after the last doses of sulmet were given. The method of analysis included (1) spiking of samples with known amounts of 13C6-labeled reference compounds, (2) resolution of the 3 compounds by reversed- phase chromatography, (3) hydrolysis of lac-sulmet, (4) treatment with diazomethane to yield N1-methyl derivatives, and (5) gas chromatography/mass spectrometry. The ratios of intensities of selected mass spectral ions containing 12C6 and the corresponding ions containing 13C6 were used for residue quantitation. Sulmet, which was always the most abundant residue in the blood, decreased to less than 100 ppb 4 days after the last doses were given and to less than 10 ppb 7 days after the last doses. The concentrations of sulmet in milk were approximately one fifth the concentrations of sulmet in blood. The concentrations of lac-sulmet and Ac-sulmet in milk were lower than the concentrations of sulmet in milk.
Determination of Clenbuterol in Cattle, Sheep, and Swine Tissues by Electron Ionization Gas Chromatography/Mass Spectrometry
Authors: Wilson Roger T , Groneck Joseph M , Holland Kathleen P , Carolyn Henry A 
Published: February 2020

Abstract
A gas chromatographic/mass spectrometric procedure is described for the quantitation and confirmation of clenbuterol residues from cattle, sheep, and swine tissues. After liquid–liquid extraction and derivatization with phosgene in an aqueous pH 10.1 buffer, the cyclic oxazolidone derivative is quantitated with a clenbuterol analogue as internal standard (NAB-760 CI). Confirmation is accomplished by comparison of ion ratios with those of a pure synthesized standard of clenbuterol oxazolidin-3-one obtained by selected ion monitoring, electron ionization gas chromatography/mass spectrometry on a benchtop instrument. Statistical information based on a series of standard curves for fortified tissues is included to describe method performance. Ion ratio variations were under 15%, and coefficients of variation for spiked tissue standard curves were above 0.997. Recoveries averaged 87.1 ± 6.6% for liver tissues across all 3 species and 67.1 ± 3.8% for muscle tissue across all 3 species.
Selection of a Simple and Sensitive Method for Detecting Zearalenone in Corn
Authors: Quiroga Nora M , Sola Inés , Varsavsky Edith 
Published: February 2020

Abstract
A simple, rapid, and sensitive method for determining zearalenone in corn was selected. The toxin was extracted from 50 g test portions with 180 mL acetonitrile and 20 mL 4% KCl solution. A portion of the extract was defatted with isooctane. The acetonitrile extract was cleaned up with 20% lead acetate solution. The zearalenone was partitioned into toluene. The toluene solution was dried, and the residue was redissolved in benzene. The toxin was determined by thin-layer chromatography with silica gel plates and chloroform–acetone (9 +1) as the developing solvent. The overall average recovery of zearalenone from corn was 97%. The limit of detection was 50 μg/kg; this limit may be lowered by using fast violet B salt as spray reagent. The method was compared with 2 previous methods that determine zearalenone in biologically contaminated corn.
Analysis of Wortmannin (H-1) by Liquid Chromatography and Gas Chromatography
Authors: Xu Yichun , Mirocha Chester J 
Published: February 2020

Abstract
An analytical method for detection of wortmannin in corn kernels was developed based on liquid chromatography (LC) and gas chromatography (GC). The sample was extracted with ethyl acetate, subjected to cleanup procedures on Sep–Pak silica gel column, and eluted with dichloromethane–chloroform (1+1). Analysis was made either by LC or GC. The limit of detection was 2.5 by LC and 25 ng/g by GC. The recovery from corn by LC at 2.5, 5.0, 10, 25, 50, 100, 250, 500, and 1000 ng/g was 89 (11.5 sd), 72 (2.6), 69 (7.4), 90 (7.5), 78 (9.3), 72 (6.1), 84 (17.5), 82 (11.5), and 76 (12.9), respectively. Recovery measured by GC at 25, 50, 100, 250, 500, and 1000 ng/g was 78 (12.5), 72 (14.0), 78 (3.8), 69 (2.6), 74 (16.9) and 81 (8.3)%, respectively. The average recovery was 79% by LC and 75% by GC.
Analysis by Liquid Chromatography of Fusarochromanone (TDP-1) Added to Corn and Wheat
Authors: Xu Yichun , Mirocha C J , Xie W 
Published: February 2020

Abstract
An analytical method was developed for the detection of fusarochromanone (TDP-1) in com and wheat by liquid chromatography. Extraction was done with methanol-water-ammonium hydroxide (90 + 10 + 2), and cleanup was by elution through a silica Sep-Pak cartridge. The limit of sensitivity of TDP-1, detected on the basis of its fluorescence properties, is 200 pg, whereas the detection limit of the method for corn and wheat is 5 ng/g. The average recoveries of TDP-1 added at 5,25,100,500, and 1000 ppb were 86% for corn and 83% for wheat. Confirmation was done by thin-layer chromatography.
Determination of Methyl 2-Benzimidazolecarbamate in Bulk Fruit Juice Concentrates by Competitive-Inhibition Enzyme Immunoassay
Authors: Bushway Rodney J , Young Barbara E S , Paradis Lance R , Perkins Lewis B , Martin Susan K , Brown Myrna P 
Published: February 2020

Abstract
A polyclonal enzyme immunoassay (EIA) was used to quantitate methyl 2-benzimidazolecarbamate (MBC or carbendazim), a degradation product of benomyl, in bulk fruit juice concentrates. These concentrates are used by industrial producers to prepare juice or juice concentrates sold in supermarkets. Total sample analysis time was less than 18 min without cleanup or 35 min with cleanup. As many as 8 samples can be analyzed simultaneously, with a limit of quantitation of 10 ppb. The assay’s dynamic range ran from 0.5 to 20 ppb MBC but was best from 0.5 to 10 ppb. Intra-assay coefficients of variation (CVs) varied from 4.0 to 13% for standards and from 4.1 to 26% for samples. Inter-assay CVs varied from 4.5 to 47% for standards and 5.6 to 22% for samples. Average recovery of several juice concentrates spiked at 10 to 290 ppb was 97%. A total of 140 juice concentrates comprising 20 different kinds of juice were analyzed by 2 EIA methods and one liquid chromatographic (LC) procedure. MBC-positive samples gave the following correlation coefficients: 0.954 for EIA without cleanup vs LC, 0.956 for EIA with cleanup vs LC, and 0.978 for EIA with cleanup vs EIA without cleanup. MBC concentrations in MBC-positive juice samples ranged from 5 to 2960 ppb.
Determination of Inorganic Anions in Water by Ion Chromatography: Collaborative Study
Authors: Edgell Kenneth W , Longbottom James E , Pfaff John D 
Published: February 2020

Abstract
The U.S. Environmental Protection Agency (U.S. EPA) and the American Society for Testing and Materials (ASTM) conducted a joint collaborative study validating an ion chromatographic method for determination of inorganic anions (U.S. EPA method 300.0A and the equivalent proposed revision to ASTM method D4327). This study was conducted to determine the mean recovery and precision of analyses for bromide, chloride, fluoride, nitrate, nitrite, orthophosphate, and sulfate in reagent water, drinking water, and wastewater. The study design was based on Youden's nonreplicate plan for collaborative tests of analytical methods. The test waters were spiked with the anions at 6 concentration levels, prepared as 3 Youden pairs. The 22 volunteer laboratories were instructed to dilute 10 mL sample concentrate to 100 mL test water. A measured volume of sample (20-200 μL) was injected into an ion chromatograph equipped with a guard column, anion exchange column, and a chemical micromembrane suppression device. The anions were then separated using 1.7 mM sodium bicarbonate and 1.8 mM sodium carbonate, and measured by a conductivity detector. Submitted data were evaluated using U.S. EPA's IMVS computer program, which follows ASTM D2777-86 statistical guidance. U.S. EPA method 300.0A and ASTM method D4327 were judged acceptable for measurement of the above anions (except sulfate) at concentrations ranging from 0.3 to 25 mg/L and sulfate concentrations from 2.9 to 95 mg/L. Mean recoveries for the 7 anions from all matrixes, as estimated from the linear regression equations, ranged from 95 to 104%. At concentrations above 2-6 mg/L for bromide, fluoride, nitrate, nitrite, and orthophosphate, and above 24 mg/L for sulfate, the overall and single-analyst relative standard deviations were less than 10 and 6%, respectively. As concentrations decreased, precision became more variable. The relative standard deviations of results for chloride were slightly higher than the other anions, especially in matrixes with high chloride background. Analysis of Variance (ANOVA) tests at the 95% confidence interval indicated a statistically significant matrix effect for chloride, nitrite, and nitrate analyses in drinking water compared to analyses in reagent water. Because these matrix effects were caused by the spiking process and not the drinking water itself, the ANOVA determination was not considered to be of practical significance.
Capillary Gas Chromatographic Determination of Thiabendazole in Citrus and Apple Juices
Authors: Oishi Mitsuo , Onishi Kazuo , Kano Itsu , Nakazawa Hiroyuki , Tanabe Shinzo 
Published: February 2020

Abstract
A rapid and simple procedure for the determination of thiabendazole (TBZ) residue in citrus and apple juices is described. A juice sample is made basic with 2M NaOH and applied to a disposable Extrelut prepacked column. TBZ is eluted with hexane–ethyl acetate (3 + 1) from the column. The eluate is evaporated to dryness under reduced pressure and then dissolved in an internal standard solution. TBZ is monitored without derivatization by capillary gas chromatography with nitrogen-phosphorus detection. The recoveries of TBZ added to fruit juices at 0.05-1.0 μg/g were 90-96%. The limit of detection of the method for TBZ was 0.01 μg/g. The proposed method is rapid, simple, and sensitive and is applicable to the determination of TBZ in commercial fruit juices.
Liquid Chromatographic Determination of Nifursol in Concentrates, Premixes, and Finished Turkey Feeds
Authors: De Vries Ellen Jan , Bas Richard C , Kuil Henny 
Published: February 2020

Abstract
A specific liquid chromatographic method was developed for determination of nifursol in premixes and turkey feeds. Nifursol is extracted from test sample into tetrahydrofuran. Butylhydroxytoluene is added to prevent degradation of nifursol. The extract is diluted with tetrahydrofuran–water (50 + 50, v/v); an aliquot is injected onto a Zorbax ODS column. The mobile phase is water-acetonitrile (525 + 475, v/v) adjusted to an apparent pH of 3.5 with formic acid and ammonia. The wavelength of detection is 380 nm. The system can separate nifursol from dimetridazole and ronidazole. The method is specific; has linearity of more than one order of magnitude; and has a limit of quantitation in the 1–2 ppm range. Recovery averaged 98% or more, and the reproducibility had a coefficient of variation of better than 2.5% in pelleted feed.
Liquid Chromatographic Determination of Diclazuril in Premix and Supplemented Feed: Interlaboratory Study
Authors: Fontaine Andre , Haustraete Karel 
Published: February 2020

Abstract
Diclazuril, Janssen Research Compound R 64433 (Clinacox), is analyzed by liquid chromatography (LC). Compound R 062646, with a structure analogous to that of diclazuril, is used as internal standard. The drug is extracted from feed with acidified methanol. Diclazuril is then isolated by solid-phase extraction (SPE) with a cartridge containing a C18 phase. The eluate is evaporated, and the residue is redissolved in dimethylformamide. An aliquot is injected onto a reversed-phase ODS LC column, and the drug quantitated at 280 nm with a UV detector. Peak areas are obtained at the retention times corresponding to the internal standard and diclazuril. The quantity of active ingredient is determined by comparing the ratio of the peak height of diclazuril to that of internal standard in the sample with the same ratio in a single calibration solution. SPE is not necessary for the analysis of premixes. Eleven laboratories participated in the collaborative study. Laboratories were provided with 2 samples of premixes and 3 samples of feed for poultry. Feed sample K1 was sent to only 6 laboratories. The reproducibility relative standard deviations (RSDRS) were 7.38 and 7.53% for the 2 premixes and 9.67,13.65, and 18.61% for the 3 samples of supplemented feed.
Determination of Chlorobiphenyls in Cleaned-Up Seal Blubber and Marine Sediment Extracts: Interlaboratory Study
Authors: Boer Jacob De , Der Meer Jaap Van , Reutergårdh Lars , Calder John A 
Published: February 2020

Abstract
An interlaboratory study on the determination of individual chlorobiphenyl congeners (CBs) in cleaned-up seal blubber and marine sediment extracts was organized by the International Council for Exploration of the Sea, the Intergovernmental Oceanographic Commission, and the Oslo and Paris Commissions, as the second part of a stepwise-designed interlaboratory study on the determination of CBs in marine media. Fifty-eight laboratories from 16 countries participated in this exercise, which involved the determination of 10 CBs in a standard solution, a cleaned-up seal blubber extract, and a cleaned-up marine sediment extract. Suggestions were given for instrument optimization. Standard errors of 1.16–1.17 for the standard solution, 1.20–1.33 for the seal blubber extract, and 1.31–1.56 for the sediment extract were obtained for CBs 52,101,118,138,153, and 180 by all laboratories with the exception of the laboratories giving consistently outlying results. The results for CBs 28,31,105, and 156 showed larger standard deviations. The 2 major difficulties for participants in this exercise were correct preparation of a calibration solution and chromatographic separation. The results of the sediment analysis showed a complete lack of agreement. It is recommended that, prior to the organization of the third part of this study, participants should install gas chromatographic columns with minimum lengths of 50 m and maximum internal diameters of 0.25 mm and should prepare calibration solutions from solids of known purity.
Radionuclides in Domestic and Imported Foods in the United States, 1987–1992
Authors: Cunningham William C , Anderson David L , Baratta Edmond J 
Published: February 2020

Abstract
Findings from the U.S. Food and Drug Administration’s Radionuclides in Foods program are summarized for foods collected between October 1,1986, and September 30,1992. Concentrations of radionuclide activity in the Total Diet Study and reactor-survey foods were in Range I or low in Range II of the surveillance and control recommendations of the Federal Radiation Council; no control actions were suggested. Dietary intake of 90Sr continued the general decline observed since 1961. Approximately 2600 test portions of imported foods were analyzed for contamination associated with the Chernobyl nuclear accident. Concentrations of radionuclide activity were below limits of detection for the vast majority of the imported food test portions but were above the levels of concern for 23 portions. Since 1986, the fraction of imported food test portions having measurable amounts of contamination has steadily declined, as have the average concentrations of radionuclide activity; however, contamination is still occasionally found. Continued monitoring of both domestic and imported foods is planned.
Liquid Chromatographic Determination of Cromolyn Sodium and Related Compounds in Raw Materials
Authors: Duhaime Randy M , Rollins Lorna K , Gorecki Dennis J K , Lovering Edward G 
Published: February 2020

Abstract
Liquid chromatographic methods for the assay of cromolyn sodium and 3 related compounds were developed. The methods, which differ only in the composition of the mobile phase, use an octadecylsilane bonded-phase column and an acetonitrile–water–cetyltrimethylammonium bromide mobile phase. Minimum quantitatable amounts of the related compounds were less than 0.05%; assay method precision was better than 1 %. Impurity levels in raw material samples from 4 manufacturers were less than 0.1 %.
Liquid Chromatographic Determination of Amiodarone Hydrochloride and Related Compounds in Raw Materials and Tablets
Authors: Lacrok Pauline M , Curran Norman M , Sy Wing-Wah , Goreck Dennis K J , Thibault Pierre , Blay Pearl K S 
Published: February 2020

Abstract
A liquid chromatographic method for the determination of amiodarone hydrochloride and 10 related compounds in drug raw material and for assay of drug in tablets was developed. The method specifies a 3 jxm Hypersil nitrile column (150 × 4.6 mm), a mobile phase of 1 + 1 acetonitrile–ammonium acetate buffer (0.1 M adjusted to pH 6.0 with 0.1 M acetic acid), a flow rate of 1 mL/min, and detection at 240 nm. The lower limit of quantitation of the related compounds is 0.02% or less. Drug contents in 2 raw material samples were 100.1 and 99.9% and ranged from 98.2 to 99.4% in 3 tablet formulations. Impurity levels in 2 samples of raw material from different manufacturers were ca 0.4%. The presence of 3 of the known related compounds in these samples was confirmed by liquid chromatographymass spectrometry. The method applied to raw materials was evaluated by a second laboratory and found to be satisfactory.
Detection of Salmonella in Dry Foods Using Refrigerated Pre-Enrichment and Enrichment Broth Cultures: Summary of Collaborative Study
Authors: D’Aoust Jean-Yves , Sewell Anne M , Greco Paula 
Published: February 2020

Abstract
A collaborative study was conducted to compare the productivity of refrigerated pre-enrichment and enrichment broth cultures with the U.S. Food and Drug Administration culture methods for detection of Salmonella. The refrigerated pre-enrichment and selective enrichment broth culture methods for detection of Salmonella in dry foods have been adopted first action by AOAC INTERNATIONAL.
Extraction of Aflatoxins from Naturally Contaminated Peanuts with Different Solvents and Solvent/Peanut Ratios
Authors: Cole Richard J , Dorner Joe W 
Published: February 2020

Abstract
A study was conducted to compare the extraction efficiencies of aflatoxins (B1, B2, G1, and G2) from low, medium, and high concentrations (approximately 10,100, and 1000 ppb, respectively) of naturally contaminated peanut samples by using different solvents and solvent-to-peanut sample ratios. Solvents used were 80:20 methanol/water at 2:1,3:1, and 5:1 solvent to sample ratios; 60:40 methanol/water at 5:1 solvent to sample ratio; and 90:10 acetonitrile/water at 2:1 and 4:1 solvent to sample ratios. The solvents 80:20 methanol/water at a 3:1 ratio of solvent to sample and 90:10 acetonitrile/water at a 2:1 ratio were consistently more efficient than all other solvents, regardless of the aflatoxin concentration. The solvent 90:10 acetonitrile/water at a 4:1 solvent-to-sample ratio was consistently the least efficient regardless of aflatoxin concentration based on analytical results with liquid chromatography (LC). The results are relevant in selecting an appropriate extraction solvent for use at peanut grading points.
Comparison of Mercury and Copper Based Catalysts in the Kjeldahl Determination of Nitrogen in Meat and Meat Products: Collaborative Study
Authors: Price Cindy G , Webb Neil B , Smith Wertice J , Marks Harry M , Yoffe Aron M 
Published: February 2020

Abstract
A copper catalyst for use in AOAC Method 928.08, Nitrogen in Meat, Kjeldahl Method, was subjected to a collaborative study in which it was compared to the standard mercury catalyst. Nine laboratories (including one author’s laboratory) performed blind duplicate determinations of the protein content of 4 samples from each of 6 products (ground beef, canned ham, smoked ham, pork sausage, cooked sausage, and dry cured ham). On the average, protein concentrations obtained with the copper catalyst were lower than those obtained with the mercury catalyst by approximately 1% of the protein content of the meat. For example, with a sample containing 15% protein, the results obtained with mercury would be expected to be 0.15% higher than those obtained with copper. This difference is within the reproducibility standard deviations of the methods. The repeatability standard deviation with copper was on the average approximately 17% larger than that obtained with mercury, but the reproducibility standard deviations for the 2 procedures were not, statistically, significantly different. The Kjeldahl method for nitrogen determination in meat and meat products using copper catalyst has been adopted first action by AOAC INTERNATIONAL.