bluuebunny/crossref_metadata_2025_split huggingface dataset:
SIREN: Data Base Approach to Scientific Information Handling in the Bureau of Foods, Food and Drug Administration
Authors: Brindza George A , Mccann Adriana 
Published: February 2020

Abstract
The Bureau of Foods has developed the Scientific Information Retrieval and Exchange Network (SIREN) to provide a modern method of records management and an automated cross-referenced subject index for accurate and comprehensive information retrieval. Authorized Bureau personnel may access SIREN's 200 000 references directly on distributed, interactive on-line terminals or indirectly through searches conducted by the SIREN Document Control Center.
Comparison of Three Methods for Determination of Crude Protein in Meat: Collaborative Study
Authors: Suhre Francis B , Corrao Paul A , Glover Angeline , Malanoski Anthony J ,   Collaborators:, Cannon L D , Dummett T , Funk R , Glover A , Heavner G , Hoover R L , Latham M , Long F L , Martini J H , McGee K , Morris W C , Oberste W , Okamoto M , Pakrasi B , Pasquarella P J , Reiser J , Sorensen L , Lovestrand J , Taylor M , Trombella B , Warden S R , Wayo C , Wiebke R , Woods W 
Published: February 2020

Abstract
A study was designed to compare the Kjel-Foss automated macro-Kjeldahl method and a block digestion- steam distillation method. The official AOAC Kjeldahl method was used as a reference procedure. Six products with a crude protein range of 10-30% were analyzed by 23 laboratories. Five laboratories analyzed the samples by the official AOAC method, 8 laboratories used the automated Kjel-Foss method, and 11 laboratories used the block digestion with steam distillation method. Standard deviations for each product and each method for both repeatability and reproducibility are given. The block digestion- steam distillation method has been adopted official first action.
Determination of Chloride Concentration in Cheese: Collaborative Study
Authors: Poortvliet L J , Horwitz William 
Published: February 2020

Abstract
Three samples of ground Gouda cheese containing 1-2% chloride were analyzed by 7 laboratories by 3 methods: oxidation with KMnO4 and HNO3 followed by a Volhard titration; the same but with filtering off the precipitated AgCl before back-titration; and the general potentiometric method without ashing or oxidation. The data were analyzed by ISO statistics (ISO-R 5725) and by AOAC statistics (Youden), the major differences being the rejection of different values as outliers and in the statement of the precision parameters. The within-laboratory variability (repeatability) is comparable for all 3 methods; the between-laboratory variability (reproducibility) is comparable for the Volhard method with filtration and the potentiometric methods, but the direct Volhard method is inferior. Because of its generality and simplicity, the potentiometric method has been adopted official first action; the Volhard method with filtration has been reinstated official final action as an alternative.
Determination and Thin Layer Chromatographic Confirmation of Identity of Aflatoxins B1 and M1 in Artificially Contaminated Beef Livers: Collaborative Study
Authors: Stubblefield Robert D , Kwolek William F , Stoloff Leonard ,   Collaborators:, Fremy J M , Greer J I , Juszkiewicz T , Kronert W , Meyer C J , Patterson D S P , Pulzhofer K , Richard J L , Saito Y , Schuller P L , Sizoo E A , Trucksess M W , Tuinstra L G M Th , van Egmond H P , Wilson D 
Published: February 2020

Abstract
An international collaborative study involving 13 laboratories was conducted to test methods for the determination and thin layer chromatographic (TLC) confirmation of identity of aflatoxins B1 and M1 in beef liver. For the determination, each collaborator furnished fresh or frozen beef liver. Samples were artificially contaminated by adding solutions containing various concentrations of aflatoxins B1 and M1 (0.032-0.69 ng/g). Two TLC confirmation methods were tested with extracts obtained from the determination. Two measurement methods using 2-dimensional TLC were evaluated. In the first, sample extracts were compared directly with B1 and M1 standards on TLC plates; in the second, internal standards plus sample extracts were compared with Bi and M1 standards on the plates. Average within-laboratory coefficients of variation (CV) for the direct method were 26% for B1 and 26% for M1 compared with 24 and 26%, respectively, for the internal standard method. The average between-laboratory CV values were 39% for Bi and 41% for M1 by the direct method and 36% for B1 and 39% for M1 by the internal standard method. Recoveries ranged from 64 to 90% for Bi and from 72 to 86% for M1. These data indicate that the more convenient direct method was sufficient, and internal standards were unnecessary. An analysis of variance was calculated from combined sample data to determine components of variance. The within-laboratory CV values were 27.0 and 32.3% for B1 and M1, respectively, and the between-laboratory CV values were 47.1 and 53.2%, respectively. Both TLC confirmation methods gave satisfactory results and have been adopted official first action, along with the determination method.
Spectrophotometric and Titrimetric Determination of Certain Adrenergic Drugs, Using Organic Brominating Agents
Authors: Walash Mohamed I , Ouf A Abou , Salem Fatma B 
Published: February 2020

Abstract
New oxidimetric titrants, bromamine T, dibromohydantoin, N-bromophthalimide, and N-bromosuccinimide, were applied to the determination of ephedrine.HCl, norephedrine.HCl, and methyldopa. Direct potentiometric and visual indicator titration methods as well as back-titration procedures have been developed for their determination. Oxidation of ephedrine and norephedrine produces benzaldehyde, which is extracted from pH 11.0 phosphate buffer with ether or hexane and determined spectrophotometrically at 242 nm. Beer’s law is obeyed in the concentration range from 0.2 to 2 mg ephedrine.HCl and from 0.15 to 1.9 mg norephedrine. HCl. Methyldopa is determined titrimetrically and spectrophotometrically. In addition, this drug acts as a self-indicator: Solutions change from colorless to red, which gradually disappears with continuous addition of brominating agent and shaking. Phosphate buffer is used to produce adrenochrome, characterized by its pink color which can be measured at 485 nm in a working range from 40 to 650 μg.
High Performance Liquid Chromatographic Analysis of Impurities and Degradation Products of Methoxychlor
Authors: West Paul R , Chaudhary Sunil K , Branton Graham R , Mitchell Reginald H 
Published: February 2020

Abstract
Both reverse and normal phase high performance liquid chromatographic techniques have been applied to the analysis of technical methoxychlor. Facile detection of high molecular weight components yields information that is complementary to the gas chromatographic analysis of the technical pesticide and environmentally altered samples.
The Infant Formula Industry, the Infant Formula Act of 1980, and Quality Control
Authors: Gelardi Robert C 
Published: February 2020

Abstract
Throughout the months following the discovery of the low-chloride problem in infant formula, the industry undertook independent and voluntary measures to ensure the compositional quality of formulas. Members of the Infant Formula Council reviewed industry procedures, practices, and policies, and submitted a detailed description of its quality control and clinical testing procedures to the Food and Drug Administration. New product concepts and product reformulation proposals are based on medical and nutritional findings, on changes in medical concepts for nutritional support, on availability of improved nutrient sources, or on improved ingredients or processing technologies. Quality control is maintained throughout the manufacturing process through inspection of raw materials, analysis of major and minor constituents, equipment and process controls, and continuous product monitoring. However, despite cooperation of the infant formula industry with FDA and Congress during the development of the infant formula bills, the proposed document was too rigid and did not take into account that manufacturing methods of a given manufacturer often vary for the same product, for different products, and on different production equipment. The statistical criteria established uneven and inconsistent requirements for various manufacturers. Congress did not forsee that the proposed regulatory procedures would significantly affect industry.
Limitations in Protection Afforded by Gloves in Laboratory Handling of Aflatoxins
Authors: Castegnaro Marcel , Van Egmond Hans P , Paulsch Walter E , Michelon Jocelyne 
Published: February 2020

Abstract
The permeability of latex and vinyl laboratory gloves by aflatoxins in chloroform or dimethyl sulfoxide (DMSO) has been investigated. Latex gloves provide good protection against permeation by aflatoxins in DMSO, but aflatoxins in chloroform permeate all types of laboratory gloves. If gloves are contaminated when aflatoxins in chloroform are handled, an immediate change of gloves is recommended.
Identification of Frozen, Cooked Shellfish Species by Agarose Isoelectric Focusing
Authors: Wiggin Kate , Krzynowek Judith 
Published: February 2020

Abstract
A modification of the AOAC official method for generic identification of cooked and frozen crabmeat was investigated in an experiment in which the cooked meats of a variety of shellfish were identified. The modification, substituting agarose for polyacrylamide as the gel medium, has many advantages over the official method, including ease of gel preparation, nontoxic reagents, and rapid focusing. Results indicate that the modified method is easier to use and that identifications of cooked shellfish species can be made as readily as with the current AOAC method.
Liquid Chromatographic Analysis of Samples Containing Cocaine, Local Anesthetics, and Other Amines
Authors: Noggle F Taylor , Clark C Randall 
Published: February 2020

Abstract
A liquid chromatographic procedure is described the for separation of cocaine, local anesthetics, and other amines often encountered in cocaine look-alike preparations. Amines such as ephedrine, pseudoephedrine, and phenylpropanolamine are identified following derivatization with phenylisothiocyanate. The isocratic, reverse phase method uses dual wavelength detection at 254 and 280 nm.
Gas-Liquid Chromatographic Method for Determining 1,4-Dioxane in Cosmetics
Authors: Black Donald B , Lawrence Robert C , Lovering Edward G , Watson James R 
Published: February 2020

Abstract
A gas-liquid chromatographic procedure has been developed for the quantitation of 1,4-dioxane in various cosmetic products including lotions, cleansers, skin creams, make-ups, and shampoos. The impurity is extracted into an aqueous phase followed by column cleanup to remove nonpolar interferents. 1,4-Dioxane is partitioned into toluene, passed through an extraction tube to remove water and other polar compounds including organic dyes, concentrated by adsorption onto silica, further purified by washing with dichloromethane, and eluted with acetonitrile for injection into the gas chromatograph. The mean recovery of 1,4-dioxane from 51 cosmetic products, determined by spiking, was 63%. The limit of detectability is about 0.5 ppm and the minimum quantifiable level is about 2 ppm. The identity of 1,4-dioxane is confirmed by mass spectrometry.
Elimination of Sodium Chloride Interference During High Pressure Liquid Chromatographic Determination of Sugars
Authors: Devries Jonathan W , Chang Henry L , Heroff John C , Johnson Kevin D 
Published: February 2020

Abstract
A method is described to eliminate the potential interference of sodium chloride found in some food samples, which occurs during high pressure liquid chromatographic (HPLC) analysis of sugars, using certain bonded aminopropyl columns. The column is tested, and if an interference is present, it is removed by washing the column with a solution of tetraethylenepentamine in mobile phase. HPLC separation and quantitation of the sugars are essentially the same as before washing; however, sodium chloride no longer interferes with any of the sugars being analyzed.
Presumptive Screening Test for Seminal Acid Phosphatase Using Sodium Thymolphthalein Monophosphate
Authors: Seiden Howard , Duncan George T 
Published: February 2020

Abstract
The use of sodium thymolphthalein monophosphate for presumptive seminal acid phosphatase testing is discussed. Recent evidence reveals that the dye (o-dianisidine) used in conjunction with α-naphthyl phosphate for seminal acid phosphatase testing is a carcinogenic hazard. Numerous tests for seminal acid phosphatase were conducted with swabs from sexual assault kits to compare both substrates. Results of tests using sodium thymolphthalein or α-naphthyl phosphate correlated exactly. Sodium thymolphthalein is an effective alternative for preliminary seminal fluid analysis because of its high degree of selectivity and stability, and because it eliminates the potential health hazard.
High Performance Liquid Chromatographic Determination of Selected Gas Phase Carbonyls in Tobacco Smoke
Authors: Manning Delmar L , Maskarinec Michael P , Jenkins Roger A , Marshall Amos H 
Published: February 2020

Abstract
Low molecular weight gas phase carbonyls in tobacco smoke are separated as 2,4-dinitrophenylhydrazones and determined by reverse phase high performance liquid chromatography. A trapping procedure is used whereby the gas phase carbonyls are reacted with the derivatizing reagent in a closed system. The deliveries of acetaldehyde and acrolein are compared with published data. In addition, propionaldehyde and acetone deliveries of selected cigarettes are reported.
Preparation and Characterization of Acid Dehydration Products of Aflatoxicol
Authors: Lau Hon P , Chu Fun S 
Published: February 2020

Abstract
Treatment of aflatoxicol with acid resulted in the formation of dehydrated derivatives with the 2,3 double bond either hydrated or unaffected. Chromatographic and physicochemical analyses of the purified derivatives revealed that hydration of the 2,3 double bond of aflatoxicol with simultaneous dehydration occurred when sulfuric acid was used. When a weaker acid such as chloroacetic acid was used, no hydration occurred, and 2 isomeric forms of the dehydrated aflatoxicol were obtained. Chicken embryo assay and the Ames test revealed that dehydrated aflatoxicols were much less toxic and mutagenic than aflatoxicol. A mechanism for the dehydration of aflatoxicol is proposed.
Rapid Thin Layer Chromatographic Determination of Zearalenone in Corn, Sorghum, and Wheat
Authors: Gimeno Alberto 
Published: February 2020

Abstract
Arapid method is described for determining zearalenone in corn, sorghum, and wheat. The myco-toxin is extracted with a mixture of acetonitrile and 4% KC1 in HC1. The extract is cleaned up with iso- octane, evaporated, and redissolved in chloroform. Zearalenone is separated by thin layer chromatography; identity is confirmed with various developing solvents and spray reagents. Zearalenone is then quantitated by the limit detection method. The minimum detectable concentration is 140-160 μg/kg when aluminum chloride solution is used as spray reagent, and 85-110 μg/kg when Fast Violet B salt is used as spray reagent
Extraction and Thin Layer Chromatography of Aflatoxin Bi in Mixed Feeds
Authors: Shannon Gail M , Shotwell Odette L , Kwolek William F 
Published: February 2020

Abstract
A method was developed for the determination of aflatoxin B1 in commercially prepared feeds. The method incorporates methylene chloride and citric acid solution extraction, cleanup on a small silica gel column, and thin layer chromatography for quantitation. Commercial turkey starter, catfish chow, medicated pig starter, broiler finisher, rabbit chow, horse feed, rat chow, and dog chow were investigated. The feeds were spiked with naturally contaminated corn at 4 different levels of aflatoxin B1 (16-130 μg/kg). Three assays were run on each of the 32 combinations of feed and levels of aflatoxin. Mean recoveries were 85.9-92.8% at levels of 16.5,32.9,65.8, and 131.6 μg/kg. The relative standard deviation per assay was 18.6%. This method is more rapid and less involved than most previously published methods for mixed feeds.
Derivation of Fluorometric Chlorophyll and Pheophytin Equations
Authors: Kollig Heinz P 
Published: February 2020

Abstract
Equations for calculation of chlorophyll a and pheophytin a by fluorometry have been cited in a number of publications. None of them, however, includes the derivation of the equations to substantiate their validity. The derivation is given here to let the user apply the equations with confidence.
High Pressure Liquid Chromatographic Determination of Carbadox and Pyrantel Tartrate in Swine Feed and Supplements
Authors: Lowie Dwight M , Teague Robert T , Quick Floyd E , Foster Clarence L 
Published: February 2020

Abstract
A rapid yet reliable procedure for the simultaneous extraction and assay of carbadox and pyrantel tartrate is described. The feed is extracted with water-acetonitrile-methanol and cleaned up on a short alumina column. The eluant is separated by high pressure liquid chromatography and the compounds are detected at different wavelengths. The drugs of interest are well resolved in all feeds studied. The procedure has also been applied to a wide range of feeds which contained either one of the drugs or both in combination. No significant interferences were observed. Spiked sample recoveries were 97% for carbadox and 101% for pyrantel tartrate. Ruggedness test coefficients of variation were 2.0% for carbadox and 2.1% for pyrantel tartrate.
Microbiological Assay for Antibiotics in Surface Waters
Authors: Katz Jack M , Katz Stanley E 
Published: February 2020

Abstract
Assay procedures were developed for determining bacitracin, chlortetracycline, erythromycin, oxytetracycline, penicillin, streptomycin, and tylosin residues in surface waters. Direct addition of solid potassium phosphate buffering salts to water samples enabled suitable pH adjustments for optimum assay conditions. Recoveries from 2 surface waters averaged 97.9 and 102.7% for chlortetracycline, 101.0 and 101.5% for bacitracin, 94.5 and 95.3% for erythromycin, 84.2 and 89.8% for oxy tetracycline, 82.3 and 97.5% for penicillin, 97.4 and 99.2% for streptomycin, 87.4 and 94.2% for tylosin.
Determination of Xanthates, Dithiocarbamates, and Some Fungicides by Titration with Electrogenerated Iodine in Anhydrous Acetonitrile
Authors: Clyde Dale D 
Published: February 2020

Abstract
Xanthates, dithiocarbamates, and the fungicides maneb and zineb were determined by titration with electrogenerated iodine in anhydrous acetonitrile. The electrolyte was potassium iodide. The generating electrode was a platinum spiral (2.5 cm diameter, 2 mm cross section). The enclosed cell compartment was continuously flushed with dry nitrogen, and sample solutions (0.20-0.40 mL) were introduced by syringe. With the aid of 2 platinum electrodes, the end point was indicated amperometrically. Ten minutes was required for each determination. The compounds were determined at ≥5 μequiv. with relative errors of 0.21-9%. Precision is 0.60-5.7%. Thiourea, sulfur, and urea did not interfere, but thioacetamide did. Solutions of maneb and zineb in dimethyl sulfoxide are stable enough that μequiv. amounts of each compound can be determined with a relative error of 7% or less.
Determination of Trif luralin, Diallate, Triallate, Atrazine, Barban, Diclofop-Methyl, and Benzoylprop-Ethyl in Natural Waters at Parts per Trillion Levels
Authors: Lee Hing-Biu , Chau Alfred S Y 
Published: February 2020

Abstract
A sensitive multiresidue method is presented for the determination of 7 neutral herbicides in natural waters, with practical detection limits between 5 and 100 ng/L(ppt). The extraction was carried out at pH ≼1, using dichloromethane, so that acid-type herbicides can also be incorporated in the future. The entire cleanup procedure involves base partitioning, preliminary cleanup and fractionation on a 10% deactivated Florisil column, and final cleanup of the fractions on an activated Florisil column. However, the cleanup procedure is flexible enough to permit the analyst to use some or all of the cleanup steps, depending on the herbicide levels of interest. Recoveries of the 7 herbicides from distilled and natural water samples were between 82 and 104% at 2 fortification levels. Furthermore, this basic analytical scheme has been demonstrated, separately, to be effective in the determination of other neutral compounds such as PCBs, 18 organochlorine pesticides, and chlorobenzenes and thus has a potential to be developed into a multiclass, multiresidue method.
Determination of 2-Chloroethanol in Honey, Beeswax, and Pollen
Authors: Bruns Gary W , Currie Robert A 
Published: February 2020

Abstract
Procedures were developed and tested for the determination of residues of 2-chloroethanol (ethylene chlorohydrin, ECH) in honey, beeswax, and pollen. Recoveries of ECH from fortified samples averaged 91,87, and 89%, respectively, for each substrate. The maximum amount of ECH found in substrate fumigated with ethylene oxide was 36 μg/g in honey, 124 μg/g in beeswax, and 132 μg/g in pollen. A tendency was noted for darker waxes, which contain larger amounts of naturally occurring chlorides than light-colored waxes, to contain the greater amounts of ECH. A gas-liquid chromatograph equipped with a Dohrmann halogen-specific detector was used for identification and quantitation.
Analysis of Fat-Soluble Vitamins. XXVIII. High Performance Liquid Chromatographic Determination of Vitamin D in Pet Foods and Feeds: Collaborative Study
Authors: Vries Ellen J De , Bemmel Pieter Van , Borsje Ben ,   Collaborators:, Adams M L , Baillies T , Berthels J , Rosario C M del , Egtberts W , Gillingham P J , Giuliany B , Hancock W , Haustraete K , Herforth S , Hsieh B , Jensen E Klint , Knapstein H , Mahn F P , Nabholz A , Nedelkovitch G , Nicolas E C , Nicolaux G , Oelrich E , Phillips G F , Phlix J , Richter E F , Schwarze P , Smallidge R L , Steuerle H , Thiele U , Tichelaar G R , Venteicher R , Westergaard S , Woo W O , Zygmunt L 
Published: February 2020

Abstract
A high performance liquid chromatographic (HPLC) method for vitamin D in pet foods and feeds at low concentrations (2-8 IU/g = 50-200 ppb) was studied collaboratively. The procedure consists of the following purification steps: saponification, extraction oMhe unsaponifiable fraction, chromatography on alumina, cleanup on reverse phase HPLC, and quantitation with straight phase HPLC. The original method, developed by Knapstein, was simplified by deleting the quantitative TLC step. Six coded samples were distributed to 31 laboratories, along with a known sample containing 15 IU/g to allow practice of the rather complicated procedure. Eighteen collaborators returned their results. Results for the spiked samples show good recovery. The estimates of repeatability and reproducibility are 0.96 and 2.2 IU/g for spiked samples and 1.5 and 3.1 IU/g for commercial samples, respectively, which are considered acceptable for these low concentrations. The method has been adopted official first action.