bluuebunny/crossref_metadata_2025_split huggingface dataset:
Minicolumn Detection Methods for Aflatoxin in Yellow Corn: Collaborative Study
Authors: Shannon Gail M , Shotwell Odette L 
Published: February 2020

Abstract
The CPC modified method, the Holaday modified method, and the combination of the 2 procedures have been compared. The CPC modified method involves more cleanup steps but has a more sensitive column. The Holaday modified procedure has fewer cleanup steps, but the column is more difficult to interpret. The combination CPC-Holaday, which has proven to be the most satisfactory, combines the speed and simplicity of the Holaday extraction and the sensitivity of the Velasco minicolumn used in the CPC method. Levels of 10 ng/g were detected by 89% of the collaborating laboratories using the combination, Holaday-Velasco, method. The combination method has been adopted as official first action.
Production of Aflatoxin in Cocoa Beans
Authors: Lenovich Lawrence M , Hurst W Jeffrey 
Published: February 2020

Abstract
Aflatoxin was produced in both non-autoclaved and autoclaved Ivory Coast cocoa beans inoculated with Aspergillus parasiticus NRRL 2999 under optimum laboratory growth conditions. Total aflatoxin levels ranged from 213 to 5597 ng/g substrate. Aflatoxin was quantitated by using high pressure liquid chromatography (HPLC). Raw, non-autoclaved cocoa beans, also inoculated with aspergilli, produced 6359 ng aflatoxin/g substrate. Variation in aflatoxin production between bean varieties was observed. Total aflatoxin levels of 10,446 and 23,076 ng/g substrate were obtained on Ivory Coast beans inoculated with A. parasiticus NRRL 2999 and NRRL 3240, respectively. Aflatoxin production on Trinidad and Malaysian beans was 28 and 65 ng aflatoxin/g substrate. These data support previously reported low level natural aflatoxin contamination in cocoa.
Computerized Gas-Liquid Chromatographic Method for Content Uniformity Analysis of Dicyclomine Hydrochloride Capsules and Tablets
Authors: Brownell Charles R , Alber Larry L 
Published: February 2020

Abstract
An automated, computerized method is presented for the content uniformity determination of dicyclomine hydrochloride capsules and tablets, using up to 4 automatic sampler-equipped gas chromatographs interfaced with a minicomputer. A 3% OV-17 column is used with anthracene as an internal standard. Five sample injections are bracketed by standard mixtures containing about 90 and 110% of the labeled dicyclomine hydrochloride. Data are taken on-line simultaneously from each gas chromatograph and a computergenerated report is produced. Calculations use a BASIC program with linear fit of the 90 and 110% standard mixture. Individual tablet or capsule results are printed in milligrams and per cent declared, including summary calculations of average, high, low, standard deviation, and coefficient of variation. The GLC results are comparable (within 1%) to those obtained using the USP procedure.
Extrusion of Homogeneous Pastes from Small Samples of Dried Fruit
Authors: Neumann Harry J 
Published: February 2020

Abstract
A simple, rapid procedure is described for preparing homogeneous pastes from small quantities of dried fruit or similar soft, pasty material. Raisin pastes prepared from five 60 g samples by extrusion through a plate with 0.046 in. diam holes, and by the AOAC grinding procedure were in close agreement in average moisture content and standard deviation. The amount of sample lost in the equipment was much less by extrusion than by grinding with a food chopper, averaging 1.3 and 32.4 g, respectively. Various dried fruits including apples, apricots, figs, pears, prunes, raisins, and a glacéed fruit mix, with moisture contents of 12.6-33.9%, were extruded as pastes through either 1 plate with 0.046 in. diam holes, or a stack of 3 plates with 0.045, 0.046, and 0.033 in. diam holes, except that figs pressed with 3 plates were compacted. Moisture data from averages of three 25 g samples were equally precise using 3 plates or 1 plate.
Evaluation of 14 Charcoal-Polyurethane Foam Mixtures for the Separation of Mirex and Photomirex from Aroclor 1254
Authors: Babjak Ludwig J , Chau Alfred S Y 
Published: February 2020

Abstract
The efficiency of 14 different types of charcoals mixed with polyurethane foam (40% charcoal/60% foam, w/v) for the separation of photomirex and Mirex from Aroclor 1254 was investigated. Photomirex and Mirex were eluted with 10 mL cyclohexane from minicolumns containing 0.2 g charcoal- foam mixture. An additional elution with 10 mL benzene yielded Aroclor 1254. Average recovery using Norit C-170 charcoal-foam mixture was 99.1% for photomirex at the 1.0 μg level, 100.1% for Mirex at the 1.0 μg level, and 96.8% for Aroclor 1254 at the 3.0 μg level. For the other 13 charcoals investigated, recoveries from duplicate analyses were 47.0-115.5% for photomirex, 71.9-106.1% for Mirex, and 23.3-114.6% for Aroclor 1254.
Comparison of Two Extraction Procedures for Recovering Nitrite from Cured Meat Products
Authors: Sen Nrisinha P , Lee Young C , Mcpherson Marcia 
Published: February 2020

Abstract
A study was undertaken to determine the extent of loss of nitrite during the analytical workup of cured meats for nitrite analysis. Two extraction techniques were compared: (A) a relatively long (2 hr) and hot (80°C) procedure carried out at the natural pH of the sample, and (B) the method of Sen and Donaldson that specifies an alkaline solution and much milder conditions (20 min at 50°C at pH 8) for extraction. The data obtained suggest that considerable losses of nitrite can occur with the former procedure, especially in acidic samples. The overall percentage recoveries of added nitrite by the 2 methods ranged between 20 and 112, and 80 and 114, respectively. Average percentage recoveries for the acidic (pH &lt;5) samples only were 47.2 for Method A as compared with 100.2 for Method B.
Gas Chromatographic-Mass Spectrometric Analysis, Identification, and Detection of Adulteration of Lavender, Lavandin, and Spike Lavender Oils
Authors: Prager Manfred J , Miskiewicz Michael A 
Published: February 2020

Abstract
A gas chromatographic procedure was developed to distinguish lavender, lavandin, and spike lavender oils. Quantitative determination showed that each oil contained about a dozen components present to the extent of 1% or more. These compounds were generally common to the 3 oils. The concentrations of these components fell into characteristic ranges by which the 3 oils could be identified and adulterations could be detected. Samples were identified primarily on the basis of concentrations of limonene, 1,8-cineole, cis-β-ocimene, camphor, linalyl acetate, β-caryophyIlene plus terpineol-4, and borneol.
High Pressure Liquid Chromatographic Determination of the Rodenticide Brodifacoum in Rat Tissue
Authors: Koubek Kenneth G , Ussary James P , Haulsee Ronald E 
Published: February 2020

Abstract
An HPLC method was developed to determine residues of individual isomers of brodifacoum (3-[3-4'-bromo[1,1'-biphenyl]-4-yl)-1, 2, 3, 4-tetrahydro- 1 -naphthalenyl]- 4 -hydroxy-2H- 1 -benzopyran-2-one) in rat tissue. The compound was extracted twice with 10% methanol in chloroform, filtered, and cleaned up by using automated gel permeation chromatography. A final cleanup on a silica gel SEP-PAK was added to protect the analytical column from irreversible adsorption and to reduce analysis time. The analysis was done on a μPorasil column; a UV detector was used for quantitation. Recoveries of brodifacoum added to rat tissue in concentrations of 0.12-5.0 ppm were greater than 90%.
Gas-Liquid Chromatographic Determination of Permethrin in Bovine Tissues
Authors: Oehler Delbert D 
Published: February 2020

Abstract
A method is presented for the determination of permethrin (m-phenoxybenzyl cis,trans-(±)-3-(2,2-dichlorovinyl) - 2,2 - dimethylcyclopropanecarboxylate) in bovine tissues. Fat and muscle samples were cleaned up first by liquid-liquid partition on a bonded phase chromatographic column. Final cleanup of fat and muscle was performed on a short Florisil column. Liver, kidney, spleen, and heart tissues only required cleanup on a Florisil column before quantitation of permethrin by electron capture gas-liquid chromatography.
Quantitative Determination of Tris-(2,3,-dibromopropyl) Phosphate by Densitometry of Thin Layer Chromatograms
Authors: Gardner Albert M 
Published: February 2020

Abstract
The flame retardant tris-(2,3-dibromopropyl) phosphate (Tris) was chromatographed on silica gel thin layer plates, using ethyl acetate-hexane (30+70) as the developing solvent. Tris was visualized by spraying the chromatogram with 1% aqueous silver nitrate followed by exposure to ultraviolet light for 40 min. Tris appeared as dark gray spots on a white background; the spots were quantitated by densitometry at 600 nm. The lower level of sensitivity was 50 ng; calibration plots were linear from 50 to 800 ng. The procedure was developed to determine the levels of unmetabolized Tris remaining after exposure to sewage sludge suspensions. Recovery of Tris from 3 sewage sludge samples fortified at the 1.0 ppm level averaged 97%.
Sampling and Preparation of Samples of Peanut Butter for Aflatoxin Analysis
Authors: Waltking Arthur E 
Published: February 2020

Abstract
Procedures are discussed for sampling peanut butter and preparing those samples for aflatoxin analysis. Special emphasis is placed on sampling the product from shipping pallets and comminuting chunk style peanut butter in order to reduce the variability in the analysis associated with the nonuniform distribution of aflatoxin in the product. The slurry method of preparation is a convenient means of obtaining a sample which is representative of a nonhomogeneous product.
Confirmatory Test for the High Pressure Liquid Chromatographic Determination of Aflatoxin B1
Authors: Davis Norman D , Diener Urban L 
Published: February 2020

Abstract
The iodine derivative of aflatoxin B1 was determined by reverse phase high pressure liquid chromatography with fluorescence detection. Aqueous solutions of aflatoxin B1 were chromatographed on a Bondapak C18 column with methanol–water before and after treatment with iodine. A 4.5-min shift in retention time and a 25-fold increase in fluorescence resulted from the reaction.
Gas-Liquid Chromatographic Determination of Chlorinated Benzenes and Phenols in Selected Biological Matrices
Authors: Lamparski Lester L , Langhorst Marsha L , Nestrick Terry J , Cutié Sergio 
Published: February 2020

Abstract
The determination of higher chlorinated benzenes and chlorinated phenols at parts per billion or parts per million levels in biological samples is described. The method includes sulfuric acid digestion, silica gel column chromatography, methylation, alumina column chromatography, and detection by electron capture gas chromatography. Recoveries are reported (or fish flesh, rabbit tissues, and duck tissues with detection limits of 10-15 ppb (ng/g tissue).
Argon Plasma Emission Spectrometry of Boron in Fertilizers: Comparison with Spectrometric and Distillation Procedures
Authors: Woodis Terry C , Hunter G Bradley , Holmes John H , Johnson Frank J 
Published: February 2020

Abstract
A much faster and equally accurate method is described for determining boron in fertilizers by argon plasma emission spectrometry at 249.67nm. Results by the method are compared with results from a methyl borate distillation method and a modified azo-methine H spectrometric procedure. No significant differences in results were found among the methods studied.
High Pressure Liquid Chromatographic Determination of Antihistamine-Adrenergic Combination Products
Authors: Bachman William J 
Published: February 2020

Abstract
Reverse phase high pressure liquid chromatography (HPLC) with ion-pairing is used for the determination of pseudoephedrine hydrochloride in combination with triprolidine hydrochloride or chlorpheniramine maleate in sirups and tablets. Sirups require a preliminary column chromatography cleanup step. Response is linear for pseudoephedrine hydrochloride (range of 0–20 μg), chlorpheniramine maleate (range of 0–1.3 μg), and triprolidine hydrochloride (range of 0–1.0 μg). Recoveries from synthetic formulations were 98.8–101.3% for pseudoephedrine hydrochloride, 100.0–101.2% for chlorpheniramine maleate, and 97.7–99.8% for triprolidine hydrochloride. The coefficient of variation for the method is less than 1%.
Protocols for Surveys, Sampling, Post-Collection Handling, and Analysis of Grain Samples Involved in Mycotoxin Problems
Authors: Davis Norman D , Dickens J William , Freie Robert L , Hamilton Pat B , Shotwell Odette L , Wyllie Thomas D , Fulkerson J F 
Published: February 2020

Abstract
This report examines and summarizes current knowledge regarding mycotoxin surveys, sampling techniques, conditions conducive to post-collection production of mycotoxins in grain samples, and analytical methods for mycotoxin analysis. Priority attention is given to samples of corn suspected of containing aflatoxin. The report includes recommendations where deemed appropriate by the Ad Hoc Work Group
Spectrophotometric Determination of Carbofuran Residues in Water
Authors: Handa Swadesh K 
Published: February 2020

Abstract
A spectrophotometric method has been developed for the microdetermination of carbofuran in water. The method is based on the reaction of carbofuran phenol (2,3-dihydro-2,2-dimethyI-7-hydroxy benzofuran) with nitric acid to form a colored compound with an absorption maximum at 345 nm. The method is applicable to residues in the range 10-150 μg/5 mL solution.
Gas-Liquid Chromatographic Determination of Melengestrol Acetate in Cattle Feed Supplements: Collaborative Study
Authors: Davis Raymond A , Kratzer D Dal , Geng Shu ,   Collaborators:, Barney S L , Jeffus M T , Karnemaat J N , Pollack R , Sics U , Zietlow D C 
Published: February 2020

Abstract
The assay for melengestrol acetate (MGA) in cattle feed supplements was the subject of a collaborative study using 6 laboratories. Two feed formulations were each fortified with 0, 0.0625, 0.125, 0.500, 1.00, and 1.50 mg MGA/lb of supplement, and each laboratory assayed 4 samples of each level of each formulation by electron capture gas chromatography after liquid-liquid extraction of each sample followed by solvent partition and column chromatography cleanup procedures. Overall recovery was 83.2% with a pooled within-laboratory sample-to-sample standard deviation of 9.5%. This includes the variability due to formulation, batches, days, levels of MGA, samples, and their interactions. Including the collaborators as a source of variance results in an overall standard deviation of 15.0%. The major sources of variability were associated with collaborator, formulation, and level of MGA. Lower than expected recoveries were attributed to difficulty in recovering MGA from samples containing concentrations of MGA below the range of the method and the inadvertent substitution by some laboratories of ethanol-free chloroform for the ethanol-containing reagent grade chloroform specified in the methodology. On the basis of the collaborative results, the method has been adopted as official first action for MGA in cattle feed supplements at concentrations from 0.125 to 1.00 mg MGA/lb.
High Performance Liquid Chromatographic Determination of Fructose, Glucose, and Sucrose in Molasses
Authors: Damon Carolyn E , Pettitt Bruce C 
Published: February 2020

Abstract
Fructose, glucose, and sucrose were determined quantitatively in molasses by high performance liquid chromatography (HPLC) using maltose as an internal standard. After a simple cleanup procedure, chromatographic separation required less than 20 min for the 17 molasses samples. HPLC gave lower results for reducing sugars (fructose plus glucose) and for sucrose by an average of 3.9 and 1.2%, respectively, when compared to results obtained by classical methods. The lower values are believed to result from elimination of interfering substances by this method. The values probably reflect more accurately the true composition of the molasses. Repetitive injections of a standard solution indicated a coefficient of variation of 2.0% for fructose and glucose and of 2.2% for sucrose.
Solvent Extraction and Flameless Atomic Absorption Determination of Arsenic in Biological Materials
Authors: Thiex Nancy 
Published: February 2020

Abstract
This method for the determination of arsenic specifies wet digestion of biological materials, followed by reduction of arsenic(V) to arsenic(III) and extraction of arsenic(III) with diethylammonium diethyldithiocarbamate (DDDC) in chloroform. The extract is analyzed by flameless atomic absorption spectrometry (AAS). Recoveries of arsenic from plant and animal tissues ranged from 88 to 108%, averaging 99%. Analyses of rat tissues, using a radioisotope technique, averaged 103% of theoretical. Repeatability studies on rat tissues showed the method to be consistent with coefficients of variation ranging from 3.0 to 8.5%, and a test for ruggedness showed that the method is not affected by slight variations in procedure, but is affected by the presence of Fe and Cu. The method is sensitive to about 0.04 μg arsenic in the total digest (injections of 20 μl of a 4 ng/mL solution).
Preliminary Comparison of Methods for Determining Sodium in Fertilizers
Authors: Corominas Luis F , Boy Victor M , Guijosa Manuel 
Published: February 2020

Abstract
The AOAC official first action method 2.147–2.150 for the flame emission spectrophotometric (FES) determination of sodium in fertilizers was compared with the atomic absorption spectrophotometric (AAS) method and the sodium selective electrode (SSE) method. Two synthetic NPK samples, 3 commercial samples (urea, DAP, and superphosphate), 2 Magruder NPK check samples, and one Magruder muriate check sample were used for the study. Statistically significant differences were obtained in both averages and standard deviations for all samples. In general, the precision for all methods was acceptable; the AAS method seems to be the more accurate; the AOAC method needs to be revised; and the SSE method has the tendency to give higher values. Additional experimental work is necessary to define which method is the most convenient.
Enumeration and Confirmation of Bacillus cereus in Foods: Collaborative Study
Authors: Lancette Gayle A , Harmon Stanley M ,   Collaborators:, Brooks D , Bryant R , Chiu J , Graham J , Guilfoyle D , Hill W , Latt T , Noah C , Placencia A , Pratt M , Radle D , Smith A , Solomon H , Staben D , Stern N , Thaker N 
Published: February 2020

Abstract
A collaborative study was conducted in 15 laboratories to evaluate 2 different techniques for enumerating Bacillus cereus in foods. A direct plating technique using mannitol-egg yolk-polymyxin agar and a most probable number (MPN) technique using trypticase-soy-polymyxin broth were compared for the enumeration of high and low populations of B. cereus in mashed potatoes. The collaborative results showed that the overall mean recovery obtained with the low population level was essentially the same by both techniques. However, the overall mean recovery was significantly higher by the direct plating technique at the high population level. A statistical evaluation of the data also showed that the direct plating technique had better repeatability and reproducibility than did the MFN technique at both the high and low population levels. These results suggest that the MPN technique is suitable for examining foods containing low populations of B. cereus, but that the direct plating technique is preferable for foods that contain a high population of this organism. The confirmatory technique used in the proposed method is reliable for presumptive identification of isolates as B. cereus. The method has been adopted as official first action.
Freezing Point Measurement of Lactose Hydrolysis in Acid Whey and Lactose Solutions
Authors: Baer Robert J , Frank Joseph F , Loewenstein Morrison 
Published: February 2020

Abstract
A method for determining lactose hydrolysis by freezing point determinations is described. There is a direct relationship between freezing point and lactose hydrolysis in neutralized acid whey (r = 0.985) and lactose solutions (r = 0.998). In both the acid whey and the lactose solutions that contained 4.6 to 5.0% lactose, the freezing point was depressed approximately 0.050°H for each 1% lactose hydrolyzed
High Performance Liquid Chromatographic Determination of Carbohydrates in Chocolate: Collaborative Study
Authors: Hurst W Jeffrey , Martin Robert A ,   Collaborators:, Bueno M , Clemente H , DeVries J W , Levi C , Li B , Popovich D J , Sheeley R , Schumacher D , Stewart K , Taylor J , Toomey P 
Published: February 2020

Abstract
A collaborative study determining sucrose, glucose, fructose, maltose, and lactose in chocolate products was conducted using a previously published high performance liquid chromatographic (HPLC) method. Five samples (2 milk chocolates, 1 dark chocolate, 1 powdered mix, and 1 sirup) were analyzed in duplicate by 7 collaborators. The results indicate adequate method precision. In addition, the HPLC method allows for the simultaneous determination of 5 saccharides in chocolate products in 15 min. The method has been adopted as official first action.
Extraction and Cleanup of Soil Arsenical Residues for Analysis by High Pressure Liquid Chromatographic–Graphite Furnace Atomic Absorption
Authors: Iadevaia Rosa , Aharonson Nadav , Woolson Edwin A 
Published: February 2020

Abstract
An analytical procedure for the extraction and cleanup of arsenical residues from soil was developed to meet the specific requirements for separation by high pressure liquid chromatography (HPLC) and on-line analysis by a graphite furnace atomic absorption spectrophotometer (GFAA). Soil samples were extracted with 2M aqueous NH4OH, cleaned on a carbon-Celite chromatographic column, concentrated to 1 g soil extract equivalent per mL, and determined by HPLC-GFAA. Recovery values were as follows: dimethylarsinic acid (cacodylic acid, CA) 90%; methanearsonic acid (MAA) 83%; arsenate 56%; and arsenite 64%. The limit of detection was 0.5 ppm in soil. Additional cleanup on cellulose thin layer chromatographic (TLC) plates improved sensitivity to less than 0.1 ppm and also served for confirmation of identity. The soil extract matrix did not appear to affect GFAA signal response. High salt content in concentrated soil samples altered the dimethylarsinic acid HPLC retention volume. By the time of analysis, arsenite was completely oxidized to arsenate in soil extractant.
Carbon–Foam Chromatographic Separation of Non-o,o´-Chlorine Substituted PCBs from Aroclor Mixtures
Authors: Huckins James N , Stalling David L , Petty Jimmie D 
Published: February 2020

Abstract
Columns of activated carbon dispersed on shredded polyurethane foam were used to separate non-o,o´-chlorine (Cl) substituted polychlorinated biphenyls (PCBs) from mg quantities of Aroclors 1016, 1242, 1248, 1254, and 1260. Aroclor 1248 contained the highest concentration (3400 μg/g) of highly toxic 3,4,3´,4´tetrachlorobiphenyl (TCB). Lesser amounts of 3,4,3’,4’-TCB were also found in Aroclors 1242 and 1254. However, we were unable to detect 3,4,3’,4’-TCB in Aroclors 1016 and 1260. Varying amounts of the non-o,o´-Cl substituted 3,4,4´-trichlorobiphenyl and 3,4,3´,4´,5´-pentachlorobiphenyl were found in most of the Aroclor mixtures. No residues of 3,4,5,3´,4´,5´-hexachlorobiphenyl were detected in the Aroclor mixtures examined. Using carbon-foam chromatography and high resolution capillary gas chromatography, 0.11 μg 3,4,3´,4´-TCB/g was detected in 3 subsamples of a composite of 5 carp from the Ohio River.