bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid, Semimicro Method for Determination of Polycyclic Aromatic Hydrocarbons in Shellfish by Automated Gel Permeation/Liquid Chromatography
Authors: Musial Charles J , Uthe John F 
Published: February 2020

Abstract
A simple, rapid, easily automated method is described for the determination of polycyclic aromatic hydrocarbons (PAHs) in shellfish such as American lobster (Homarus americanus) and blue mussel (Mytilus edulis). PAHs are extracted from small amounts (1-8 g) of tissue by saponification in IN ethanolic potassium hydroxide followed by partitioning into 2,2,4-trimethylpentane. This solution is evaporated just to dryness by rotary evaporation and the residue is dissolved in cyclohexane- dichloromethane (1 + 1) for gel permeation chromatography (GPC) on Bio-Beads SX-3. The GPC procedure is ideal as a screening method in the range 25-18 000 ng PAHs/g tissue. If individual PAH measurements are required, the appropriate GPC fraction is collected and PAHs are separated by reverse phase liquid chromatography (LC) with fiuorometric detection. Individual PAHs at concentrations as low as 0.25-10 ng/g can be determined. Recoveries of added fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[A]fluoranthene, benzo[b]fluoranthene, benzo[α]pyrene, dibenz[a,h]anthracene, benzo[ghi]perylene, and indeno[l,2,3-cd]pyrene were quantitative, with relative standard deviations ranging from 0.0 to 16.9%.
Colorimetric Determination of Alkaline Phosphatase as Indicator of Mammalian Feces in Corn Meal: Collaborative Study
Authors: Gerber Harriet ,   Collaborators:, Beavin B , Brown S , Bryce J , Deblois B , Klein R , Knueppel J , LaRose J , Lmdroth S , Mayers D , McDonnell J , Schneider P , Trauba R 
Published: February 2020

Abstract
In the official method for rodent filth in corn meal, filth and corn meal are separated in organic solvents, and particles are identified by the presence of hair and a mucous coating. The solvents are toxic, poor separation yields low recoveries, and fecal characteristics are rarely present on all fragments, especially on small particles. The official AOAC alkaline phosphatase test for mammalian feces, 44.181-44.184, has therefore been adapted to determine the presence of mammalian feces in corn meal. The enzyme cleaves phosphate radicals from a test indicator/substrate, phenolphthalein diphosphate. As free phenolphthalein accumulates, a pink-to-red color develops in the gelled test agar medium. In a collaborative study conducted to compare the proposed method with the official method for corn meal, 44.049, the proposed method yielded 45.5% higher recoveries than the official method. Repeatability and reproducibility for the official method were roughly .1.8 times more variable than for the proposed method. The method has been adopted official first action.
Production and Isolation of Aflatoxin M1 for Toxicological Studies
Authors: Hsieh Dennis P H , Beltran Linda M , Fukayama Mark Y , Rice David W , Wong Jeffrey J 
Published: February 2020

Abstract
One hundred mg aflatoxin Mi was produced and purified for toxicological studies. Aspergillus flams NRRL 3251 was cultured on rice to produce aflatoxins B1, B2, M1, and M2. B1 and B2 were separated from M1 and M2 by a normal phase low pressure liquid chromatography (LC) column. M1 was then separated from M2 by a reverse phase low pressure LC column. Recoveries of aflatoxins from the LC columns were about 90%. The purified M1 was confirmed by ultraviolet-visible spectrometry, mass spectrometry, nuclear magnetic resonance spectrometry, optical rotation, and its mutagenicity to Salmonella typhimurium TA98.
Liquid Chromatographic Determination of Chlorpropamide in Tablet Dosage Forms: Collaborative Study
Authors: Everett Richard L ,   Collaborators:, Aranda E , Colon M , Illuminati J , Kelley N , Roberts S , Shostak D 
Published: February 2020

Abstract
A reverse-phase liquid chromatographic method was developed for determining chlorpropamide in tablet dosage forms. Linearity was established over the range 0.2-2.0 μg at a wavelength of 240 nm. The Associate Referee obtained a mean recovery for a synthetic tablet mixture of 99.2%, with a relative standard deviation (RSD) of 1.41. For an authentic tablet mixture, collaborators obtained a mean recovery of 99.6% with an RSD of 0.60%. RSDs were 1.24% for 250 mg/tablet commercial product and also for 100 mg/tablet commercial product. The method has been adopted official first action.
Headspace Gas Chromatographic Method for Determination of Ethanol in Canned Salmon: Collaborative Study
Authors: Hollingworth Thomas A , Throm Harold R , Wekell Marleen M , Trager William F , O’Donnell Michael W ,   Collaborators:, Hons F , Lerke P , Mowdy D , Saxton W , Wiggin K , Wood J 
Published: February 2020

Abstract
Six laboratories collaboratively studied a headspace gas chromatographic method for determination of ethanol in the aqueous phase of canned salmon. Ethanol is determined by a headspace sampling technique with tert-butanol as the internal standard, using a gas chromatograph equipped with a Super Q column and a flame ionization detector. With outliers excluded, the mean recoveries from samples spiked with 25.1 and 78.4 ppm ethanol were 112 and 110%, respectively. For the 4 sample pairs quantitated, repeatability coefficients of variation ranged from 1.42 to 4.25% and reproducibility coefficients of variation from 2.55 to 8.09%, with 3 of the 4 reported values less than 5%. The method has been adopted official first action.
Gas Chromatographic Profile Analysis of Basic Nitrogen-Containing Aromatic Compounds (Azaarenes) in High Protein Foods
Authors: Grimmer Gernot , Naujack Klaus-Werner 
Published: February 2020

Abstract
A method is described for the determination of basic nitrogen-containing polycyclic aromatic compounds (N-PACs, azaarenes) in meat. The enrichment procedure includes liquid-liquid partition (dimethylformamide-water-cyclohexane), extraction of N-PACs by sulfuric acid, reextraction after neutralization by cyclohexane or, alternatively, by nonadsorbing ion exchange chromatography. Further purification is performed by column chromatography on Sephadex LH20 using a dosed system to avoid sample contamination by laboratory pollutants. N-PACs are analyzed by capillary gas chromatography and measured by comparing to the corresponding peak areas of an internal standard (e.g., lO-azabenzo(a)pyrene). The limit of detection of this method ranges from 0.1 to 0.4 ng for benzacridines, dibenzacridines, and their methyl derivatives. The results of a collaborative study, stimulated by IUPAC, are reported: Coefficients of variation for the various azaarenes were 4.0-13.6% for the check analysis and 10.4-25.4% for a spiked ham sample. Consequently, IUPAC suggests this procedure as a recommended method.
Variability of Mouse Bioassay for Determination of Paralytic Shellfish Poisoning Toxins
Authors: Park Douglas L , Adams Willard N , Graham Stuart L , Jackson Randolph C 
Published: February 2020

Abstract
Toxic shellfish extracts and paralytic shellfish poison (PSP) standard solutions, tested over a range of pH levels, storage conditions, and temperatures, were monitored for toxin concentration, using the mouse bioassay and thin layer chromatography (TLC). A comparison of PSP toxin concentrations in toxic shellfish extracts and PSP standard solutions when dilution was varied suggests that other factors in the shellfish extracts contribute to the toxicity in mice; the closest agreement was at the death time range of 5-8 min. The toxicities of PSP standard solutions at pH levels ranging from 2 to 6 and held at 4°C for various times were relatively constant; however, there was a gradual decrease in toxicity with pH 6 solutions. Also, standard solutions (pH 6) held at 4°C for 28 days showed a 50% decrease in toxicity when the pH was adjusted to 2. TLC analyses of PSP standard solutions and toxic shellfish extracts revealed multiple spots at the Rf ranges of saxitoxin/neosaxitoxin and gonyaulax toxins I-IV. PSP standard solutions usually had a single spot in the saxitoxin/neosaxitoxin area. No attempt was made to confirm the identity of these compounds. Previously tested toxic shellfish extracts with subsequent pH adjustment to 1.5 and additional heat treatment (100°C for 5 min) showed no appreciable difference in mouse toxicity. The use of antifoaming agents during the acid extraction step did not affect the final amounts of PSP obtained
Gas Chromatographic Determination of the Plant Growth Regulator Flurprimidol in Soil and Soil-Grass Samples
Authors: West Sheldon D , Rutherford Bonnie S 
Published: February 2020

Abstract
A method is described for the determination of flurprimidol residues in soil and soil-grass samples. Flurprimidol is extracted from the sample by refluxing with methanol-water. An aliquot is partitioned into hexane and purified by alumina B Sep-Pak column chromatography. The compound is detected and measured by gas chromatography with electron capture detection. Residue identity is confirmed by gas chromatography-mass spectrometry with detection at m/z 269.0. The detection limit is 0.01 ppm, and recoveries for control samples fortified with flurprimidol at 0.01-2.0 ppm averaged 80% for soil and 78% for soil-grass samples.
Identification of cis- and trans-1,1,2,3,4-PentachIoro-4-[1-methylethoxy]-l,3-butadiene Residues in Mississippi River Fish
Authors: Yurawecz Martin P , Chen Jo-Yun T , Puma Bartholomew J 
Published: February 2020

Abstract
The cis- and trans-isomers of 1,1,2,3,4-pentachloro-4-[1-methylethoxy]-1,3-butadiene have been identified as contaminants in fish caught from the Mississippi River at St. Louis, MO, and as far as 150 miles south of that location. Up to 0.1 ppm of the cis-isomer and 0.8 ppm of the trans-isomer were determined by using a method based on the AOAC multiresidue method for detecting organochlorine and organophosphorus pesticides. In tests of the modified AOAC method on spiked fish, both isomers were quantitatively recovered (95-106%). A mixture of the cis- and trans-isomers was synthesized by reacting hexachlorobutadiene with sodium isopropoxide. Separation of the reaction products by Florisil column chromatography provided reference standards of the individual isomers for identification and quantitation of the residues. The stereospecificity of the synthesis reaction and the infrared and mass spectral data used to verify the structures of the products are discussed.
New Liquid Membrane Electrode for Determination of Lidocaine in Local Anesthetic Formulations
Authors: Hassan Saad S M , Ahmed Mona A 
Published: February 2020

Abstract
A new lidocaine-responsive liquid membrane electrode based on the use of the lidocaine reineckate ion pair complex in nitrobenzene solvent has been developed. The electrode displays a linear response for 10-2-10-5M lidocaine over the pH range of 3-6.5. The response time varies from 35 s to 1 min depending on the lidocaine concentration. The life span of the electrode is at least 1 month. Excipients and diluents commonly used in local anesthetic formulations do not interfere. Determination of lidocaine in some pharmaceutical preparations gives results with an average recovery of 99% of the nominal values and a mean standard deviation of 1.7% which compare favorably with those obtained by the U.S. Pharmacopeia method.
Gas Chromatographic Determination of Propachlor in Pesticide Formulations: Collaborative Study
Authors: Tomkins David F ,   Collaborators:, Caparoon W C , Galoux I M , Gentry G M , Hodgins W E , Koenig D K , Law M W , Lee B , Liu J , McAfee S E , Spencer D A , Speth R M , Torma L 
Published: February 2020

Abstract
An isothermal gas chromatographic (GC) method for measuring propachlor in formulations was tested by 12 collaborators. Samples are prepared in acetone and determined using a GC column of 10% SP-2250 on 100-200 mesh Supelcoport, and diisobutyl phthalate as internal standard. Collaborators made single determinations on each of 2 similar materials (matched pairs) on 2 days for 3 pairs of samples. The study generated 62 matched pairs which were used in Youden’s matched pair calculations. The coefficients of variation (CV,) for flowable formulations were 0.84 and 1.48%; the CV, for the granular formulation was 1.28%. The method was simple to use and did not reveal any interferences in the samples tested. The method has been adopted official first action as an AOAC-CIPAC method.
Problems of Official Methods and New Techniques for Analysis of Foods and Feeds for Vitamin A
Authors: Thompson James Neville 
Published: February 2020

Abstract
The official methods for measuring vitamin A and carotene in foods and feeds have evolved over several decades. New procedures are needed to permit the use of modern analytical techniques such as liquid chromatography (LC), and to expand the application of official methods to a wide variety of foods. Recent improvements in methodology are reviewed. Emphasis is often placed on the separations achieved by LC, but all factors that affect quantitation, such as sampling, preparation of standards, and protection of the vitamin against oxidation, must be considered in the development of new methods. Many approaches to analysis are possible because of the versatility of LC but not all of them can be used in official methods. Methods for milk, margarine, and feeds can be prepared now for collaborative assays. Although straightforward methods can be developed for the measurement of βcarotene in certain foods, a full examination of provitamins will probably continue to require a flexible approach and special expertise.
How to Produce a Research Report With Ease and Elegance (or How to Publish and Not Perish in the Process)
Authors: Schick Renee 
Published: February 2020

Abstract
Microcomputers can be used by scientists to search online bibliographic sources and to integrate the references into a research report. Commercial programs, such as Sci-Mate, are available to aid in the search of online databases, and the storage of retrieved references and abstracts.
Data Transmission Through the Telephone Network: Protocols, Pitfalls, and Some Examples
Authors: Venable Richard M 
Published: February 2020

Abstract
Invariably, the situation arises where it is desirable to transfer data from one computer to another, especially from small laboratory systems, word processors, or home computers to large mainframe computers. In many of these cases, there are no common storage media; home computers do not have 9-track tape drives and large mainframes do not have 5¼ in. floppy disk drives. Transmission of data through the telephone network is a viable method for data transfer, which is paradoxically both easier than many believe and more difficult than some may claim. One of the keys to successful data transmission is an understanding of telecommunications protocols, i.e., the rules governing intersystem communication through the telephone network. Some of the most common protocols allow exchanging ASCII-coded data at either 300 or 1200 baud. A variety of computer systems can be used, including IBM and DEC mainframes, a Wang word processor, an IBM PC-compatible microcomputer, and the Atari 800 microcomputer. A specific example is the use of the Atari 800 as an APL terminal, complete with the custom character set, standard ASCII text, and data transfer.
Electron Impact Mass Spectroscopy for Identification of Phencyclidine
Authors: Clark Charles C 
Published: February 2020

Abstract
The electron impact mass spectrum of phencyclidine (PCP) was studied using both deuterium-labeled analogs and high-resolution mass spectroscopy. The deuterium-labeled compounds used were d5.PCP having 5 deuterium atoms on the phenyl ring, d10.PCP having 10 deuterium atoms on the cyclohexyl ring, and d15.PCP having deuterium atoms on both the phenyl and cyclohexyl rings. The identities of some major fragments and some possible pathways for their formation are shown. Electron impact mass spectroscopy is shown to be a definitive test for the identification of PCP.
Accuracy of Gercock™ Milkfat Test Bottles: Collaborative Study
Authors: Bradley Robert L ,   Collaborators:, Albright G , Alioto P , Deaver J , Fleming R , Riesterer B , Stukenberg D , Thompson W , Treleven J , Ward S 
Published: February 2020

Abstract
No novel approaches to improving the accuracy of the Babcock test glassware for milkfat determination have appeared in years. Recent development of a test bottle wherein the calibrated neck of a Gerber bottle was attached to the bulb of a Babcock bottle showed promise. When the normal calibrated portion of the neck was changed from 8% to 5%, accuracy was further improved. Divisions between each percentage mark allowed 2× the accuracy in reading. Eight qualified testing laboratories collaboratively studied both 8% and 5% Gercock milkfat test bottles, using the AOAC method 16.065. Results were similar to those obtained by the Mojonnier method. Standard deviations were smaller among laboratories when the 5 % Gercock test bottle was used. Use of the 5% Gercock bottle has been adopted official first action as an addition in 16.065.
Distillation Method for Determination of Moisture in Spices: Collaborative Study
Authors: Sanna Louis A ,   Collaborators:, Bennett R , Bruce W , Edwards F , Guarino P , Ikeda T , Loney E , Monaco D , Pasek R , Rosner L , Sica S , Sloane R , Williams T , Woodbury J 
Published: February 2020

Abstract
AOAC method 30.005 for determination of moisture in spices by distillation was collaboratively studied to revalidate its reliability. Using toluene as the solvent system, repeatability and reproducibility were acceptable for basil. Using hexane as the solvent for red pepper produced less satisfactory results. The method has been adopted official first action.
Gas Chromatographic Method for Ethylene Dibromide in Grains and Grain-Based Products: Collaborative Study
Authors: Sawyer Leon D , Walters Stephen M ,   Collaborators:, DeCocco F , DePalma R , Ferm R L , Grieb J , Henderson L , Maxstadt J J , McCarthy J , Nowak G W , Pardue J R , Richelieu M E , Saudarg D 
Published: February 2020

Abstract
Nine laboratories analyzed samples of whole grain, intermediate, and ready-to-eat products for ethylene dibromide (EDB) residues. Supplied samples of wheat, rice, and flour contained both fortified and incurred EDB; corn bread mix, baby cereal, and bread contained only fortified EDB. The whole grains and intermediates were analyzed by the same basic procedural steps as in the official method for multifumigants: They were extracted by soaking in acetone-water (5 + 1). The baby cereal and bread were analyzed by a modification of the Rains and Holder hexane co-distillation procedure. EDB was determined by electron capture gas chromatography operated with an SP-1000 column. All products contained 3 different levels of EDB and were analyzed as blind duplicates. Overall mean recoveries ranged from 85.2% for 69.6 ppb to 105.0% for 4.35 ppb, both in baby cereal. Interlaboratory relative standard deviations ranged from 5.7% for 869 ppb in wheat to 20.2% for 69.6 ppb in baby cereal, both fortified. Mean levels of incurred EDB in wheat, rice, and flour were 926.7, 982.0, and 49.9 ppb, respectively; corresponding relative standard deviations were 9.9, 7.7, and 13.1%. The method was adopted official first action.
Simplified Cleanup and Capillary Gas Chromatographic Analysis of Residues of Aldicarb and Its Oxidation Products in Chrysanthemum Leaves
Authors: McGarvey Brian D , Chiba Mikio , Broadbent A Bruce 
Published: February 2020

Abstract
An efficient simplified method for the extraction, cleanup, and capillary gas chromatographic (GC) analysis of residues of aldicarb, aldicarb sulfoxide, and aldicarb sulfone in chrysanthemum leaves is presented. Samples are extracted with methanol and cleaned up using columns consisting of 0.2 g Nuchar-Attaclay in disposable pipets. The 3 compounds are easily quantitated by capillary GC with splitless injection and thermionic-specific detection. Recovery of the 3 compounds at 2 levels from spiked leaves ranged from 74.3 to 90.9%. The detection limit of the GC analysis, with a 1 μL injection, is 0.01 μg/mL for aldicarb and aldicarb sulfone, and 0.06 p.g/mL for aldicarb sulfoxide.
Liquid Chromatographic Determination of Fluridone Aquatic Herbicide and Its Metabolite in Fish and Crayfish
Authors: West Sheldon D , Day Edgar W 
Published: February 2020

Abstract
A residue method is described for determination of the aquatic herbicide fluridone (1-methy1-3-phenyl-5-[3-(trifluoromethyl)phenyl]-4(1H)- pyridinone) and its metabolite (1-methy1-3-(4-hydroxyphenyl)-5-[3- (trifluoromethyl)phenyl]-4(1H)-pyridinone) in fish and crayfish tissues. Both compounds are extracted from tissues with methanol, and the extracts are subjected to acidic hydrolysis to release conjugated forms of fluridone and the metabolite. Sample extracts are purified by liquidliquid partitioning and Florisil Sep-Pak® column chromatography. Both compounds are separated and measured by reverse phase liquid chromatography with UV detection at 313 nm. In the absence of interfering peaks, the method has a detection limit of approximately 0.04 ppm of either compound. Overall, recoveries averaged 96% for fluridone and 78% for the metabolite for all tissue types combined.
Atomic Absorption Spectrometric Determination of Calcium, Copper, Iron, Magnesium, Manganese, Potassium, Sodium, and Zinc in Animal Feeding Stuffs: Interlaboratory Collaborative Studies
Authors: Ruig Willem G De ,   Collaborators:, Gast C H , Grimbergen A H M , Guis B , Hoekman B J , HoUman P C H , Hoogh P de , Huijbregts A W M , Leeuwen J van , Meer J M van der , Moh Oey Teng , Teunis G P , Vertregt N , Veen N G van der 
Published: February 2020

Abstract
A draft standard method is presented for the determination of Ca, Cu, Fe, Mg, Mn, K, Na, and Zn in animal feeding stuffs. The method specifies dry ashing of samples and detection by atomic absorption spectrometry (AAS). The applicability of the method for various concentrations of the elements was tested in a series of 3 collaborative studies. The feeding stuffs investigated include pulp pellets, grass, mixed feed, fish meal, milk powder, maize, sheep feed, lupin, milocorn, feather meal, and blood meal. Relative standard deviations, repeatability, and reproducibility are given. The reproducibility of the method was acceptable for the following approximate minimum quantities: Na and K, 1000 mg/kg; Ca and Mg, 100 mg/kg; Zn, Mn, and Cu, 10 mg/ kg; Fe, 10-200 mg/kg, depending on the product.
Thin Layer Chromatographic Identification of Phenothiazine Derivative Drugs: Interlaboratory Study
Authors: Steinbrecher Kurt ,   Collaborators:, Brunner C A , Newton J M , Newton R T , Robinette M L , Santiago A , Scroggins H S , Sics U , Wojtowicz E J 
Published: February 2020

Abstract
A thin layer chromatographic method for the identification of phenothiazine derivative drugs was studied collaboratively by 8 laboratories. Twenty phenothiazine drugs were examined by each collaborator. The identification scheme depends on the color of the sprayed spots and the Rf values relative to the Rf of chlorpromazine (RCHL) in 4 solvent systems. In 98.13% of the cases, a correct identification could be made; the remaining drugs were reduced to a choice between pairs of phenothiazines. With respect to chlorpromazine, the data showed a significant decrease in variability of RCHL values compared with Rf values in the 4 solvent systems.