bluuebunny/crossref_metadata_2025_split huggingface dataset:
High Pressure Liquid Chromatographic Determination of Fensulfothion: Collaborative Study
Authors: Owen Margie E ,   Collaborators:, Bennett O O , Chenery L T , Cohen C J , Freedlander R S , Gentry G M , Grimes G S , Hodgins W E , Meinen V J , Skelly N E , Wright D 
Published: February 2020

Abstract
A method for analyzing fensulfothion was tested by 10 collaborators. Formulations were dissolved, or extracted from inerts, in methanol. Benzophenone was used as an internal standard. The solution was diromatographed on a Partisil-10 ODS-2, or equivalent, reverse phase column, and detected at 230 nm. A mobile phase of methanol-water-phosphoric acid was used. The ratio of fensulfothion peak height to benzophenone peak height was calculated from the UV response and compared to the standard material for quantitation. A 15% granular formulation was analyzed as a matched pair. The results of one collaborator were outliers by the Dixon test. The coefficient of variation for the granular formulation was 1.6%. A matched pair of 63% spray concentrate samples was analyzed by 10 collaborators. The difference in results was an outlier for one collaborator; the coefficient of variation for the other collaborators was 1.5%. The method has been adopted official first action.
Analytical Methodology for Determining Glucosinolate Composition and Content
Authors: Mcgregor Douglas I , Mullin William J , Fenwick Gruffydd R 
Published: February 2020

Abstract
New analytical techniques and instrumentation and increased knowledge of the diversity and distribution of glucosinolates, the diversity of their enzymatically released products, and factors influencing their release, have led to significant advances in methodology for analysis of glucosinolates over the past three decades. However, many of the methods have been developed for specific agricultural crops or commodities and their particular glucosinolate compositions. They can only be applied to certain types of plant material or can detect and quantitate only certain glucosinolates or their products. Other methods have been designed to meet specific research, regulatory, or quality control requirements. This had necessitated sacrifice of either speed, simplicity, accuracy, precision, or the ability to distinguish different glucosinolates or their products. This review examines the methods available for sample preparation, identification, and quantitation of glucosinolates in light of current knowledge of their diversity, distribution, and chemistry. Consideration is given to the suitability of methods for rapid screening or precise, discriminating measurement, and to the standardization of methodology and reporting of results.
Compositional Analysis of Nonfat Dry Milk by Using Near Infrared Diffuse Reflectance Spectroscopy
Authors: Baer Robert J , Frank Joseph F , Loewenstein Morrison 
Published: February 2020

Abstract
Proximate data from 82 nonfat dry milk (NFDM) samples were correlated with near infrared reflectance (NIR) measurements. The best wavelengths for determining constituent concentrations were chosen from 19 preselected filters by using linear regression analysis. The correlation coefficient (r) was 0.971 and the standard error of prediction (SEP) was 0.274 when the predicted values (from NIR measurements) using the 3 wavelengths selected for determining moisture content were compared with laboratory values; r and SEP were 0.961 and 0.099, respectively, when the predicted values using the 4 wavelengths selected for fat content were compared with laboratory results; 0.887 and 0.594, respectively, using the 4 wavelengths selected for lactose content; 0.905 and 0.438 using the 8 wavelengths selected for protein (micro-Kjeldahl) content; and 0.911 and 0.509 using the 7 wavelengths selected for protein (dye binding). These data indicate that NIR can be used to estimate moisture, fat, lactose, and protein content of NFDM.
High Pressure Liquid Chromatographic Determination of Nitrofurazone and Furazolidone in Chicken and Pork Tissues
Authors: Sugden Edward A , Macintosh Agnes I , Vilim Arnost B 
Published: February 2020

Abstract
A high pressure liquid chromatographic (HPLC) procedure is presented for the determination of nitrofurazone and furazolidone in chicken and pork tissues in the 2-40 ppb range. Muscle, liver, and kidney are homogenized with cold methanol and water (50 + 50). Following methanol evaporation, the nitrofurans are partitioned into ethyl acetate and cleaned up on an alumina column. After elution with 20% methanol in ethyl acetate and evaporation to dryness, residues are determined by HPLC, using a reverse phase analytical column. Overall average recoveries for nitrofurazone and furazolidone were 65.7 and 73.5%, respectively. Average relative standard deviations of 11.9% (nitrofurazone) and 9.5% (furazolidone) at the 2 ppb level were achieved.
Quantitative Thin Layer Chromatographic Multi-Sulf onamide Screening Procedure
Authors: Thomas Michael H , Soroka Karen E , Thomas Sharon H 
Published: February 2020

Abstract
In-situ optical scanning of f luorescamine derivatives on thin layer silica gel plates provides a rapid method for the determination of multiple sulfonamides at levels below 0.1 ppm. Sample preparation is minimal. Homogenized liver or muscle is extracted with ethyl acetate and then back-extracted into 0.2M glycine buffer. After pH adjustment, the extract is washed with hexane and extracted with methylene chloride. The organic phase is evaporated to dryness and reconstituted in methanol. Pre-adsorbent layer silica gel plates are used for chromatography. The method has been applied to residues of sulfamethazine, sulfadimethoxine, sulfathiazole, sulfaquinoxaline, and sulfabromomethazine in cattle, swine, turkey, and duck tissues.
Quantitative Thin Layer Chromatographic Multi-Sulfonamide Screening Procedure: Collaborative Study
Authors: Thomas Michael H , Epstein Robert L , Ashworth Raymond B , Marks Harry ,   Collaborators:, Gonzales L , Hunter T , Kao C , Leadbetter M , Mitchell F , Patterson J , Soroka K E , Thomas S H , Willis B D 
Published: February 2020

Abstract
A thin layer chromatographic procedure suitable for detection of multiple sulfonamides at 0.1 ppm was studied in an interlaboratory collaborative study. Sulfamethazine, sulfadimethoxine, and sulfaquinoxaline were variously analyzed in liver and muscle tissues from swine, turkey, and duck. The average recovery for all drugs across all tissues was 95%. The corresponding repeatability and reproducibility were 7.7% and 10.5%, respectively.
Atomic Absorption Spectroscopic Analysis of Aluminum Sulfate-Type Soil Acidifiers: Mini-Collaborative Study
Authors: Knutson Ann ,   Collaborators:, Crawford D , Erickson M , Ingebrigtsen E , Jones C , Lambert T , Melton J , Sensmeier R , Wheeler W 
Published: February 2020

Abstract
Commercial brand aluminum sulfate soil acidifiers were subjected to a simple water extraction and analyzed for aluminum content by applying the principles of AOAC method 8.023. The study was designed to follow Youden's procedure for closely matched pairs and yielded results in close agreement. Statistical analysis, using 98% confidence limits, showed no outliers among analyses or laboratories. The combined Sr value was 0.1702, indicating satisfactory within-laboratory precision. The method has been adopted official first action.
Atomic Absorption Spectrophotometric Determination of Chelated Iron in Iron Chelate Concentrates: Collaborative Study
Authors: Silkey James R ,   Collaborators:, Angell S G , Bartunek K , Clark L W , Crawford D , Engvall D , Erickson M , Gordon D L , Hasselberger M L , Helmer J W , Jurgens D , Lambert T W , Melton J R , Miller C , Minyard J P , Sensmeier R K , Shatz W E , Stouffer N J , Tannenbaum S , Thorpe V A , Warren J D 
Published: February 2020

Abstract
An atomic absorption Spectrophotometric (AAS) method for determining chelated iron in iron chelate concentrates was collaboratively studied by 13 laboratories. Nonchelated iron was selectively precipitated as ferric hydroxide from an aqueous solution of the sample by adjusting to pH 8.5 with sodium hydroxide. A filtered portion of the sample solution was diluted with 0.5N HC1, and the iron was determined by AAS using standards containing disodium EDTA. Six pairs of iron chelate materials (12 samples) were analyzed and the average coefficients of variation were iron EDTA 3.52%, iron HEDTA 4.16%, iron DTPA 3.55%, iron EDDHA 3.52%, iron citrate 2.86%, and iron DPS 8.47%. The method has been adopted official first action.
Rapid Screening Procedure for Pesticides and Polychlorinated Biphenyls in Fish: Collaborative Study
Authors: Erney D Ronald ,   Collaborators:, Bong R L , Bulmer W , Hansen L B , Hennessy M K , Merser V , Pardue J R , Saxton W L 
Published: February 2020

Abstract
A simplified rapid method is presented to determine organochlorine pesticides and polychlorinated biphenyls in fish. Samples are mixed with sodium sulfate and blended with petroleum ether. A portion of the blend is placed on a miniaturized Florisil column and compounds are eluted with mixtures containing 6 and 15% ethyl ether in petroleum ether. Gas-liquid chromatography with electron capture detection comparable to the official methods (29.018) is used for determination of residues. Each of 7 collaborators reported results in duplicate for 10 samples containing one or more of the following compounds: p,p’-DDD,p,p’-DDE, p,p’-DDT, dieldrin, heptachlor epoxide, Aroclor 1254, and Aroclor 1260. Recoveries ranged from 79.3 to 100.7%. The coefficients of variation between laboratories ranged from 6.3 to 20.6%. This method allows up to 80% reduction in reagents and up to 50% reduction in analytical time, and requires less laboratory space than current official methods. The method has been adopted official first action.
Gas-Liquid Chromatographic Determination of Endosulfan Technical and Formulations: Collaborative Study1
Authors: Asshauer Jürgen , Watson Robert , Launer James E 
Published: February 2020

Abstract
The gas-liquid chromatographic determination of endosulfan technical and formulations was collaboratively studied with 11 laboratories. Fifteen samples were dissolved in toluene with di-(2-ethyl-hexyl)phthalate as the internal standard, chromatographed on a column of 10% OV-210, and detected by thermal conductivity. The average coefficients of variation were 0.55% for the 5 technical samples, 0.60% for the 5 wettable powders, and 0.68% for the 5 emulsifiable concentrates. The method has been adopted official first action.
Release of Lead and Cadmium: Comparison of Two Hot Leach Methods with a Room Temperature Method, Using Specially Glazed Ceramic Ware
Authors: Gould John H , Butler Stephen W , Steele Edward A 
Published: February 2020

Abstract
Oven and hot plate leach methods were compared with the official AOAC room temperature method for leaching Pb and Cd from specially glazed ceramic cookware. The hot leach methods released from 7 to 11 times more Pb and from 6 to 10 times more Cd after 24 h than did the AOAC procedure. Both hot leach methods specify a 2 h treatment with boiling 4% acetic acid, followed by 22 h of cooling at room temperature. The results show that essentially all of the Pb and Cd are released within 2 h, suggesting that the total contact time can be limited to 2 h to save laboratory space and time. The hot plate method is less difficult to perform and results in a continuous refluxing action. For these reasons, it is proposed as the hot leach method of choice.
Electron Capture Gas-Liquid Chromatographic Determination of Methyl Mercury in Fish and Shellfish: Collaborative Study
Authors: Hight Susan C , Capar Stephen G ,   Collaborators:, Anderson J , Brzezinski J , Cappon C J , Carr R , Kim E S , McNerney F G , Mitchell L , Newton J , Panaro K 
Published: February 2020

Abstract
A method for determining methyl mercury in fish and shellfish was collaboratively studied in 8 laboratories. Methyl mercury is isolated from acetonewashed, homogenized tissue by adding hydrochloric acid and extracting into benzene the methyl mercuric chloride that is formed. The benzene extract is concentrated and analyzed for methyl mercuric chloride by electron capture gas-liquid chromatography on 5% DEGS-PS treated with inorganic mercuric chloride solution. The quantitation limit for the method is 0.05 μg Hg/g. Each collaborator determined methyl mercury at 2 levels in blind duplicate samples of swordfish, tuna, oyster, and shrimp tissues. Both fortified and unfortified samples were analyzed. Methyl-bound mercury in the samples ranged from 0.15 to 148 μg Hg/g. The reproducibility coefficients of variation for the 8 samples ranged from 3 to 13%. The accuracy, measured by comparison to reference values, ranged from 99 to 120%. Reference values were determined in the Associate Referee's laboratory by replicate analyses of the fortified and unfortified samples. The method has been adopted official first action.
Electrothermal Atomic Absorption Spectrometric Determination of Selenium in Foods and Diets
Authors: Kumpulainen Jorma , Raittila Anna-Maria , Lehto Jari , Koivistoinen Pekka 
Published: February 2020

Abstract
The validity of 2 electrothermal atomic absorption spectrometric methods for determination of selenium in foods and diets was tested. By using 0.5% Ni(II) as a matrix modifier to prevent selenium losses during the ashing step, it was shown that selenium can be determined in samples containing ≥1 μg Se/g dry wt without organic extraction. The mean recovery tested, using NBS Bovine Liver, was 98%; recovery of added inorganic selenium in Bovine Liver matrix was 100%. In addition, this method gave values closest to the median value of all participating laboratories using hydride generation AAS or the spectrof luorometric method in a collaborative study on high selenium wheat, flour, and toast samples. For samples with concentrations &lt;1 μg Se/g dry wt, separation of selenium from interfering Fe and P ions by organic extraction was necessary. Using inorganic ,5 Se in meat and human milk matrixes, an ammonium pyrrolidine dithiocarbamate-methyl isobutyl ketone- extraction system with added Cu(II) as a matrix modifier yielded the best extraction recoveries, 97 and %%, respectively. Accuracy and precision of the method were tested using several official and unofficial biological standard materials. The mean accuracy was within 4% of the certified or best values of the standard materials and the day-to-day variation was 9%. The Se/Fe or Se/P interference limits proved to be low enough not to affect selenium determinations in practically all foods or diets. The practical detection limit of the method was 3 ng Se/g dry wt for 1.0 g dry wt samples. Approximately 20 duplicate determinations can be performed per day. In terms of sensitivity, accuracy, precision, and sample throughput, the tested method compares favorably with the best methods available.
Atomic Absorption Determination of Serum Copper: Collaborative Study
Authors: Osheim David L ,   Collaborators:, Casper H , Colvin W , Emerick R J , Everson R J , Hamar D , Hunter T , Jain A V , Reynolds J D , Roof J E , Rottinghaus G , Stahr H M , Torma L 
Published: February 2020

Abstract
Preliminary to conducting a collaborative study on a method for copper in serum, methods used by a selected group of laboratories were surveyed. The responding laboratories were supplied with a Youden pair of bovine serum samples and requested to use their current method for serum copper. Results of the analyses and the methods used were evaluated; hypotheses were developed in our laboratory to explain some of the interlaboratory variation. For the AAS method chosen, each of 12 collaborating laboratories analyzed one blind duplicate and 2 Youden pair of serum samples. A commercially available external control serum with a certified level of copper and a 1000 mg copper/L standard were also submitted. The method requires the serum to be diluted 1 + 1 with distilled water and the standards to be diluted with 10% glycerin to approximate the viscosity of the diluted serum. The intralaboratory coefficients of variation (CV) ranged from 2.24 to 4.40% and the interlaboratory CV ranged from 2.56% to 6.05%. The method has been adopted official first action.
Gas Chromatographic Determination of Ethanol in Wine: Collaborative Study
Authors: Caputi Arthur , Mooney Dennis P ,   Collaborators:, Cherolis J , Clements M , Crowell E A , Dowrie B , Fike S , Ho L , King J , Lerner M , Posey R , Ribeiro T , Rommel M , Scheidt R , Tolosa R , Vahl J 
Published: February 2020

Abstract
After a survey of laboratories using gas chromatographic procedures for wine alcohol analysis, 3 sets of columns and operating parameters were chosen on the basis of comparative reproducibility evaluations run in this laboratory. Fourteen collaborators participated in the study and were given their choice of any one of the 3 columns: (1) 1.8 m × 2 mm id glass, packed with 80-100 mesh Poropak QS; (2) 1.8 m × 2 mm id glass, packed with 0.2% Carbowax 1500 on 80-100 mesh Carbopack C; (3) 1.8 m × 6.35 mm copper, packed with 3% Carbowax 600 on 40-60 mesh Chromosorb T. Standards and samples were diluted 1:100 with 0.1% v/v n-butanol in water before analysis. Eight samples containing from 7.3 to 23.6% ethanol (v/v) were submitted as randomly coded duplicates along with a calibration standard and a practice sample. Two injections each of the diluted duplicates were made. On the basis of the reported results, 2 laboratories were rejected as outliers. The results of the remaining 12 collaborators showed an average reproducibility of 0.142 and a repeatability of 0.036. The method has been adopted official first action.
Gas Chromatographic Determination of Dimethylamine and Trimethylamine in Seafoods
Authors: Lundstrom Ronald C , Racicot Linda D 
Published: February 2020

Abstract
The volatile amines dimethylamine (DMA) and trimethylamine (TMA) are common degradation products of TMA-oxide in marine fish- Both compounds are used as important indicators of quality in seafoods. DMA is produced along with an equimolar quantity of formaldehyde by action of an endogenous enzyme found primarily in gadoid fish. TMA is produced in fresh, but not frozen seafoods by a bacterial enzyme. The current AOAC method for determination of TMA in fish is based on the colorimetric estimation of TMA as a picrate salt. This method is not specific for TMA; ammonia, monomethylamine, and DMA also form corresponding picrate salts. Gas chromatography provides a means of separating and quantitating the individual volatile amines. A simple perchloric acid extract of fish is neutralized with potassium hydroxide and extracted with benzene. The amines are then separated by gas chromatography on a porous polymer packed column and detected by using a nitrogen-phosphorus-specific flame ionization detector. The method provides simple, rapid simultaneous quantitation of DMA and TMA, and is applicable to a wide variety of seafoods.
Rapid High Pressure Liquid Chromatographic Determination of Amitriptyline Hydrochloride in Tablets and Injectables: Collaborative Study
Authors: Walker Samuel T ,   Collaborators:, Balbach R , Jefferson E , Jordan D , Lepore J , Lia U , Lookabaugh M , McCarthy J , Roberts S , Romano M , Uribe M 
Published: February 2020

Abstract
A previously reported high pressure liquid chromatographic method for the determination of amitriptyline hydrochloride in dosage forms was modified to permit its use as a stability-indicating method. The modified method, entailing a nitrile bonded microparticulate column, a methanol-0.005M ammonium acetate (90 + 10) mobile phase, and photometric detection at 239 nm, was collaboratively tested by 10 laboratories. Each collaborator received samples of synthetic and commercial tablets and injections. The recovery from a synthetic injection at the 10.06 mg/mL spiking level averaged 98.6%. The amount of declared found in commercial injections averaged 103.1%. The pooled reproducibility SD (CV%) and repeatability SD (CV%) were ± 2.12 (2.15) and ± 1.81 (1.84), respectively. The recovery from synthetic tablet composite at the 7.45% spiking level averaged 102.0%. The amount of declared found for commercial 25 mg and 100 mg tablets averaged 96.7 and 97.9%, respectively. The pooled reproducibility SD (CV%) and repeatability SD (CV%) for these 3 tablet samples were ± 1.89 (1.86) and ± 1.66 (1.64), respectively. Content uniformity analysis of commercial 25 mg and 100 mg tablets (n = 10) gave amounts of declared values averaging 100.5% (range 92.4-108.8%) and 99.3% (range 89.6-107.0%), respectively. The pooled reproducibility SD (CV%) and repeatability SD (CV%) were ± 3.23 (3.2) and ± 2.78 (2.8), respectively. A commercial injectable preparation spiked with dibenzosuberone was also collaboratively analyzed by a thin layer method. The method was adopted interim official first action.
Role of Anthranilic Acid in Background Levels of Sulfonamide in Porcine Livers when Determined by the Tishler Method
Authors: Parks Owen W 
Published: February 2020

Abstract
Anthranilic acid occurs in excised swine livers as a result of temperature abuse before and/or after freezing. The tryptophan metabolite is the major source of the variable non-sulf onamide background level frequently encountered in the Tishler method for determining sulfonamide residues in swine livers. Diazotized anthranilic acid reacts slowly with N-( naphthyl)ethylenediamine [k(s-1) = 5.79 (±0.07) × 10-5] and the final background level depends on the time elapsed between addition of the coupling agent and spectrophotometric determination. Kynurenine was tentatively identified as a minor source of the non-sulfonamide background level.
Modified Method for Electron Capture Gas-Liquid Chromatographic Determination of Diethylstilbestrol Residues in Urine of Fattened Bulls
Authors: Tirpenou Athanasios E , Kilikidis Stylianos D , Kamarianos Athanasios P 
Published: February 2020

Abstract
A gas-liquid chromatographic (GLC) method with electron capture (EC) detection was developed fof determining diethylstilbestrol residues in the urine of fattened bulls. Diethylstilbestrol (DES) is extracted into benzene, and then into IN sodium hydroxide. The pH of the phenolic fraction (alkaline phase) is adjusted to 10.2 and DES is extracted again into benzene. Sample extracts are cleaned up on silica gel. Trifluoroacetic anhydride (TFAA) is used as acylation reagent, and the derivatized sample is chromatographed on a 3% OV-17 column and measured with a 63Ni EC detector. The method is suitable for determining residues at levels as low as 2 ppb.
Flame Photometric Determination of K2O in Fertilizers: Collaborative Study
Authors: Kane Peter F , Stringham Rodger W ,   Collaborators:, Coggin D , Grigor S , Holmes J H , Johnson F J , Kirk L A , Lee C , Lehe C M , Neuman J F , Proska P , Ptak F L , Shideler R , Wall L L , Wheeler W L , Woodis T C 
Published: February 2020

Abstract
A collaborative study of the flame photometric determination of K2O in fertilizers has been conducted. The proposed method is intended to replace both the official manual flame method, 2.091, and the official automated method, 2.097. This is possible because the method is written in a general fashion in terms of instrument performance, rather than specifically for a particular instrument configuration. An example automated instrumental system in specific detail, which meets the general method requirements, is also included. Results for 20 samples from 11 laboratories were compared with results by the official STPB method, 2.102. Means and standard deviations of results are comparable between methods. Analysis of variance does not show any difference in methods. The method has been adopted official first action.