bluuebunny/crossref_metadata_2025_split huggingface dataset:
High-Performance Liquid Chromatographic Determination of Strychnine in Grain Baits
Authors: Bushway Rodney J , Cramer Christine W , Hanks Alan R , Colvin Billy M 
Published: February 2020

Abstract
A simple and rapid high-performance liquid chromatographic procedure is described for the determination of strychnine. Grain baits containing strychnine alkaloid are ground, mixed, and extracted by shaking with chloroform. Without further cleanup, extract nitrates are injected directly into a liquid chromatograph. Chromatography is complete within 7 min and peak heights are used for quantitation. Separations were made on a 30 cm × 4 mm id stainless steel column packed with μ Porasil (8–12 μm silica). The eluting solvent was methanolchloroform (10+90) at a flow rate of 2.0 ml/ min. Recovery of spiked samples ranged from 91.5 to 95.2%. Confirmation of strychnine from a commercial sample was made by high resolution mass spectrometry with mass agreement to 1.2 ppm.
Gas-Liquid Chromatographic Determination of Strychnine in Grain Baits
Authors: Hanks Alan R , Engdahl Barbara S , Colvin Billy M 
Published: February 2020

Abstract
A simple and rapid gas-liquid chromatographic procedure, using a 6’ × ¼“ glass column packed with 5% SE-30 on Chromosorb W (DMCS) and a flame ionization detector, is described. Grain baits containing strychnine alkaloid are ground, mixed, and extracted by shaking with chloroform containing an internal standard, 1,3,5-triphenylbenzene. Without further cleanup, extract nitrates are injected directly into a gas chromatograph. Peak height ratios are used for quantitation of strychnine. The analysis of commercial samples shows that the method compares well with a commonly employed ultraviolet spectrophotometric method; good precision, with recoveries ranging from 89.9 to 91.7%, is obtained in the analysis of prepared samples. The method is sensitive to 2 μg strychnine.
Separation of Rotenoids and the Determination of Rotenone in Pesticide Formulations by High-Perf ormance Liquid Chromatography
Authors: Bushway Rodney J , Engdahl Barbara S , Colvin Billy M , Hanks Alan R 
Published: February 2020

Abstract
The rotenoids deguelin, B-dihydrorotenone, dehydrorotenone, rotenone, 6αβ,12-rotenolone, and tephrosin were chromatogaphed on 8–12 μm silica. A mobile phase of chloroformisooctane (35+65) pumped at a flow rate of 1 ml/min through a 30 cm column was used and the absorbance of the eluate was monitored at 294 nm. Rotenone, B-dihydrorotenone, deguelin, and dehydrorotenone are completely resolved while 6αβ,12αβ-rotenolone and tephrosin chromatograph as one peak. This method has potential as a preparative separation technique for rotenoids. Also described is a procedure to quantitatively measure rotenone in pesticide formulations. Samples were extracted with chloroform and chromatographed at a flow of 2.5 ml/min. The method is rapid (rotenone is eluted in 12 min) and reproducible.
Measurement of Thiabendazole, Benomyl, and Folcidin Fungicides in Aqueous Suspensions
Authors: Miller Vernon L , Gould Charles J , Csonka Elizabeth 
Published: February 2020

Abstract
An improved procedure is described for the estimation of benomyl (methyl 1-(butylcarbamoyl)-2-benzimidazole carbamate), folcidin (methyl [l-([(5-cyanopentyl) amino] carbonyl)-1H-benzimidazole-2-yI] carbamate), and thiabendazole ( 2-(4’-thiazolyl)-benzimidazole) in the concentration range of 0.1–1.0 mg/ml. Representative samples of the fungicides in aqueous suspension are shaken with a chloroform solution of cupric acetate and l-dimethylamino- 2-propanol (sodium hydroxide is added in the case of thiabendazole) to produce a green color in the chloroform phase. The analysis may be completed by spectrophotometric measurement or by comparison with described artificial standards.
Determination of Ammonia Inhibition in Fabric Impregnated with Antimicrobials
Authors: Wilson Frederic H , Ball William 
Published: February 2020

Abstract
A new method is described for determining the presence or absence of ammonia produced by urealytic microorganisms, using fabric which has been treated with an antimicrobial. Circular disks of fabric treated with various concentrations of an antimicrobial are placed in the bottoms of snap-on lid petri dishes. Nutrient medium containing urea, an indicator, and a dilution of an overnight culture of Proteus mirabilis is applied to the fabric disks. The lids are snapped on and the dishes are incubated at 37°C. By examination of the fabric disks at regular intervals of time for a color change from white to red, one may determine whether the concentration of antimicrobial in the fabric is sufficient to inhibit the production of ammonia by a urealytic microorganism.
Direct Plating Method for Enumeration of Staphylococcus aureus: Collaborative Study
Authors: Baer Edward F , Messer James W , Leslie James E , Peeler James T 
Published: February 2020

Abstract
Considerable evidence has been published regarding the adverse effect of sodium chloride on physiologically impaired cells of Staphylococcus aureus, such as are to be expected in processed foods. A direct plating method for enumeration of S. aureus eliminating the use of sodium chloride was devised and subjected to collaborative study by 16 analysts. Results obtained by the direct plating method were compared to those obtained by the AOAC official first action method (46.036–46.040). Participating analysts examined duplicate samples at population levels of 91, 34, and 20 S. aureus/g. Coefficients of variation among analysts were considerably lower for the direct plating method (31, 81, and 48%, respectively) than for method 46.040 (59, 156, and 150%, respectively) at all 3 population levels. High coefficients of variation for the direct plating method at 2 of the 3 levels were due principally to low populations of S. aureus. The direct plating method has been adopted as official first action for general purpose use and use of method 46.036–46.040 has been restricted to raw food ingredients and nonprocessed foods.
Microwave Oven Method for Rapid Determination of Moisture in Meat
Authors: Pettinati Julio D 
Published: February 2020

Abstract
A new, rapid procedure was developed for moisture determination in meat. Results with the method were evaluated by comparative analysis with AOAC method 24.003(b). The new method is accurate, precise, and simple. Samples were prepared for drying by admixture with ferrous oxide and sodium chloride in glass weighing bottles and heating 2.5 mill in a domestic-type 1000 watt microwave oven. After heating, the residues were exposed 1 min in the stream of the oven chamber air blower, then covered and weighed. From comparative determinations on 67 meat samples containing from 3.5 to 77.9% moisture, meat type and moisture level were not significant (P = 0.05) sources of variation as determined by t-tests. Mean moisture content was 0.05% higher by the microwave oven method than by the AOAC method. Repeatability between duplicates was ± 0.47% moisture by microwave oven and ±0.45% by the AOAC method. Precision between paired determinations by the 2 methods was ±0.57% moisture. Both the t-test for significance (P = 0.05) and linear regression analysis of the comparative determinations indicated that the 2 methods were equivalent for determining moisture. Continued study of the method is recommended.
An Automated Total Protein Nitrogen Method
Authors: Wall Larry L , Gehrke Charles W 
Published: February 2020

Abstract
A rapid automated method for total protein nitrogen has been developed, using the Technicon AutoAnalyzer with block digestor. Ammonia is determined by the automated ammoniasalicylate reaction at a rate of 40 samples/hr. A number of variations in digestion parameters have been evaluated. Hydrogen peroxide was used as a digestion accelerator. A salt-acid ratio of 1:1 and a block temperature of 425°C were chosen. The catalysts evaluated included HgO, CuS04, Se02, and Ti02/CuS04. Maximum nitrogen recovery in the shortest time (30 mill) was achieved with HgO as the catalyst. The results from multiple analyses of 10 experimental samples of different refractoriness with the block digestor method, using HgO or CuS04 as a catalyst, compared well with the results by the official AOAC Kjeldahl method. The accuracy, precision, economy, and saving of space offered by the Missouri-Technicon block digestor method make this an attractive alternative to classical Kjeldahl analysis for large numbers of total protein determinations in samples of different refractoriness. The AutoAnalyzer cartridge manifold is simple and reproducible in its performance, and a large dilution of the sample is made on dialysis which eliminates the matrix effects from the sample digests. At least 250 samples can be analyzed in 9 hr with 1 instrumentation setup.
Comparative Study of Methods for the Extraction of Eleven Organophosphorus Pesticide Residues in Rice
Authors: Aoki Yoichi , Takeda Mitsuharu , Uchiyama Mitsuru 
Published: February 2020

Abstract
Several extraction methods are compared for the simultaneous analysis of organophosphorus pesticides in unpolished rice. Four stationary phases were used for the subsequent gas-liquid chromatographic (GLC) determination of the selected pesticides. Using 3 different GLC columns, 11 pesticides were completely separated and identified. The efficiency of the cleanup and the sensitivity of the analytical method were evaluated by using powdered unpolished rice samples fortified with the pesticides and also wheat and dried bean samples. Average recoveries ranged from 74.7% for disulfoton to 97.4% for malathion in unpolished rice and from 68.1% for disulfoton to 108.3% for malathion in other crops. The method described is applicable to the analysis of selected organophosphorus pesticide residues in unpolished rice, wheat, buckwheat, and dried beans.
Gas-Liquid Chromatographic Determination of Capsaicin
Authors: DiCecco Joseph J 
Published: February 2020

Abstract
A simple and accurate method has been developed for the quantitative determination of capsaicin in capsicum spices and their oleoresins. Capsaicin is extracted with acetone and separated from interfering substances, using an activated alumina column. The column is first eluted with acetone, and then the capsaicin is eluted with acetone-methanol-water (75+25+2). The capsaicin is quantitated by gas-liquid chromatography, using a Carbowax 20M-Teflon column and piperine as an internal standard. Results can be calculated as per cent capsaicin or Scoville units. Recovery of added capsaicin averaged 101%.
Collaborative Study of a Screening Method for the Detection of Aflatoxins in Mixed Feeds, Other Agricultural Products, and Foods
Authors: Romer Thomas R , Campbell Alfred D 
Published: February 2020

Abstract
A screening method for aflatoxins was collaboratively tested on 11 different agricultural and food products: white and yellow corn, peanuts, peanut butter, pistachio nuts, peanut meal, cottonseed meal, chicken, pig, and turkey starter rations, and dairy cattle feed. The method involves a rapid extraction and cleanup procedure followed by the detection of total aflatoxins (B1 + B2 + G1 + G2) as a fluorescent band on the Florisil layer of a Velasco-type minicolumn. The results of 32 collaborators from 10 different countries are presented. Samples containing 0, 5, 10, 15, 20, and 25 μg aflatoxins/kg were analyzed. Eighty-four per cent of the negative samples and 89% of the samples containing 10–25 μg total aflatoxins/kg were correctly identified. This method has been adopted as official first action for the detection of aflatoxins in corn, peanuts, peanut butter, peanut meal, cottonseed meal, mixed feeds, and pistachio nuts.
Detection of Volatile Solvents in Gastric Contents by Gas Phase Infrared Spectrophotometry
Authors: Fastlich Eugene 
Published: February 2020

Abstract
A standard procedure for the identification of volatile solvents in the gas phase by infrared spectrophotometry has been modified and applied to the analysis of gastric contents. A 10 ml sample of the vapor from the gastric aspirate is removed with a hypodermic syringe, injected into a gas cell at reduced pressure, and scanned on a spectrophotometer from 2.5 to 15 nm. The sample is then identified by comparison with known reference spectra. Solvent concentrations can be estimated by comparing the ratios of the major peaks.
Collaborative Study of an Automated Method for the Determination of Crude Protein in Animal Feeds
Authors: Noel Rodney J 
Published: February 2020

Abstract
An automated macro Kjeldahl instrument determines per cent protein at the rate of 20 samples/hr. The methodology involved is similar to the present official final action Kjeldahl method, sec. 7.016. The 2 methods were compared in a collaborative study. Sixteen animal feeds, 4 meats, tryptophan, ammonium dihydrogen phosphate NBS standard, and ammonium sulfate primary standard were analyzed by the participating laboratories. The data were treated statistically and the results showed good agreement between the 2 methods. The automated method has been adopted as official first action for the determination of crude protein in feeds, plants, and cereal foods.
Collaborative Study of Effect of Light on Cadmium and Lead Leaching from Ceramic Glazes
Authors: Krinitz Benjamin , Holak Walter 
Published: February 2020

Abstract
A limited interlaboratory study was carried out to determine the effect of lighting conditions on the release of cadmium from ceramic glazes by 4% acetic acid. Cadmium release increased with increased exposure to light. Further interlaboratory study on plates manufactured under controlled conditions showed that if temperature, intensity of illumination, and time of exposure are specified, reproducible results for leaching of both lead and cadmium can be obtained. A modification of the official AOAC method, 25.031–25.034, to increase sensitivity was collaboratively studied by 8 laboratories. Each received 6 solutions of lead in 4% acetic acid (3 sets of blind duplicates at the 0.1, 0.5, and 0.8 μg/ml levels) plus a reagent blank. Average recoveries were 0.1006, 0.5056, and 0.8194 μg/ml, respectively, with coefficients of variation of 11.4, 3.3, and 2.8%, respectively. The proposed modification is simple, rapid, and accurate. The modification has been adopted as official first action, and a parameter for exposure to light during extraction has been included in the method.
Partition Chromatographic Separation of Pesticide Residues from Fats
Authors: Dale William E , Miles James W 
Published: February 2020

Abstract
A simple, rapid, and efficient partitioning column consisting of acetonitrile on Florisil has been developed for the separation of pesticides from fish, beef, and butter fat. The efficiency of the cleanup column is between 97 and 100%. Nine pesticides having partition coefficients between n-hexane and acetonitrile of ≤0.05 were satisfactorily separated from fat with good recoveries. When the column was used to clean up temephos in a fish extract, 99.91% of the fat was eluted with 20 ml n-hexane with no loss of the pesticide.
Determination of Quinomethionate (6-Methylquinoline-2,3-diyldithiocarbonate) Residues in Crops by In Situ Fluorometry
Authors: Francoeur Yves , Mallet Victorin 
Published: February 2020

Abstract
A simple method is described for the quantitative determination of quinomethionate (6-methylquinoline-2,3-diyldithiocarbonate) in crops. The pesticide residue is extracted with acetonitrile and partitioned in petroleum ether. After separation from the co-extractives by thin layer chromatography (TLC), the fluorescence is measured directly on a silica gel TLC plate. An average of 89% recovery is obtained at the 0.05 ppm level in apples, peaches, pears, and tomatoes.
An Indirect Determination of Biuret in Mixed Fertilizers and Urea by Atomic Absorption Spectrophotometry
Authors: Woodis Terry C , Hunter G Bradley , Johnson Frank J 
Published: February 2020

Abstract
An indirect method for determining biuret in mixed fertilizers and urea has been developed. An alcoholic solution of biuret and copper is treated with a strong base to form a biuret-copper complex and to precipitate the excess copper. After separation of the precipitate, the complexed copper in solution is determined by atomic absorption spectrophotometry. Even though a stoichiometric ratio did not exist, a linear relationship between copper and biuret was obtained and was utilized for the determination of biuret. The proposed method is accurate and proved rugged for the range of biuret normally found in mixed fertilizers and urea when subjected to Youden’s ruggedness test.
4,4′-(Diazoamino)-bis(5-methoxy-2-methylbenzenesulfonic Acid): Preparation and Determination in FD&C Red No. 40
Authors: Bailey John E , Cox Elizabeth A 
Published: February 2020

Abstract
4,4′-(Diazoamino)-bis(5-methoxy-2-methylbenzenesulfonic acid) (CSAT) has been found in samples of FD&C Red No. 40 submitted for certification, using high-pressure liquid chromatography (HPLC). CSAT is synthesized by diazotizing cresidine sulfonic acid (CSA) and coupling the diazonium salt with undiazotized CSA in the presence of sodium acetate. A method for quantitative determination of CSAT in FD&C Red No. 40, using HPLC and an untested method of correcting for interfering compounds, is presented.
Collaborative Study of an Enzymatic Digestion Method for the Isolation of Light Filth from Ground Beef or Hamburger
Authors: Alioto Phillip , Andreas Mary 
Published: February 2020

Abstract
Collaborative results are presented for a proposed method for light filth extraction from ground beef or hamburger. The method involves enzymatic digestion, wet sieving, and extraction with light mineral oil from 40% isopropanol. Recoveries are good and filter papers are clean. This method has been adopted as official first action.
Analysis of Bromide Ion in Wine by Ion Selective Electrode
Authors: Graf James E , Vaughn Troy E , Kipp William H 
Published: February 2020

Abstract
The use of the bromide ion selective electrode for the determination of bromide ion in wine has been found to be rapid and reliable. The method has been used for still wines and carbonated wines and is applicable to all wines regardless of their country of origin. The method consists of treating a 50 ml aliquot of wine with 2 ml each of 3.75M H3PO4, saturated KNO3, and 1M CuSO4. After 10 min the electrodes are immersed in the samples and a millivolt reading is obtained. One hundred μl 500 ppm bromide ion standard is added and the millivolt reading is taken. Bromide ion concentration in the wine = (CΔ × 1)/((antilog ΔE/S) − 1) where CΔ = 1, ΔE = the change in potential expressed in millivolts, and S = the electrode slope.
Identification of Some Analogs of the Hallucinogen Phencyclidine
Authors: Bailey Keith , Gagné Denise R , Pike Richard K 
Published: February 2020

Abstract
The drugs 1-[1-(2-thienyl)cyclohexyl]piperidine, 1-[1-(2-thienyl) cyclohexyl] morpholine, 1-[1-(2-thienyl)cyclohexyl] pyrrolidine, 1-(1-phenylcyclohexyl) morpholine, and 1-(1-phenylcyclohexyl) pyrrolidine are identified by spectroscopic techniques. The ultraviolet and proton magnetic resonance spectra of analogs are similar, but mass and infrared spectra are distinctly different, and reference spectra are provided. Gas-liquid and thin layer chromatographic systems for the analysis are discussed.
Collaborative Study of a Column Chromatographic Method for Bendroflumethiazide and Cyclothiazide
Authors: Fazzari Frank R 
Published: February 2020

Abstract
Bendroflumethiazide and cyclothiazide are eluted from a sodium carbonate column with chloroform-acetic acid (98+2) and are measured directly by ultraviolet spectrophotometry. The method was collaboratively studied by 8 analysts. The average per cent recovery and standard deviations for simulated mixes of bendroflumethiazide and cyclothiazide were 99.61±0.94 and 98.85±3.28, respectively. For commercial preparations the respective values were 99.52±0.78 and 99.3±1.97. The method has been adopted as official first action for the determination of bendroflumethiazide.
Determination of Total Nitrogen in Plant Tissue, Using a Block Digestor
Authors: Isaac Robert A , Johnson William C 
Published: February 2020

Abstract
The determination of total nitrogen in plant tissue using a Technicon BD-40 digestor provided one of the best analytical tools for Kjeldahl digestion. The method is rapid and precise and utilizes the minimum laboratory space for such operations. The ammonia found is determined using the automated continuous flow methodology of an AutoAnalyzer. Up to 300 samples/day may be analyzed with a single system. Recovery of added nitrogen was 100.9±4.1%. Comparison with AOAC method 2.049 gave an average difference of 0.02% nitrogen for 8 plant tissues.
Quantitation of o- and p-Sulfamoylbenzoic Acids in Commercial Saccharin by High-Performance Liquid Chromatography
Authors: Nelson James J 
Published: February 2020

Abstract
Quantitation of o- and p-sulfamoylbenzoic acid residues in saccharin and its sodium salt is achieved by a method comprising methanolic extraction and high-performance ion exchange chromatography. A commercially available anion exchange column was employed with an aqueous buffered (pH 9.2) mobile phase. As little as 80 ppm of the ortho-isomer and 25 ppm of the para-isomer can be accurately determined. The levels of detectability (2 times noise) are estimated as 8 ppm (0.16 μg on column) and 2.5 ppm (0.05 μg on column), respectively. Recoveries from saccharin ranged from 92.7 to 96.5% (ortho) and from 92.2 to 103.3% (para). Recoveries from the sodium salt ranged from 93.1 to 104.4% (ortho) and from 93.5 to 97.8% (para). Of 9 other potential saccharin impurities tested separately, only one was found to interfere slightly in the chromatographic part of the procedure.
Gas-Liquid Chromatographic Determination of Famphur and Its Oxygen Analog in Tissues of Reindeer and Cattle
Authors: Ivey Marcellus C 
Published: February 2020

Abstract
A gas chromatograph equipped with a flame photometric detector operating in the phosphorus mode provided a sensitive method for determining residues of famphur, O,O-dimethyl O-[p-(dimethylsulfamoyl)phenyl]phosphorothioate, and its oxygen analog in reindeer and cattle tissues. With extraction and cleanup, 0.025 ppm famphur and 0.06 ppm oxygen analog could be detected in the body tissues. Recoveries of 73–100% were obtained from fat, muscle, liver, and kidney.
Collaborative Study of the Colorimetric Determination of Nitrate and Nitrite in Cheese
Authors: Hamilton James E 
Published: February 2020

Abstract
A quantitative colorimetric method for the determination of nitrate and nitrite in cheese has been subjected to collaborative study. The method includes clarification of an aqueous extract of cheese with zinc hydroxide, reduction of nitrate to nitrite via a spongy cadmium column (the nitrite originally present is unaltered), diazotization of sulfanilic acid with the nitrite, and coupling with 1-naphthylamine hydrochloride to form a pink azo dye whose absorbance is measured at 522 nm. The spectrophotometric responses are compared to a standard curve. In samples containing both nitrate and nitrite, nitrate is determined by difference. A standard deviation of 5.5 was obtained (5 of 6 collaborators) when a cheese sample spiked with 276 ppm sodium nitrate was analyzed by the method. The method has been adopted as official first action.
Correction of Refractometer Sucrose Readings for Citric Acid Content in Frozen Concentrate for Lemonade
Authors: Yeatman John N , Senzel Alan J , Springer Janet A 
Published: February 2020

Abstract
Computer-generated regression equations to express citric acid corrections for refractometer sucrose readings in frozen concentrate for lemonade were developed from experimentally determined values for °Brix, soluble solids, and citric acid content. These equations have been included in a method for the calculation of soluble solids in frozen concentrate for lemonade. The method has been adopted as official first action.