bluuebunny/crossref_metadata_2025_split huggingface dataset:
High Pressure Liquid Chromatographic Determination of the Intermediates/Side Reaction Products in FD&C Red No. 2 and FD&C Yellow No. 5 : Statistical Analysis of Instrument Response
Authors: Bailey Catherine J , Cox Elizabeth A , Springer Janet A 
Published: February 2020

Abstract
The statistical methods of regression analysis are applied to calibration data obtained by high pressure liquid chromatographic analysis for the intermediates and side reaction products of FD&C Yellow No. 5 and the former FD&C Red No. 2. Equations are presented which allow calculation of the regression line equation, correlation coefficient, the upper prediction limit on the blank (YUB)? t n e limit of detection in terms of concentration (XLD), response above which quantitation is performed (YQ) , and prediction intervals for a specific response. The HPLC methods for FD&C Yellow No. 5 and the former FD&C Red No. 2 are evaluated based on those calculations.
Further Studies on the Colorimetric Determination of Ronidazole in Feeds
Authors: Fink David W , Pivnichny James V , Shim Jung-Sook K , Tolan John W 
Published: February 2020

Abstract
A previously published colorimetric method for determining ronidazole, (l-methyl-5-nitroimidazoI- 2-yl) methyl carbamate, can be used as an analytical technique for measuring the stability of this drug in medicated feeds. Although the color reaction per se is not selective, elution profiles of ronidazole and its demonstrated hydrolytic degradation product, l-methyl-2-hydroxymethyl- 5-nitroimidazoIe, show that the chromatographic separation used in the sample preparation efficiently isolates the drug from the degradation product. No interference was found in feeds containing 0.010% ronidazole and up to 0.010% degradation product.
Column Chromatographic Determination of Mirex, Photomirex, and Poly chlorinated Biphenyls in Lake Sediments
Authors: Chau Alfred S Y , Babjak Ludwig J 
Published: February 2020

Abstract
Mirex (dodecachlorooctahydro -1,3,4 - metheno-2H-cyclobuta[cd]pentalene) and photomirex (8-monohydromirex) are separated from interfering polychlorinated biphenyls (PCBs) in lake sediments. Sediment samples were extracted with acetone-hexane (1+1) in an ultrasonic apparatus and the extracts were cleaned up on conventional Florisil columns. A charcoal-polyurethane column was used to quantitatively separate Mirex and photomirex from PCBs. Recoveries of Mirex, photomirex, and PCBs from the spiked sediments were each &gt;95% at 0.1 to 3 ppb levels.
Ultraviolet Spectrophotometric Determination of Benzoic Acid in Soy Sauce
Authors: Goo Reginald K S , Wakatsuki Helen , Kanai Hiromitsu 
Published: February 2020

Abstract
Proteins and other interfering substances are precipitated from soy sauce, using sodium tungstate under acidic conditions. After centrifugation, the supernate is successively extracted with ethyl ether to isolate the benzoic acid in the organic solvent. The ettiyl ether extract is washed with dilute HC1. Benzoic acid is then quantitatively determined by ultraviolet spectrophotometry. Recovery of sodium benzoate added to soy sauce ranged from 94 to 104%.
Sample Homogenization Procedure for Determination of Lead in Canned Foods
Authors: Jones John W , Boyer Kenneth W 
Published: February 2020

Abstract
To improve the homogeneity of canned foods before Pb determination, composited samples or single can contents (150—500 g) are treated with an equal weight of dilute nitric acid, and then thoroughly blended in a high efficiency, probe-type Polytron homogenizer; subsamples are then either dry-ashed or wet-ashed in preparation for analysis. Within-can variability is reduced from the 20—50% coefficient of variation range obtained with conventional blending procedures to a coefficient of variation of &lt;5% by using the procedure described. Precision data for Pb, using both the probe-type and conventional blade-type homogenizers, are compared. The procedure described for Pb determination was used to analyze a number of canned products. Data indicate that the Polytron plus dilute acid procedure improves overall Pb homogeneity for subtle as well as severe initial Pb heterogeneity.
Rapid Automated Turbidimetric Assay for Chlortetracycline Hydrochloride, Using Leuconostoc mesenteroides as the Test Organism
Authors: Mueller Dorothy L , Reed Shirley J , Barkate John A 
Published: February 2020

Abstract
A rapid turbidimetric assay has been developed for chlortetracycline hydrochloride (CTC-HC1) in finished animal feeds and feed supplements, using Leuconostoc mesenteroides as the test organism. Two modifications are presented: The incubation period of modification 1 is 2.5 hr and the sensitivity of the assay is 0.03 μg CTC-HC1/assay tube. Modification 2 has a sensitivity of 0.01 μg CTC-HC1/assay tube and requires an incubation period of 3.5 hr. For 21 feed formulations, the turbidimetric method recovered 95.7% of label claim. Recoveries of CTC-HC1 standards from the same feeds ranged from 93.4 to 134% with a mean of 103% . The relative standard deviation among day-to-day duplicates is 3.50% for the faster modification and 1.63% for the more sensitive modification.
High Pressure Liquid Chromatographic Determination of Sugars in Various Food Products
Authors: Dunmire David L , Otto Susan E 
Published: February 2020

Abstract
A high pressure liquid chromatographic (HPLC) method has been developed which is fast, simple, specific, and reliable over a wide range of sugar concentrations in a variety of food matrices. With few exceptions, sample preparation is simple, requiring only a waterethanol extraction, followed by a rapid minicolumn cleanup before injection into the HPLC system. The majority of samples can be prepared for analysis within 1—1½ hr, and the following sugars are separated in &lt;45 min: fructose, glucose, sucrose, maltose, lactose, melibiose, raffinose, and stachyose. This method is applicable to baby foods, cereals, chocolate products, chocolate sirups, cookies, health food products, molasses, preserves, processed fruits, and soy protein products.
Identification and Gas-Liquid Chromatographic Determination of Aryl Phosphate Residues in Environmental Samples
Authors: Lombardo Pasquale , Egry Ivan J 
Published: February 2020

Abstract
Aryl phosphates are widely used as flame retardant plasticizers and hydraulic fluids. Laboratory exposures of rainbow trout to a commercial phosphate hydraulic fluid in a flow-through system resulted in substantial biomagnification. Aryl phosphate residues in fish are extracted and cleaned up by the AOAC method for pesticides in fatty foods, and are detected by phosphorus-selective gas-liquid chromatography. Residues of several aryl phosphate mixtures were detected in fish near industrial sites at concentrations ranging from 0.04 to 1 ppm (edible portion basis).
High Pressure Liquid Chromatographic Determination of 3,5-Dimethyl-4-(Methylthio) phenyl Methylcarbamate in Formulations
Authors: Fuzesi Martha 
Published: February 2020

Abstract
Methiocarb (3,5 - dimethyl - 4 - (methylthio) - phenyl methylcarbamate) is extracted from commercial pesticide formulations with methanol, and carbaryl is added as an internal standard. The sample is chromatographed by reverse phase high pressure liquid chromatography, with ultraviolet detection at 254 nm. Peak height ratios are used for quantitative measurement. The method is rapid and accurate, and recoveries from laboratory-prepared formulations averaged 100.8%.
Gas-Liquid Chromatographic Method for the Analysis of Technical Dichlobenil and Its Formulations:1 Collaborative Study
Authors: Bemmel Pieter Van , Rossum Bram Van , Martijn Albertus 
Published: February 2020

Abstract
A gas-liquid chromatographic method for determining dichlobenil in technical material and formulations was collaboratively studied by 7 laboratories. Five samples were chromatographed on a 10% Carbowax 20M column with methyl myristate as the internal standard and flame ionization detection. The estimates of the repeatability (different analysts) and the reproducibility, expressed as coefficients of variation, were, respectively, 0.8 and 1.0% for the technical sample, 1.4 and 1.7% for the wettable powder, and 3.5 and 4.6% for the granular formulations. This method was adopted as a full CIPAC-AOAC method.
Rapid Spectrophotometric Method for Determination of Benzoic and Cinnamic Acids in Balsam Tolu
Authors: El-Masry Sawsan 
Published: February 2020

Abstract
A rapid spectrophotometric method is described for the individual assay of balsamic acids. The method has been applied to the determination of benzoic and cinnamic acids in samples of balsam tolu. Compared with the British Pharmaceutical Codex procedure, the recommended method combines the advantages of a faster analysis and the determination of individual balsamic acids without the need of organic solvent extraction. The sample is saponified and purified and the 2 balsamic acids are determined spectrophotometrically using the 2-wavelength method of analysis. The method has been successfully applied to the analysis of 4 batches of balsam tolu. The relative standard deviation is 1.85%.
Isolation and Concentration of Organophosphorus Pesticides from Drinking Water at the ng/L Level, Using Macroreticular Resin
Authors: Lebel Guy L , Williams David T , Griffith Georgina , Benoit Frank M 
Published: February 2020

Abstract
A screening method has been developed for determining organophosphorus pesticides at ng/L levels in drinking water. Sixteen organophosphorus pesticides, diazinon, diazinon-oxon, dimethoate, ronnel, β-phosphamidon, methyl parathion, ethyl parathion, malathion, chlorpyrifos, fenitrothion, ruelene, methidathion, ethion, EPN, phosalone, and phosmet, were extracted by Amberlite XAD-2 resin from 100 and 200 L drinking water previously spiked with these pesticides. The pesticides were eluted from the XAD-2 resin with acetone-hexane (15+85). The concentrated extract was analyzed by gas chromatography using a nitrogen-phosphorus selective detector and by gas chromatographymass spectrometry using selected ion monitoring. Recoveries at the 10 and 100 ng/L spiking levels were greater than 90%, except recoveries for dimethoate and phosphamidon were 37 and 42 %, respectively. The analysis of 300 L Ottawa tap water showed no detectable amounts (&lt;1 ng/L) of any of the 16 organophosphorus pesticides.
Malt Beverages and Brewing Materials: Calculation of Carbohydrate Content and Caloric Content
Authors: West Dwight B 
Published: February 2020

Abstract
The American Society of Brewing Chemists (ASBS) has released one new procedure and one change in a present procedure. A new method for calculating the carbohydrate content of malt beverages, after determining the specific gravity, real extract, protein, and ash contents by AOAC methods, is presented. The method is applicable to either weight or volume amounts of malt beverages. Two changes are presented in method 10.027, caloric content of malt beverages: (1) the calorie factor for grams of ethanol is changed from 7.0 to 6.9, and (2) the ash content of the malt beverage is subtracted from the real extract before calculating the calories of the extract. The 2 changes are needed to make the caloric calculation more precise.
Flotation Technique for Quantitative Determination of Mite Populations in Powdered and Compacted Foodstuffs
Authors: Thind Bharat B , Griffiths Donald A 
Published: February 2020

Abstract
Samples are preheated in 25% aqueous ethanol at 65 °C for 5 min. A specially designed flotation flask and solvent mixture of kerosenetetralin (1+1) is used to form an interface with 25% aqueous ethanol. Mites, insects, and insect fragments are separated from vegetative material by an overflow method. Trials incorporating a known number of mites in samples of pigmeal indicate that at an infestation level of 1000 mites/kg the method always recovered 70% of the population and at 2000 mites/kg, 75%. The method permits collection of mite specimens for microscopic examination as well as allowing differentiation between live and long-dead insects. It does not use highly volatile solvents or corrosive acids. The apparatus has been successfully tested for quantitatively determining mite populations in flour, dried skimmed milk, animal feedstuffs, soya meal, wheat, rape seed, dates, and house dust. It has also been used to estimate insect contamination in packaged dates.
Assay of Formulations Containing 2,4-D and/or Picloram by Direct Injection High Pressure Liquid Chromatography
Authors: Stevens Timothy S 
Published: February 2020

Abstract
A rapid and precise fully automated, direct injection high pressure liquid chromatographic method is described for assaying liquid formulations of 2,4-dichlorophenoxyacetic acid (2,4-D) and/or picloram (4-amino-3,5,6-trichloropicolinic acid). The method is specific for the 2,4-D and picloram isomers. No sample preparation is needed, triplicate assays can be performed in 1 hr, and precision is about 1% relative at the 95% confidence level. Compounds are separated on a 9 mm id reverse phase microparticulate column with an eluant of ace* tonitrile-water (1+4) , buffered at pH 2.95. No bias was observed between this method and the official final action HPLC method for picloram and 2,4-D in picloram-2,4-D mixtures, 6.B09-6.B12.
Determination of Vitamin Bi in Pharmaceutical Preparations Using a Lead Ion Selective Electrode and Atomic Absorption Spectroscopy
Authors: Hassan Saad S M , Zaki Mohamed T , Eldesouki Mohamed H 
Published: February 2020

Abstract
Simple, rapid, and accurate methods have been developed for determining vitamin Bx in pharmaceutical preparations without prior separation of the vitamin. The methods are based on the desulfurization reaction with potassium plumbite and measurement of the unreacted lead (II) ions at 217 nm using atomic absorption spectroscopy (AAS), or by titration with EDTA at pH 4.5 with the lead ion selective electrode and Gran's plot. The results compare favorably with those obtained using the USP fluorometric method. Recoveries of pure vitamin Bx averaged 99.1%, with a standard deviation of 0.8%, and 99.0%, with a standard deviation of 0.7%, for the AAS and ion selective electrode procedures, respectively.
Bathocuproine Method for Determining Water-Soluble Copper in Water-Insoluble Copper Fungicides:1 CIPAC Collaborative Study
Authors: Sánchez-Rasero F , Henriet J 
Published: February 2020

Abstract
A spectrophotometry bathocuproine method for determining water-soluble copper in copper oxychloride and cuprous oxide was collaboratively studied by 9 laboratories. The samples are dispersed in deionized water. After centrifugation and nitration, the water-soluble copper in the nitrate is reduced to Cu+ with ascorbic acid. After the bathocuproine reagent is added, the colored complex is extracted with chloroform and its absorption is measured at 465 nm and compared to a standard calibration curve. Satisfactory results were obtained: Both the repeatability and the reproducibility standard deviations ranged from 0.002 to 0.04; the coefficients of variation ranged from 7.63 to 12.71.
Spectrophotometric Determination of Benomyl and Methyl 2-Benzimidazole Carbamate in Product Formulations by a Low Temperature-Solubilization Technique
Authors: Chiba Mikio 
Published: February 2020

Abstract
A rapid spectrophotometric method has been developed to determine benomyl (methyl l-(butylcarbamoyl)- 2-benzimidazole carbamate) and methyl 2-benzimidazole carbamate (MBC) simultaneously in wettable powder formulations by solubilizing all the ingredients in a special solvent mixture. A special solvent mixture consisting of chloroform, dioxane, and water was prepared at room temperature; the mixture was cooled to 1°C and used to dissolve samples. The degradation of benomyl, unavoidable at 25°C, was eliminated by this cold temperature operation. Absorbance of the diluted solution was measured at 294 and 286 nm in a ratiorecording spectrophotometer, and individual concentrations of benomyl and MBC were calculated by a simple equation. An alternative method has been suggested for users of nonautomatic scanning spectrophotometers. re-Butyl isocyanate was used to stabilize benomyl in standard solutions and to re-form benomyl from MBC. Analyses were conducted on Benlate® 50% WP and Benlate® 10% WP mixed with captan 50%. Most 50% WP formulations contained 50-55% intact benomyl and 0.4-2.3% MBC. Benomyl was stable in those WP formulations, although both time and conditions of storage varied significantly. Most 10% WP samples contained 8–12% benomyl and 0.1–2.9% MBC.
Thin Layer Chromatography Combined with Color Spot Test Reactions for Preliminary Identification of Papaveraceous Alkaloids
Authors: Engelke Beatriz Ferreira , Vincent Phillip G 
Published: February 2020

Abstract
Thin layer chromatography (TLC) and color spot test reagents (CSTR) were used consecutively to identify isolated papaveraceous alkaloids. Fourteen alkaloid standards were spotted on fluorescent and nonfluorescent silica gel G TLC plates and developed with 3 solvent systems. Spots were evaluated by appearance under daylight, appearance under short wavelength ultraviolet light, color developed by 2 spray reagents, and migration. Eighteen crystalline alkaloids were tested on spot plates with Frohde, Ferreira, Marquis plus oxidant, Mecke, and ferric oxidizing reagents. Colors developed were evaluated as a function of time. Color names were standardized by comparison with color plates from the Centroid Color Charts issued by the Intersociety Color Council of the National Bureau of Standards. TLC separation followed by CSTR is a useful analytical procedure for preliminary identification of alkaloids extracted from tissues of papaveraceae.
Extraction of Light Filth from Ground Nutmeg: Collaborative Study
Authors: Thrasher Joel J 
Published: February 2020

Abstract
The official method for extracting light filth from ground nutmeg, 44.116, gives variable recoveries of filth elements and results in large amounts of interfering plant material in the light filth extraction. A new method has been developed using a chloroform pretreatment for heavy filth followed by a water-40% isopropanol- mineral oil flotation of light filth. A comparison of the methods in the collaborative study showed a higher recovery of insect fragments, 90.6 vs. 65.2%, and of rodent hairs, 86.5 vs. 66.5%, for the new method over the present official first action method, 44.116. Frothing, an additional problem with the official method, has been reduced by the new method. The new method has been adopted as official first action to replace the existing method.
Fish Species Identification by Thin Layer Isoelectric Focusing
Authors: Lundstrom Ronald C 
Published: February 2020

Abstract
Conventional electrophoretic techniques generally lack the resolution and reproducibility needed for the reliable identification of fish species. Variations in stabilizing media composition, sample application technique, separation time, applied voltage or current, and the analyst’s skill all affect the protein pattern. Thin layer polyacrylamide gel isoelectric focusing (TLIEF), a high resolution protein separation technique, has been applied to the identification of fish species. Sarcoplasmic proteins are separated according to their isoelectric points in a stable, reproducible ptT^gradient. Protein patterns for 12 species of fish are compared in 4.0% polyacrylamide gels with pH 4.0–6.0 and pH 3.5–10 gradients. Similar patterns are shown in commercially prepared 5.0% polyacrylamide gels with pH 4.0–6.5 and pH 3.5–9.5 gradients (LKB PAG plates). The protein patterns are reproducible in each pH gradient and also correlate well between user-prepared and commercially prepared gels. The inherent high resolution and excellent reproducibility of TLIEF should allow the positive identification of fish species without the costly procedure of using known species as standards.
Determination of Chlorinated Pesticide Residues in Foods. I. Rapid Screening Method for Chlorinated Pesticides in Milk
Authors: Suzuki Takashi , Ishikawa Kiyoshi , Sato Nobutoshi , Sakai Kei-Ichi 
Published: February 2020

Abstract
A rapid analytical method for determining chlorinated pesticide residues in milk was developed. Thirteen pesticides were almost completely extracted. Ten mL samples of fortified milk were extracted 3 times with 20 mL portions of n-hexane as follows: (A) in the absence of water-soluble solvent; in the presence of (B) 1 mL acetonitrile; (C) 3 mL acetonitrile; (D) 5 mL acetonitrile; (E) 5 mL ethanol; (F) 5 mL acetonitrile and 1 mL ethanol. System F produced the highest pesticide recoveries but the lowest fat extraction, thus eliminating the necessity for liquid-liquid partitioning and minimizing Florisil column cleanup. Pesticide recoveries throughout the procedure were 94– 103%. It was noticed, however, that the fat in high fat-containing raw milk is more readily extracted than that in commercial milk. Although a number of rapid methods
Identification of Canned Salmon Species by Scale Characteristics
Authors: Newton Richard T 
Published: February 2020

Abstract
A modified method and key for the identification of canned salmon species have been subjected to an additional collaborative study. Of 54 samples examined, 11 collaborators accurately identified 10 of 10 samples (100%) of sockeye, 11 of 11 samples (100%) of chum, 11 of 11 samples (100%) of pink, 11 of 11 samples (100%) of coho, and 11 of 11 samples (100%) of chinook. Nine of 11 collaborators were able to find in all samples usable scales with intact clear areas for mounting and identification. Two of the 11 had a minor problem. The improved, modified method and key have been adopted as official first action for the identification of the sockeye, chum, pink, coho, and chinook salmon species to replace method 18.089.
Gas-Liquid Chromatography of Bolstar Formulations
Authors: Boyd Willard G 
Published: February 2020

Abstract
A simple and rapid gas-liquiJ chromatographic method for assaying Bolstar formulations is described. Flame ionization detection, a column packed with SE-30/OV-210 on Gas-Chrom Q, and on-column injection are specified. Tetracosane internal standard in benzene is added to the weighed sample, and integratorarea ratios are used for quantitative measurement. The integrator response ratio of Bolstar area to tetracosane internal standard area, plotted against Bolstar concentration, is linear over a 2.85–7.78 mg/mL range. A technical material, a synthetic formulation, and 4 commercial formulations of Bolstar were assayed with good precision. Three assays of technical material against 3 standard weighings gave a coefficient of variation of 0.479%. Eight assays of a synthetic sample formulation, containing 63.86 theoretical per cent Bolstar, yield an average of 63.81% Bolstar with a coefficient of variation of 0.213%. Two assays each of 4 commercial Bolstar formulations gave an average coefficient of variation of 0.280%. Statistical analysis of 12 integrator response ratios, standard area to internal standard area, for 1 set of analyses gave a coefficient of variation of 0.322%.
Flameless Atomic Absorption Spectrophotometric Determination of Vendex, an Organic Tin Miticide, in Apples, Oranges, and Tea Leaves
Authors: Sano Mitsuaki , Furukawa Masako , Kourai Miyako , Tomita Isao 
Published: February 2020

Abstract
A method is described for the determination of an organic tin insecticide, Vendex or hexakis(2-methyl-2-phenylpropyl)distannoxane (HMPD). Tin compounds are extracted from the sample homogenate with ethyl ether containing 1% acetic acid. HMPD and its degradation products are separated through a silica gel column, and analyzed by an atomic absorption spectrophotometer coupled with a heated graphite atomizer. By this technique, as little as 5 ng HMPD and its degradation products can be determined with an average recovery of 67–96%.