bluuebunny/crossref_metadata_2025_split huggingface dataset:
Routine Estimation of Captan on Individual Sorghum Seeds
Authors: Simon Paul W , Kulik Martin M 
Published: February 2020

Abstract
A colorimetric method to delect captan was modified to permit rapid estimation of this fungicide on individual sorghum seeds. The procedure involves extraction of captan with benzene, removal of interfering dyes with Florisil, reaction with a resorcinol solution, and determination of color intensity with a colorimeter. One hundred seeds from each of 11 commercially treated samples were tested. The seeds numbered from 116,000 to 161,000/ lb. The average amount per sample of captan removed from seeds varied from 10.6 to 28.9 μg/seed and from 0.307 to 1.032 μg/mg seed weight. The theoretical amount of captan should have been 0.975 to 1.400 μg/mg seed weight, according to the container labels. The results indicate the need for closer control of seed treatment and for better definition of amounts of treatment required for adequate seed protection. The method presented now makes it feasible for seed testing laboratories to routinely determine amounts of captan on individual seeds. One technician could probably analyze up to 600 seeds daily, using equipment of larger capacity than the prototypes described in this paper.
Removal of Sulfur in Environmental Samples Prior to Gas Chromatographic Analysis for Pesticide Residues
Authors: Schutzmann R L , Woodham D W , Collier C W 
Published: February 2020

Abstract
Extracts of soil, water, and sediment often contain large amounts of elemental sulfur. This sulfur causes considerable interference in the GLC analysis of early eluting compounds by electron capture or flame photometric detection systems. A method is described whereby sulfur is removed by refluxing with a copper-aluminum alloy. Using a sample volume of 1 ml, up to 50 ppm elemental sulfur can be removed. Recovery of chlorinated pesticides from desulfurized extracts is &gt;80%. Parathion and malathion gave recoveries of approximately 50%.
Gas-Liquid Chromatography of Morestan Residues in Plants
Authors: Tjan G H , Konter Th 
Published: February 2020

Abstract
Two methods are described for the analysis of Morestan residues in plants. The first method is based on an acetonitrile cleanup, similar to the method of Mills et al.; the second involves a simple extraction with benzene. The extract solutions can be injected directly into a gas chromatograph without further cleanup. A capillary column at 200°C, packed with 5% QF-1 or DC-200 on Chromosorb W (AW), and an electron capture detector are used. Results of these studies indicate that the acetonitrile method and the rapid benzene method are applicable for the analysis of Morestan residues at a level of 0.1 ppm. Recoveries of 92-99% were obtained from 4 fruits and vegetables fortified with 0.1-0.5 ppm Morestan.
A Compact Extraction Apparatus for Use with the Semimicro Method for Determining Total Lipids in Fish Meal
Authors: Miller Harry , Knobl George M 
Published: February 2020

Abstract
A compact glass extraction apparatus has been designed for use with the semimicro chloroform-methanol extraction method for determining lipids in fish meal. No further handling is required after placing the sample in the extractor; this eliminates manipulative errors and makes the procedure more efficient. Results obtained with the use of this extractor agreed favorably with those from the semimicro method in which a blender was used and with results from AOAC 7.052. It is recommended that the method be studied collaboratively.
Determination of Saccharin in Biological Materials by Gas-Liquid Chromatography
Authors: Daun Robert J 
Published: February 2020

Abstract
A method is described for the quantitative determination of saccharin in urine, feces, blood, and animal tissues. The saccharin is extracted with diethyl ether and methylated with methyl iodide to provide a volatile derivative for gas-liquid chromatography. Higher levels, as found in urine and feces, are determined with a flame ionization detector and lower levels, as in blood and tissues, are analyzed with an electron capture detector after a thin layer chromatographic separation.
Automated Determination of Thiamine (Vitamin B1) in Pharmaceutical Preparations
Authors: Pelletier Omer , Brassard RenÉ 
Published: February 2020

Abstract
The chemical principles used for the determination of thiamine in pharmaceutical preparations by the official USP and AOAC methods were adapted to an automated flowthrough analyzer. The system could analyze 20 samples (including blanks) per hour. Thiamine extracts from 12 different multivitamin preparations were analyzed by one analyst on 5 different days by the automated method and the AOAC method. Both methods yielded comparable values for 10 of the preparations. The thiamine content of 2 preparations containing liver extract was found to be about 9% higher by the automated method than by the AOAC method. Further analysis of other samples of these 2 preparations containing liver extract showed that chromatography on Decalso did not change the results obtained by the automated method, but raised the results obtained by the manual method to a level comparable to the automated method. The AOAC method showed a tendency for a slightly higher reproducibility of assays.
Chemical Analysis of Vitamin D in Concentrates and Its Problems. XII. Analysis of Fat-Soluble Vitamins
Authors: Mulder F J , De Vries E J , Borsje B 
Published: February 2020

Abstract
Details of analytical procedures are given for the analysis of vitamin D concentrates, such as resins, powders, and solutions, all without vitamin A. For the analysis a choice had to be made between the potential vitamin D content (the sum of calciferol (D) and precalciferol (P)) and the actual vitamin D content (calciferol only) in partly isomerized solutions. The biological vitamin D assays can only give the potential vitamin D content when both sample and reference standard solutions are equilibrated simultaneously to the same P ⇋ D ratio. Therefore the biological vitamin D unit should be based on the potential vitamin D content. An important point in the chemical assay of vitamin D in concentrates is the prevention of the oxidation of fat-soluble phenolic antioxidants during saponification. These oxidation products of antioxidants inhibit the color reaction. The colorimetric determination becomes more specific after inactivation of tachysterol by the addition of maleic anhydride. A collaborative test was carried out in 3 laboratories with an oil containing 3 different concentrations of vitamin D. The results of this test have verified the correctness of the analytical procedures.
Gas-Liquid Chromatographic Identification and Determination of Alkanolamines. I. Application to Aerosol Hair Sprays
Authors: Champion Margaree H , Jones John H 
Published: February 2020

Abstract
Alkanolamines, in the absence of water, are converted to the amide ester or triacetate with acetic anhydride-pyridine mixture. The amide ester or triacetate of the alkanolamine is determined by GLC on a column containing diethylene glycol succinate on Chromosorb G. Procedures for determining alkanolamines in various hair sprays are described; recoveries by the proposed procedure were satisfactory. The method developed was applied to the following 4 alkanolamines: 2-amino-2-methyl-1-propanol, 2-amino-2-methyl-1,3-propanediol, 2-amino-2-ethyl-1,3-propanediol, and triisopropanolamine.
Fluorometric Determination of Estradiol Valerate in Sesame Oil or Ethyl Oleate Injectables
Authors: James Theron 
Published: February 2020

Abstract
A fluorometric procedure has been developed for the quantitative determination of estradiol valerate in sesame oil or ethyl oleate. An n-heptane solution of the steroid is purified, using a nitromethane partition column. The purified estradiol valerate is dissolved in alcohol and determined fluorometrically. The method is applicable to a variety of commercial preparations, including estradiol valerate-testosterone enanthate combinations. A total of 14 determinations on 5 different synthetic preparations gave an average recovery of 97.2%. It is recommended that this method be subjected to a collaborative study.
Screening Test for Fluoroacetate in Baits and Biological Samples
Authors: Stahr H M , Clardy Darrell O , Buck William B 
Published: February 2020

Abstract
A simple screening test, based on reaction of the fluoride ion with the ion-selective fluoride electrode, has been developed for fluoroacetate in baits and biological samples. Positive results have been obtained in diagnostic cases. The method is not specific for fluoroacetate, but other fluoride-containing compounds are not likely to be present in the extract. Positive responses to the test should be confirmed as fluoroacetate by another method, such as the official AOAC method or by gas chromatography-mass spectrometry.
Detection of Adulteration of Fruit Juice. I. Characterization of Israel Lemon Juice
Authors: Lifshitz A , Stepak Y 
Published: February 2020

Abstract
A survey of some of the constituents of Israel lemon juice was conducted during the last 4 years. Fifty-eight samples of natural juice, obtained from various sources, were tested for a number of analytical parameters, including a detailed free amino acids analysis. The changes of total soluble solids and acidity as the season progressed were traced. The data were given some statistical treatment.
Detection of Adulteration of Fruit Juice. II. Comparison of Statistical Methods
Authors: Lifshitz A , Stepak Y , Brown M B 
Published: February 2020

Abstract
Following a survey of lemon juice composition, the analytical data are given 2 different statistical treatments. On comparing these treatments, it is found that the specific test based on classical chi-square distribution is more powerful than that based on regression analysis. The analysis of free amino acids provides a method for the detection of adulteration of lemon juice, which is both efficient and difficult to circumvent.
Relative Standard Deviations in Determinations of Amino Acids
Authors: Kwolek W F , CAVINS J F 
Published: February 2020

Abstract
Eighteen references were selected for computation of the relative standard deviation in determinations of amino acids. Cysteine, tryptophan, tyrosine, and methionine were associated with higher relative standard deviations than other amino acids. A mean relative standard deviation of about 8%, ranging from 5.9 to 14.1% depending on the amino acid, was observed between samples independently hydrolyzed. The relative standard deviation between aliquots of the same hydrolysate was 2.7%. Differences in amino acids of 10 to 12% are statistically significant when 2 means, each based on 2 hydrolyses, are compared.
Improvement of the AOAC Kilogram Sample Method for the Isolation of Aflatoxin B1 for Chemical and Biological Confirmation
Authors: Stack Michael , Rodricks J V 
Published: February 2020

Abstract
The official AOAC 1 kg method of isolating aflatoxin B1 for confirmative testing has been improved. An acid alumina column substituted for the 10 g silica gel column eliminates the oily residue which interferes with preparative TLC. Time is saved by processing only enough extract to yield the required amount of aflatoxin. Application of the procedure to aflatoxin-contaminated peanut butter, Brazil nuts, cottonseed meal, and corn resulted in aflatoxin B1 extracts which showed only one spot on TLC plates and gave positive derivative and Bacillus megaterium tests. Aflatoxin-free sample extracts gave negative B. megaterium tests.
Gas Chromatographic Determination of Monitor (O,S-Dimethyl Phosphoramidothioate) Residues in Crops
Authors: Leary J B 
Published: February 2020

Abstract
A gas chromatographic method is described for determining Monitor (0,S-dimethyl phosphoramidothioate) in a variety of crops. After extraction of the sample with ethyl acetate, the solvent is evaporated and an ether solution of the residue is passed through a silica gel column to remove interferences. Monitor is then eluted from the column with acetone and measured by gas chromatography, using a cesium bromide thermionic detector. The majority of standard recovery values ranged between 90 and 100% when samples were fortified at 0.05 to 0.1 ppm.
Improved Method for Determining Benomyl Residues
Authors: Pease H L , Holt R F 
Published: February 2020

Abstract
A fluorometric and colorimetric procedure for determining benomyl residues previously reported has been modified to make it less time-consuming and to now permit analyses of substrates, i.e., citrus, that could not previously be analyzed by the fluorometric method. The sensitivity of the method remains the same, about 0.1 ppm. An alternative procedure to the colorimetric method previously recommended for differentiating between benomyl and other fungicidal benzimidazoles is also described. This alternative procedure is based on fluorometric measurement from both acid and basic media.
Colorimetric Method for the Estimation of Alkaloids in Lobelia and Its Pharmaceutical Preparations
Authors: Karawya M S , Abdel-Wahab S M , Zaki A Y 
Published: February 2020

Abstract
The total alkaloids of lobelia herb and its tincture were estimated colorimetrically after reaction with formaldehyde-sulfuric acid reagent; the results were found to be comparable with those of the 1963 Egyptian Pharmacopoeia method. The alkaloids lobeline, lobelanine, and lobelanidine were estimated individually in the herb and tincture after using the TLC-colorimetric method. The method was found to be sensitive and applicable to pharmaceutical preparations such as lobeline sulfate tablets and lobeline hydrochloride ampuls.
Separation of Three Chlorodibenzo-p-dioxins from Some Polychlorinated Biphenyls by Chromatography on an Aluminum Oxide Column
Authors: Porter Mildred L , Burke Jerry A 
Published: February 2020

Abstract
The separation of 2,3-dichlorodibenzo-p-dioxin, 2,3,7-trichlorodibenzo-p-dioxin, and 2,3,7,8-telrachlorodibenzo-p-dioxin from polychlorinated biphenyls by column chromatography on aluminum oxide is described. Polychlorinated biphenyls were eluted first with 1% methylene chloride-hexane and chlorodioxins were then eluted with 20% methylene chloride-hexane. Recoveries of both polychlorinated biphenyls and chlorodioxins approximated 100%.
Automated Photometric Microbiological Assay for Monensin in Poultry Rations
Authors: Kavanagh F W , Willis Mary 
Published: February 2020

Abstract
A new photometric microbiological assay is described for the coccidiostat monensin in poultry feeds and premixes. The crucial steps in the assay are performed by an automated system. Samples are extracted with acetone and diluted in 50% aqueous acetone to appropriate levels for assay by Streptococcus faecalis ATCC 8043. A special pH 5.2 medium, low in potassium, and polysorbate 80 are used to obtain maximum sensitivity without interference. The range of applicability of the standard curve is 0.10–0.4 μg monensin/ml sample. The assay is free from bias. A relative standard deviation of 1.7% was obtained when 10 feed samples were extracted and assayed 5 times each.
Collaborative Study of Automated Determination of Phosphorus in Meat Products
Authors: Gantenbein Walter M 
Published: February 2020

Abstract
A collaborative study has been conducted on a modification of a previously reported automated method for phosphorus in meat products. Samples were dissolved in 1 + 1 sulfuric acid, cooled to room temperature, and presented to an AutoAnalyzer system. Digestion, dilution, and colorimetric measurement of phosphorus content were performed automatically. Six collaborators participated in the study, analyzing 8 different samples in duplicate. Results of the study were good, with an average range of 0.012% P, average standard deviation of ±0.0047, and average coefficient of variation of 2.32%. The method is recommended for adoption as official first action.
Column Partition Chromatographic Assay for Codeine in Tablets Containing APC
Authors: Siegmund Emil G 
Published: February 2020

Abstract
Codeine is separated from aspirin, phenacetin, and caffeine (APC) on a Celite pH 5.1 buffer column. APC is eluted with ether and determined by AOAC method 36.193–36.198. Codeine is eluted as an ion pair with di-(2- ethylhexyl) phosphoric acid, extracted with 0.LN H2SO4, and determined by UV spectrophotometry. Five commercial samples and 2 synthetic mixtures were analyzed by 9 collaborators for codeine. Recoveries averaged 99.4 ± 1 . 6% and 103±4.0% for the synthetic mixtures containing 16.3 and 1.0 mg/tablet, respectively. The means and standard deviations for commercial tablets were 58.7 ±0.81 mg, 30.4±0.46 mg, 14.5±0.44 mg, 7.54±0.11 mg, and 0.96 ±0.03 mg. The method has been successfully used to analyze all 4 components in 11 commercial samples. The method for codeine is recommended for adoption as official first action.
Column Chromatographic Assay for Sodium Butabarbital in Tablets
Authors: Kaplan Gilbert B , Levine Joseph 
Published: February 2020

Abstract
A column partition chromatographic assay for sodium butabarbital tablets is described. The method was collaboratively studied with a composite of commercial tablets and a preparation of known composition as samples. The average recovery for both samples was 99.3%; the standard deviations were 1.4 and 1.1%, respectively. It is recommended that the method be adopted as official first action.
Collaborative Study of Assay for Benzthiazide and Hydrochlorothiazide in Pharmaceuticals
Authors: Fazzari F Raymond 
Published: February 2020

Abstract
A method for the determination of benzthiazide and hydrochlorothiazide in pharmaceuticals was collaboratively studied by 10 analysts. The method is a previously published column partition chromatographic technique with a spectrophotometric determination. The average per cent recovered and standard deviation for preparations of benzthiazide and hydrochlorothiazide were, respectively, 99.5±1.35 and 99.6±1.22. It is recommended that the method be adopted as official first action for benzthiazide, hydrochlorothiazide, and hydroflumethiazide
Gas-Liquid Chromatographic Determination of Paraldehyde in Paraldehyde Elixir
Authors: Lampkin William T 
Published: February 2020

Abstract
A collaborative study was conducted on a GLC method for determining paraldehyde in pharmaceutical preparations of paraldehyde elixirs. Eleven collaborating laboratories analyzed 2 unknown paraldehyde solutions and a solution of known paraldehyde concentration. Recoveries of 15–25% paraldehyde solutions averaged 98.5% with a coefficient of variation of about 2%. The method consists of diluting a sample aliquot to a definite volume and determining the paraldehyde content by GLC, using a flame ionization detector and a 6’ × 4 mm coiled glass column packed with 80–100 mesh Diatoport S coated with 2% HIEFF-8BP (cyclohexane dimethanol succinate) plus 20% Carbowax 20M. The internal standard technique was used for calculation. It is recommended that the method be adopted as official first action.
Automated Fluorometric Analysis of Reserpine and Syrosingopine Tablets, Using a Vanadium Pentoxide Reagent
Authors: Urbányi Tibor , Stober Henry 
Published: February 2020

Abstract
Semiautomated methods suitable for the determination of reserpine and related compounds in tablet formulations have been reported. The basis of these methods of determination is the classical nitrite procedure. The need of a more practical, completely automated system with less manipulation resulted in the development of a fluorometric method, using vanadium pentoxide as a reagent. This method is rapid, precise, and sensitive enough for formulations containing as little as 0.1 mg reserpine or similar compounds per unit dosage. The parameters influencing the sensitivity, precision, and speed of the new fluorometric determination are described in detail.
Determination of Dienestrol in Pharmaceuticals
Authors: Graham Joseph H , Banes Daniel , Proctor Joseph B 
Published: February 2020

Abstract
A highly specific, rapid, and sensitive assay procedure for dienestrol in pharmaceuticals has been developed. Dienestrol is separated from excipient matter and other drugs present in the dosage form by column chromatography and determined spectrophotometrically as a substituted indene, formed by acidinduced isomerization of dienestrol. The procedure is directly applicable to creams and individual tablets.
Chemical Composition of Mexican Pineapple
Authors: Boland Frederick E , Blomquist Victor H , Estrin Ben 
Published: February 2020

Abstract
Authentic data are presented on the chemical composition of Mexican pineapple. Samples were analyzed for total soluble solids, ash, K20, P2O5, invert sugar, sucrose, protein, acidity (as anhydrous citric acid), insoluble solids, Na20, and amino acids. The data are presented for 18 samples (10 canned and 9 fresh).
Turbidimetric Evaluation of Bacterial Culture Resistance in Disinfectant Testing
Authors: Chen John H S , Ortenzio L F 
Published: February 2020

Abstract
A simple turbidimetric method has been developed for determining the degree of phenol resistance of cultures used for disinfectant testing. Net transmission values are used to assess t h e degree of resistance; these are based on t h e measurement of the total amount of light scattered by the bacterial growth i n the AOAC broth medium without interfering turbidity of the dissolved ingredients. A decrease in the net transmission value corresponds to a decrease in phenol resistance; the converse is also true . The transmission values obtained in a 10 month study of a total of 77 weekly r and om samples of AOAC nutrient broth media blanks showed no substantial differences among the broth media tested by the turbidimetric method. Net transmission values were obtained for 71 broth cultures of Salmonella choleraesuis, 74 of Staphylococcus aureus, and 78 of Pseudomonas aeruginosa having the same required resistance against phenol. These values, which fell within a wider range than would be expected, are given. The effect of the number of 10-carrier-soakings on the net transmission value and equivalent phenol resistance of the cultures was determined for 60 broth cultures of the 3 test organisms named above. Soaking wet cylinder carriers in a given volume of test cultures used for the AOAC use-dilution test directly reduced the net transmission value and equivalently decreased the phenol resistance of the cultures. The turbidimetric method has proven experimentally satisfactory i n several hundred determinations and in selecting test cultures of uniform quality for disinfectant testing.
Simplified Method for the Determination of Propionates in Bread: Isolation by Micro diffusion
Authors: Karasz A B , Hallenbeck W 
Published: February 2020

Abstract
In the method presented, propionic acid is isolated from bread by microdiffusion at an elevated temperature in preparation for determination by gas-liquid chromatography. This isolation procedure is simple, utilizes inexpensive equipment, and permits the simultaneous processing of a large number of samplef. Results obtained by microdiffusion agree closely with those obtained by steam distillation according to AOAC 14.089. After isolation by either microdiffusion or steam distillation, propionic acid in all samples was determined by gas-liquid chromatography as described in 18.038 rather than partition column chromatography as described in 14.090-14.091. An average of 98% of the propionic acid found by using steam distillation was found by using the microdiffusion technique.
Structure of Ethylene Thiuram Monosulfide
Authors: Benson W R , Ross R D , Chen Jo-Yun T , Barron R P , Mastbrook D 
Published: February 2020

Abstract
A new structure is proposed for ethylene thiuram monosulfide based primarily on mass, Raman, and nuclear magnetic resonance spectral data. Data in the older literature, for the most part, are consistent with both the old and new structures; however, new data are consistent only with the new structure.