bluuebunny/crossref_metadata_2025_split huggingface dataset:
Precision Parameters of Methods of Analysis Required
for Nutrition Labeling. Part II. Macro Elements—Calcium,
Magnesium, Phosphorus, Potassium, Sodium, and Sulfur
Authors: Horwitz William , Albert Richard , Deutsch Mike J , Thompson Neville J 
Published: February 2020

Abstract
A previous paper reviewed the precision of analyses for the major macronutrients—fat, protein, and carbohydrates— as well as moisture/solids, ash, and "fiber." A similar review is now presented for the macro inorganic nutrients—calcium, magnesium, phosphorus, potassium, sodium, and sulfur. The precision parameters among laboratories (standard deviations, S; relative standard deviations, RSD; and repeatability, r, and reproducibility, R, values) are not characterized by any conventional distribution. The typical precision of the methods of analysis for these elements In food can be expressed solely as a logarithmic function of concentration, Independent of analyte, matrix, and method. The average RSDR value from each collaborative assay found in the literature Is used as the numerator in a ratio containing, as the denominator, the value calculated from the logarithmic function: RSDR(%) = 2( 1 -0.5 log C) where C Is the concentration as a decimal fraction. If this ratio, designated as HORRAT, Is above 2, the method Is probably unacceptable with respect to precision. About 20% of the 465 interlaboratory data sets studied for this paper show an RSDR exceeding the acceptable limit, with an overall average HORRAT of 1.2 at C ranging from about 20 x 10-6(20 ppm) to about 10-1 (10%). The variability, although high, may be acceptable for the purpose of nutrition labeling.
Analytical Strategy for the Regulatory Control
of Residues of Chloramphenicol in Meat: Preliminary Studies
in Milk
Authors: Keukens H J , Aerts M M L , Traag W A , Nouws J F M , De Ruig W G , Beek W M J , Den Hartog J M P 
Published: February 2020

Abstract
An analytical strategy Is described for the regulatory control of residues of the veterinary drug chloramphenicol (CAP) In meat. Screening is performed directly in meat by a simple immunochemical card test with a limit of detection of about 2 μg/kg. Statistical evaluation of a collaborative study involving 13 laboratories showed that at CAP concentrations exceeding 8 μg/kg, no false negatives are found (N = 554). In positive samples, CAP Is quantltated with a routinely applicable, collaboratively tested column liquid chromatographic method with a limit of detection of about 1 μg/kg. At concentrations exceeding 10 μg/kg, the Identity of CAP Is established by Its UV spectrum obtained by using diode-array UV/VIS detection. A further confirmation can be obtained by the combination of gas chromatography/ mass selective detection In the electron Impact mode. Using 2 diagnostic Ions (m/z 225 and 208), the limit of identification Is about 5 μg/kg. The combination of the different analytical principles ensures reliable quantitation and Identification of CAP in positive samples, as established experimentally in Incurred samples and spiked samples (n &gt; 100), and theoretically by the estimation of the uncertainty factor. The proposed set-up makes a regulatory program possible in which screening can be performed In a simple laboratory environment, followed by quantitation and Identification under more sophisticated conditions. Preliminary experiments Indicate that the analytical strategy Is also applicable to the control of CAP in milk. Application of mass spectrometry with negative chemical ionization permits the confirmation of CAP concentrations as low as 0.2 μg/L.
Determination of Cloxacillin and Penicillin V in Milk
Using an Automated Liquid Chromatography Cleanup
Authors: Moats William A , Malisch Rainer 
Published: February 2020

Abstract
A number of screening tests will detect β-lactam antibiotics at levels of less than 10 ng/mL in milk. However, confirmatory procedures of comparable sensitivity are not available. A method using an automated liquid chromatography (LC) cleanup sensitive to 1 ng/mL was developed for penicillin V and cloxacillin. Milk was deproteinlzed with 2 volumes of acetonitrlle. Methylene chloride and hexane were added to the filtrate to separate the water layer containing the antibiotics. The filtrate could also be evaporated directly. The water layer was concentrated and loaded onto a polymeric LC column in 0.01 M pH 7 buffer with the aid of an autosampler. The penicillins were eluted with an acetonitrlle gradient from pH 7 buffer (100%, 0-3 mln) to pH 7 buffer-acetonltrlle (40 + 60,25 mln). Fractions containing each compound were collected and rechromatographed Isocratlcally on the same column type in 0.01 M H3P04-acetonltrlle (58 + 42 for cloxacillin; 62 + 38 for penicillin V). The cleanup can be fully automated. The approach is applicable to other penicillins, but suitable conditions for analysis of fractions for each compound must be developed. Recoveries for penicillin V were 88 ±2% at 1 ppm, 89 ±10% at 0.1 ppm, and 87 ±13% at 0.01 ppm. For cloxacillin, recoveries were 97 ±5% at 1 ppm, 90 ±4% at 0.1 ppm, and 89 ±8% at 0.01 ppm.
Extraction of Light Filth from Fish Paste and Sauce (Bagoong)
Not Containing Spice: Collaborative Study
Authors: Glaze Larry E 
Published: February 2020

Abstract
A collaborative study was conducted to validate a new method for the extraction of light filth from fish paste and sauce (Bagoong) not containing spice. A 225 g test portion is digested by boiling in a mixture of acid and emulsifying agents. Light filth is isolated by wet sieving on a No. 230 plain weave sieve with Tergitol, a deaeration boil in 40% isopropanol, and flotation with mineral oil and 40% isopropanol in a Wildman trap flask. Three spiking levels were used in the study for rat hairs and Insect fragments; 1 level was used for whole or equivalent insects. For rat hairs, recoveries at the low, medium, and high levels averaged 77,94, and 76%, respectively. Recoveries of Insect fragments for these levels averaged 92,88, and 93%, respectively; recoveries of whole or equivalent Insects averaged 85,70, and 80%, respectively. The method was adopted first action by AOAC International for the extraction of light filth from fish paste and sauce (Bagoong) not containing spice.
Production and Characterization of Antibodies Against Neosaxitoxin
Authors: Chu Fun S , Huang Xuan , Hall Sherwood 
Published: February 2020

Abstract
Antibody against neosaxitoxin (neo-STX) was obtained from rabbits after immunization with neo- STX conjugated to either keyhole limpet hemocyanln (KLH) or bovine serum albumin (BSA). An indirect enzyme-linked Immunosorbent assay (ELISA), In which either neo-STX-BSA or neo-STXKLH was coated to the mlcroplate, was used to monitor the antibody titer. Although high antibody titers were obtained from rabbits after immunization with both immunogens, only antibody obtained from rabbits immunized with neo-STX-KLH was useful for Immunoassay. Competitive indirect ELISA revealed that the antibodies obtained from rabbits Immunized with neo-STX-KLH are specific for neo-STX but also have good cross-reactivity with STX. The concentrations causing 50% inhibition binding of neo-STX-BSA to the anti-neo-KLH by neo-STX, STX, and decarbamoyl-STX (DC-STX) were 0.9,8.0, and 53.1 ng/mL, respectively. Saxitoxin conjugated to polylyslne (STX-PLL) was also used as the coating reagent In the indirect ELISA. The concentrations causing 50% inhibition binding of antl-neo-STX-KLH to STX-PLL coated on the mlcrotiter plate by neo-STX, STX, and DC-STX were 1.2,4.1, and 36.1 ng/mL, respectively. With this newly developed antibody, ELISA could be a very effective method for monitoring seafood for both neo-STX and STX.
Nonenzymatic-Gravimetric Determination of Total Dietary Fiber in Fruits and Vegetables
Authors: Li Betty W , Cardozo Maria S 
Published: February 2020

Abstract
Most gravimetric methods for total dietary fiber (TDF) determination require the complete removal of starch and the partial removal of protein with various combination of enzymes In buffers at different pH values and at temperatures much above ambient condition. A hydrolysis step Is crucial In dietary fiber analysis of samples, such as cereals and legumes, which contain appreciable amounts of starch. However, many vegetables and most fruits contain very little or no starch, and they are often eaten uncooked. It would be unnecessary to use high temperatures and enzymes on these types of samples. Initially, we found that hexane and dilute alcohol extractions of a few selected fruits and vegetables gave residue weights comparable to those after enzymatic treatments. We were able to show later that simply suspending the samples in delonized water for 90 mln at 37°C and then adding 95% ethanol also yields TDF values similar to those obtained from other published methods. Comparison data obtained by using variations of the AOAC/TDF method are presented for 10 fruits and vegetables.
Liquid Chromatographic Method for Determination of Glycerol in Wine and Grape Juice: Collaborative Study
Authors: Caputi Arthur , Christensen Eric , Biedenweg Nancy , Miller Susan 
Published: February 2020

Abstract
An Ion-exchange liquid chromatographic method for the determination of glycerol in wine, white grape juice, and pink grape juice was collaboratively studied by 8 laboratories. Eight wine types and 12 juice samples were provided to each collaborator. Using a strong cation column, blind duplicates and standards were analyzed by an external standard method. Separate statistical evaluations were run on wine, white grape juice, and pink grape juice data. The averages of the relative standard deviations for repeatability, excluding outlying results, were 1.25% for the wine samples, 7.32% for the white grape juice samples, and 8.63% for the pink grape juice samples. The averages of the relative standard deviations for reproducibility, excluding outlying results, were 2.79% for the wine samples, 16.97% for the white grape juice samples, and 19.10% for the pink grape juice samples. The method has been adopted first action by AOAC International.
Total Diet Study of Lead and Cadmium in Food Composites: Preliminary Investigations
Authors: Dabeka Robert W , Mckenzie Arthur D 
Published: February 2020

Abstract
In a trial for a comprehensive total diet study, 105 food composites were prepared in the summer of 1985, and another 105 composites in the late fall of 1985. Lead and cadmium were determined In all composites. The mean, median, and range of lead concentrations in the samples were 29.9, 14.7, and 1.42-407 ng/g, respectively. The estimated dietary Ingestion of lead by the average adult Canadian was 36.4 μg/day. The mean, median, and range of cadmium concentrations were 13.7, 5.4, and &lt;0.07- 297 ng/g. Dietary ingestion of cadmium by adults averaged 14.5 μg/day. Sample planning and contamination control for trace element determinations of the study are discussed.
1H NMR Spectroscopic Method with Chiral Eu(III) Shift Reagent for the Determination of the Enantiomeric Composition of Naproxen
Authors: Hanna George M , Lau-Cam Cesar A 
Published: February 2020

Abstract
A simple method based on the use of 1H NMR spectroscopy with chiral Eu(lll) shift reagent is described for the determination of (S)-(+)- and (R)-(-)-naproxen In the presence of each other. To enhance the coordinating affinity of the substrate for the lanthanide Ion, the sample was first derivatized to a mixture of methyl esters, which in the presence of Eu(hfc)3 formed short-lived diastereomeric complexes with sufficient nonequivalency In the 1H NMR spectrum. Optimum complexing conditions corresponded to concentrations of substrate and Eu(hfc)3 of 0.1 M each in CDCI3. In this matter, the enantiomeric ester-methyl protons and α-methyl protons yielded well-resolved resonance signals of utility in the measurement of enantiomeric compositions. Recovery studies demonstrated that the proposed method Is quantitative.
Liquid Chromatographic and Spectral Analysis of the Stereoisomers of Dimethylaminorex
Authors: Noggle F Taylor , Clark C Randall , Derutter Jack 
Published: February 2020

Abstract
The Individual enantiomers of cls- and trans-3,4-dlmethylamlnorex were prepared by treating ephedrines or pseudoephedrines with cyanogen bromide. These compounds represent potential designer drug modifications of aminorex and 4- methylaminorex, which have appeared recently in the clandestine drug market. The UV spectra for these compounds are typical of phenethylamlnetype compounds, and FTIR spectra allow for differentiation of cls- and trans-lsomers. The mass spectra for the dimethylamlnorex stereoisomers show characteristic fragments at m/z 57,118, and 190. The cls- and trans-lsomers were separated In a reversed-phase liquid chromatographic system on a C18 stationary phase, with the cls-lsomer displaying the higher capacity factor.
Capillary Column Gas Chromatographic Method for Analysis of Encapsulated Fish Oils and Fish Oil Ethyl Esters: Collaborative Study
Authors: Joseph Jeanne D , Ackman Robert G 
Published: February 2020

Abstract
A gas chromatographic (GC) method using a capillary column for analysis of encapsulated fish oils and ethyl esters was studied collaboratively in 21 laboratories. Each collaborator analyzed 6 soft-gelatin encapsulated samples; 5 were trlacylglycerol oils (one was a blind duplicate), and one was an ethyl ester concentrate of omega-3 (n-3) polyunsaturates. Constituent fatty acids of the oils were converted to methyl esters by base-catalyzed transesterlflcatlon of the oils; any free acids in the oils were esterlfied by subsequent reaction with BF3/CH3OH. The ethyl ester concentrate required no further derlvatlzation. Results were reported as area percentages of 24 analytes of nutritional or biochemical interest. In addition, weights (mg/g sample) of EPA (all-c/s-5,8,11,14,17-elcosapentaenolc acid or 20:5n-3) and DHA (all-c/s- 4,7,10,13,16,19-docosahexaenoic acid or 22:6n-3) were determined through the use of the internal standards, respectively, methyl tricosanoate (23:0) and ethyl 23:0, for the methyl and ethyl esters. The only instrumentation specifically required was a flexible fused silica capillary GC column coated with a bonded polyglycol such as Carbowax-20M, an oxygen scrubber Installed In the carrier gas supply line, and a flame Ionization detector (FID). Most of the collaborators experienced little difficulty In applying the method, and, of 2526 values reported, only 4.3% were identified as outlier values. The reproducibility relative standard deviations (RSDR) compared favorably in most instances with, or were substantially better than, those of 2 earlier collaborative studies of fish oils. Because the variances were homogeneous, standard deviations and relative standard deviations determined on the area percent analyses of the blind duplicate oils were pooled to give the following mean values: sr = 0.15, RSDr = 4.88%, sR = 0.41, and RSDR = 12.91%. Analytes that rarely occur at greater than 0.5% In marine oils (22:0,22:4n-6,22:5n-6,24:0, and 24:1) were not Included in these calculations. The method was adopted first action by AOAC International as an American Oil Chemists' Society (AOCS)-AOAC method.
Rapid and Simple Coulometric Measurements of Peroxide Value in Edible Oils and Fats
Authors: Oishi Mitsuo , Onishi Kazuo , Nishijima Motohiro , Nakagomi Kazuya , Nakazawa Hiroyuki , Uchiyama Shunichi , Suzuki Shunichi 
Published: February 2020

Abstract
A rapid coulometric method was developed for the measurement of peroxide value In edible oils and fats. The sample size and reagents volumes In this method are considerably less than those in the American Oil Chemists' Society method. Iodine produced by the reaction of the Iodide Ion and peroxide In the sample Is electrochemlcally reduced at the carbon-felt electrode more rapidly than it is with lodometric titration. The present method Is successfully applied to the measurements of edible oils and fats, and the coulometric results obtained are consistent with those obtained by iodometry.
Analysis of 5-Vinyl-l,3-Oxazolidine-2-Thione by Liquid Chromatography
Authors: Quinsac Alain , Ribaillier Daniel , Rollin Patrick , Dreux Michel 
Published: February 2020

Abstract
5-Vlnyl-1,3-oxazolldlne-2-thlone (5-VOT) Is a goltrlgenlc compound released by enzymatic degradation of progoltrln, the major glucoslnolate occurring In rapeseed meal. A liquid chromatographic (LC) method for determination of 5-VOT in a biological environment Is presented. Complete extraction of 5-VOT has been carried out by complexatlon with phenyl mercury acetate under cyclohexanlc conditions, and then by decomplexation using an aqueous sodium thlosulfate solution. These reactions displace 5-VOT from an aqueous to an organic medium, and then back again to the aqueous condition, thus assuring high selectivity of the extraction. Precise quantitation of 5-VOT Is completed in 10 mln by reversed-phase liquid chromatography using an isocratic elutlon with UV detection and a specially made synthetic Internal standard. Concentration steps by solid-phase chromatography and evaporation can be introduced In the analytic procedure to lower the detection limit of 5-VOT in the sample used from 100 to 0.5 ppb. Using sow milk samples, the method was tested by small measured additions of 5-VOT. The recovery rate of the product was very good (&gt;97%). Different phases used to achieve a sensitive, rapid, and precise method are described.
Development and Validation of a Multiresidue Method for β-Agonists in Biological Samples and Animal Feed
Authors: Ginkel Leendert A van , Stephany Rainer W , Rossum Hennie J Van 
Published: February 2020

Abstract
An analytical strategy for the detection of β-agonlsts containing either an N-tert-butyl or N-sopropyl group is described. Extract purification Is based on Immunoaffinity chromatography; final detection, identification, and determination are by gas chromatography/mass spectrometry. To prepare the immunoaffinity chromatography materials, poly-valent antibodies are raised against clenbuterol and cimaterol. The immunoglobulin G fractions of the corresponding rabbit antlsera are isolated and coupled onto an activated Sepharose™ matrix. The prepared columns gave quantitative recovery for a large number of structurally related β-agonists at the 200 ng level. To quantitate and control falsenegative results, Isotope-labeled internal standards are used. For animal feed and bovine urine, analytical recoveries were close to 100% for all compounds except salbutamol (56 ± 5%). Recoveries from liver were in the range of 60-70% (salbutamol, 40-50%). Limits of detection, based on the corresponding most abundant Ion, were In the range of 0.05-0.2 μg/kg or μg/L. Limits for Identification, based on the simultaneous detection of 4 diagnostic ions, were In the range of 1-2 μg/kg or μg/L. Repeatability and within-laboratory reproducibility, expressed as percent relative standard deviation, were all well below 15%, which fulfills the EC criteria for reference methods. The multiresidue method Is an efficient, cost-effective way to determine Illegal growth-promoting N-terf-butyl and N-Isopropyl phenylethanolamlnes.
Detection of Beet Sugar Adulteration of Orange Juice by Liquid Chromatography/Pulsed Amperometric Detection with Column Switching
Authors: White Richard D , Cancalon P E 
Published: February 2020

Abstract
A recently reported method for the quantitation of extraneous beet sugar In orange juice is based on the monitoring of unique oligosaccharides present in beet medium invert sugar (BMIS). Modifications are reported here that expedite the method and render it better suited for monitoring a large number of samples on a routine basis. A switching valve that allows the simple sugars to go to waste after the first column prevents overloading of the analytical column and detector. Furthermore, the retention and column re-equilibration times were significantly reduced. Results of spiking studies of BMIS In orange juice are reported. The estimated limit of detection is 5% BMIS, with a coefficient of variation of 0.1 %.
Liquid Chromatographic Method for Determination of Methamidophos in Technical Products and Pesticide Formulations: CIPAC Collaborative Study
Authors: Hanks Alan R 
Published: February 2020

Abstract
A reversed-phase liquid chromatographic (LC) method for the determination of technical methamidophos and 5 different formulated products was collaboratively studied in 18 laboratories. Samples were dissolved in water, separated by LC, and detected at 210 nm. Quantitation was done by peak area measurements. Relative standard deviations for repeatability and reproducibility ranged from 0.35 to 0.80 and from 1.14 to 1.60, respectively. The method has been approved first action by AOAC International as a CIPAC-AOAC method.
Comparison of Three Methods for Calculating Protein Content in Developing Apple Flower Buds
Authors: Khanizadeh Shahrokh , Buszard Deborah , Zarkadas Constantinos G 
Published: February 2020

Abstract
Three methods (Kjeldahl, sulfuric acid-hydrogen peroxide, and summation of amino acid content) for determining and calculating the protein content of apple flower buds were compared. Quantitation of protein content based on summation of amino acids appears to be the most accurate method. A new nitrogen:protein conversion factor (5.51) was calculated based on total amino acid analysis. This new conversion factor could replace the conventional 6.25 factor for estimating total protein content of apple flower bud by the Kjeldahl method. However, Kjeldahl is not an accurate method for estimating protein content in apple flower bud tissue, regardless of the conversion factor, and probably would not be a good method for estimation of protein in other plant species.
Training Modules To Develop Analytical Proficiency for Pharmaceutical Chemists
Authors: Kenyon, Allen S , Kirchhoefer Ross D , Layloff Thomas P 
Published: February 2020

Abstract
As a part of a training program for new personnel in pharmaceutical analysis and for visiting scientists from other government laboratories, the Division of Drug Analysis (DDA) developed training modules to raise the job performance of incoming college students, technical aides, and newly hired chemists to an acceptable level. The modules include Liquid Chromatography, Gas Chromatography, Dissolution Testing, Thin-Layer Chromatography, Ultraviolet-Visible Spectrophotometry, Infrared Spectrophotometry, and Data Collection and Recording (as related to preparing worksheets in accordance with the requirements of the U.S. Food and Drug Administration). Each module is designed to be delivered in minimal time. By using a combination of commercial audiovisual materials and a training concept developed at DDA, the targeted group can be trained with minimal supervision. This approach does not require experienced analysts to be placed as full-time, one-on-one trainers; thus, the cost of the training is cut. The training scheme could be extended to other applications in industry, academia, or government by targeting training modules to their characteristic operation. These modules are also used as refresher courses for experienced analysts who have not practiced these techniques recently. The modular concept provides an excellent way to train employees quickly.
Rapid Analysis for Ivermectin Residue in Liver and Muscle Tissue by Liquid Chromatography
Authors: Reising Kyle P 
Published: February 2020

Abstract
A rapid procedure has been developed for the isolation and determination of ivermectin in liver and muscle tissue. The analyte is extracted from the target tissue with isooctane and isolated by coagulation of extraneous matrix residue at reduced temperature. A fluorescent derivative is prepared and analyzed by liquid chromatography. Recoveries of ovine, bovine, and porcine liver and muscle tissues fortified within a 0-60 ppb range averaged 75%, with a 12.7% coefficient of variation.