bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of Standard Reference Material 2383 (Baby Food Composite) and Use of an Interlaboratory Comparison Exercise for Value Assignment of Its Nutrient Concentrations
Authors: Sharpless Katherine E , Gill Lisa M , Margolis Sam A , Wise Stephen A , Elkins Edgar 
Published: February 2020

Abstract
The preparation of the recently released Standard Reference Material (SRM) 2383 Baby Food Composite and the process used for value assignment of nutrient concentrations are reported. SRM 2383 can be used as a control material when assigning values to in-house control materials and when validating analytical methods for measuring proximates, vitamins, and minerals in baby food and similar matrixes. The SRM was prepared as a commercial baby food would be prepared, with the same ingredients. The Certificate of Analysis for SRM 2383 provides assigned values for concentrations of proximates, vitamins, and minerals for which product labeling is required by the Nutrition Labeling and Education Act of 1990. These assigned values were based on measurements by the National Institute of Standards and Technology (NIST) and/or collaborating laboratories. Assignment of analyte concentrations based solely on analyses by collaborating laboratories is described in this paper. Certified values are provided for retinol, tocopherols, and several carotenoids including total β-carotene; the certification of and methodology used for measurement of these analytes is discussed in a companion paper (this issue, page 288). Reference values are provided for solids, ash, fat, nitrogen, protein, carbohydrate, calories, vitamin B1, vitamin B2, vitamin B6, niacin, biotin, calcium, phosphorus, magnesium, manganese, iron, zinc, copper, sodium, potassium, and chloride. Reference values for additional carotenoids are reported in the companion paper (this issue, page 288). Information values are provided for iodine, selenium, molybdenum, vitamin D, vitamin B12, folic acid, pantothenic acid, choline, inositol, sugars, total dietary fiber, and 3 classes of fats.
Raman Spectroscopic Characterization of RP-18-Type Chemically Bonded Stationary Phases for Liquid Chromatography
Authors: Kowalik Gabriela , Rogosz Krystyna , Kowalska Teresa 
Published: February 2020

Abstract
This study is the first Raman spectroscopic characterization of conventional chemically bonded liquid chromatographic (LC) stationary phases of the RP-18 type using the high-power Nd:WV04 neodymium laser. Raman spectra were obtained for octadecyl (C18) chemically bonded silica-based stationary phases, as well as for silica, aminopropyl (NH2), cyanopropyl (CN), diol (OH), octyl (C8), and methyl (C1) phases for comparison. This study demonstrates that Raman spectroscopy using the high-power neodymium laser can be used to study RP-18-type LC stationary phases and to quantitate the density of coverage of the silica matrix with octadecyl ligands. The paper presents the experimental setup and conditions usedto obtain Raman spectra of commercial RP-18-type chemically bonded stationary phases and examines the spectroscopic similarities and differences observed for different bonded ligands typically used in reversed-phase and normal-phase LC separations.
Personal Overpressured-Layer Chromatography (OPLC) Basic System 50, Flexible Tool in Analytical and Semipreparative Work
Authors: Mincsovics Emil , Garami Márta , Kecskés László , Tapa Barnabás , Végh Zoltán , Kátay György , Tyihák Ernó 
Published: February 2020

Abstract
A new automated overpressured-layer chromatographic (OPLC) system called the Personal OPLC Basic System 50 is suitable for analytical and semi preparative separations. The automatic microprocessor-controlled system ensures rapid and reproducible off-line isocratic and stepwise gradientseparations. High external pressure (5 MPa) makes the sorbent layer more homogeneous, yielding more efficient off-line separation compared with those by early Chrompres chambers. A theoretical plate height of 10–30 μm can be achieved on an analytical high-performance thin-layer chromatographic (HPTLC) layer made of irregular silica gel with an average particle size of 5 μm if an optimal linear velocity (20–40 mm/min) and a nonviscous solvent system are used. On an analytical layer of 3 μm spherical silica gel, a theoretical plate height of 6–15 μm can be reached. Rapid analytical separations of resveratrol (1555 s) and xanthine by one-(498s) and two-directional (274 s) off-line developments were accomplished. On-line separation and detection combined with off-line sample application and fully on-line processing (including on-line sample application, separation, and detection) were fulfilled with a TLC plate for xanthine separation. Semi preparative isolation of xanthines was achieved through a fully on-line OPLC operating mode and scaled-up chromatography.
Stability-Indicating Methods for Determining Omeprazole and Octylonium Bromide in the Presence of Their Degradation Products
Authors: EL-Kousy Naglaa M , Bebawy Lories I 
Published: February 2020

Abstract
Four stability-indicating assays were developed for determining omeprazole and octylonium bromide. Omeprazole is photodegraded and estimated in the presence of its degradation products sul-phenamide (I) and benzimidazole sulphide (II) by 2 methods. The first method depends on use of first-, second-, and third-derivative spectrophotometry at 290.4,320.6, and 311.6 nm, respectively. The second method is based on applying the charge-transfer technique with chloranil as π acceptor to form a complex with omeprazole, the absorbance of which is measured at 377 nm. These methods determine omeprazole in concentration ranges of 5–20 μg/mL by first-, second-, and third-derivative spectrophotometry and 10–50 μg/mL by charge-transfer complexation with mean accuracies of 99.92 ± 0.73, 99.71 ±1.02, 99.64 ± 0.66, and 100.24± 0.81%, respectively. Octylonium bromide is determined by a densitometric method using thin-layer chromatography in the presence of its degradation products p-[2-(n-octyoxy)benzoyl]-aminobenzoic acid(III) and diethyl-(2-hydroxyethyl)methyl ammonium bromide (IV) without any interferences. Alternatively, octylonium bromide is evaluated by a colorimetric method using the acid dye rose bengal. The ion pair formed is extracted in chloroform at pH 4, and its absorbance is measured at 562 nm. These methods determine octylonium bromide in the presence of its degradation products in concentration ranges of 0.1–0.5 μg/μL by densitometry and 4.5–22.5 μg/mL by colorimetry, with mean accuracies of 100.21 ± 0.93 and 99.73 ±0.89%, respectively. The suggested methods were used to determine drugsin bulk powder, laboratory-prepared mixtures,and pharmaceutical dosage forms. Results werecompared statistically with those obtained with reference methods.
Determination of Flumequine in Channel Catfish by Liquid Chromatography with Fluorescence Detection
Authors: Plakas Steven M , El Said Kathleen R , Bencsath F Aladar , Musser Steven M , Walker Calvin C 
Published: February 2020

Abstract
Rapid methods are described for determination of flumequine (FLU) residues in muscle and plasma of farm-raised channel catfish (Ictalurus punctatus). FLU residues were extracted from tissues with an acidified methanol solution, and extracts were cleaned up on C18 solid-phase extraction cartridges. FLU concentrations were determined by liquid chromatography (LC)using a C18 analytical column and fluorescence detection (excitation, 325 nm; emission, 360 nm). Mean recoveries of FLU from fortified muscle were 87–94% at 5 levels ranging from 10 to 160 ppb (5 replicates per level). FLU recoveries from fortified plasma were 92–97% at 5 levels ranging from 20 to 320 ppb. Limits of detection (signal-to-noise ratio, 3:1)for the method as described were 3 and 6 ppb for muscle and plasma, respectively. Relative standard deviations (RSDs) for recoveries were ≤12%. Live catfish were dosed with 14C-labeled or unlabeled FLU to generate incurred residues. Recoveries of 14C residues throughout extraction and cleanup were 90 and 94% for muscle and plasma, respectively. RSDs for incurred FLU at 2 levels in muscle and plasma ranged from 2 to 6%. The identity of FLU in incurred tissues was confirmed by LC/mass spectrometry.
Reveal for Salmonella Test System
Authors: Bird Charles B , Miller Raymond L , Miller Brinton M 
Published: February 2020

Abstract
The Reveal for Salmonella(RSS) test system is a presumptive qualitative test that detects the presence of Salmonella organisms in foods within 21 h total testing time, allowing the user to release negative products 24 h earlier than when using other rapid test kits. Foods are enriched with a proprietary resuscitation medium called Revive and then selectively enriched with either Selenite Cystine or Rappaport-Vassiliadis selective media. The enriched culture is used to inoculate the RSS detection device, which initiates a lateral flow through areagent zone containing anti-Salmonella antibodies conjugated to colloidal gold particles that capture antigens present in the culture. The antigen–antibody complex migrates farther and is captured by an additional anti-Salmonella antibody, causing the colloidal gold to precipitate and form a visual line, indicating a positive result. A procedural control line also will form regardless of the presence of Salmonella organisms to indicate the test is working properly. Existing AO AC Official Methods for Salmonella organisms require a 48 h enrichment before testing. Hence, a food product has to be held before release, adding extra cost to the company and the consumer. The RSS test system was evaluated by quantitative spiking studies. Although AOAC encourages inclusion of naturally contaminated foods, almost all microbiological AOAC validation studies have been performed with artificially contaminated foods for absolute control over the study. The RSS test system is designed to test many food types for Salmonella organisms and has a limit of detection of 5–10 colony-forming units (cfu)/25 g with a false-negative rate of &lt;1 % and a false-positive rate of &lt;5.0%. It showed an 81 % overall agreement with the traditional procedure of the U.S. Department of Agriculture’s Food Safety Inspection Service.
The Impact of Household Preparations on the Residues of Pesticides in Selected Agricultural Food Commodities Available in India
Authors: Ramesh Atmakuru , Balasubramanian Muthukrishnan 
Published: February 2020

Abstract
Gas chromatographic multiresidue methods for simultaneous determination of organophosphorus, organochlorine, and organonitrogen pesticides were used to study the exposure of the Indian population to pesticide contamination at their actual dietary intakes. Selected agricultural commodities—5 kinds of vegetables (tomato, potato, okra, cabbage, and green beans), 6 kinds of cereals and pulses (rice, maize, wheat, red gram, black gram, and green gram), and 6 kinds of fruits (mango, orange, guava, banana, apple, and grapes)—readily available in Chennai City local markets—were studied for this purpose. Samples were fortified with known concentrations of various pesticides and subjected to household preparation methods commonly used in India. The impact of household preparation is very high, resulting in 65–95% decontamination of pesticides at different stages. Of 512 raw market samples analyzed, the organo chlorine and organophosphorus pesticides present in 12 samples were removed during household preparations, resulting in residues well below the toxicologically acceptable limits.
Measurement of Sugars and Starches in Foods by a Modification of the AOAC Total Dietary Fiber Method
Authors: Casterline James L , Oles Carolyn J , Ku Yuoh 
Published: February 2020

Abstract
A separation scheme for the determination of sugars and starch in processed food was developed. It is based on AOAC Method 985.29 for total dietary fiber with these modifications: carbohydrate starches are separated into soluble and insoluble fractions before they are hydrolyzed; acetonitrile is used instead of ethanol to separate sugars from enzyme-resistant carbohydrates, proteins, and other macromolecules; and a solid-phase extraction filter is included to remove substances that interfere with high-performance liquid chromatography (HPLC). Recovery studies indicate a &gt;97% sugar recovery. Twenty foods were analyzed. After enzymatic hydrolysis, fructose, glucose, sucrose, maltose, and lactose were extracted and determined by HPLC using a refractive index detector. Starch content was calculated from the increase in the amount of glucose. The results were compared with values listed on the “Nutrition Facts” panel for that food. The analyzed amounts of sugars and starches were 73–96% of declared values.
An Improved Method for Analysis of Cholecalciferol-Treated Baits
Authors: Mauldin Richard E , Johnston John J , Riekena Craig A 
Published: February 2020

Abstract
A liquid extraction method is described that permits rapid determination of cholecalciferol (D3) in rodenticidal grain baits. Purified D3 was incubated for various time periods to produce pre-D3. Response ratios (concentration/detector response) for various concentrations of pre-D3 and D3 in solutions permitted generation of a correction factor for direct quantitation of pre-D3 in solutions with a pure D3 standard. The method has equal precision and accuracy, yet is simpler and less time consuming and requires less solvents than widely accepted methods for extracting D3 from grain baits. Recoveries from control oat baits fortified at 0.05 and 0.75 wt% were 100.9 and 98%, respectively. A standard curve for concentrations ranging from 6.4 to 204 μg/mL had an r2 of 0.9999 and an intercept of zero and was linear and proportional. The method limit of detection was 2.0 × 10−4 wt % D3.
Comparisons of Karl Fischer Method with Oven Methods for Determination of Water in Forages and Animal Feeds
Authors: Thiex Nancy , Van Erem Terri 
Published: February 2020

Abstract
In a comparative study of the Karl Fischer method with oven methods for determination of water in forages and animal feeds, oven methods yielded the following relative recoveries (expressed as a percentage of the recovery obtained by the Karl Fischer method) for hay, haylage, and corn silage, respectively: (1) drying at 135°C for 2 h (AOAC 930.15), 113,162, and 133%; (2) drying at 104°C for 3 h (AOAC 935.29), 96,122, and 113%; and (3) drying at 104°C for 6 h, 97, 129, and 117%. Relative recoveries for nonurea-containing and urea-containing feed, respectively, were as fol lows: (1) drying at 135°C for 2 h (AOAC 930.15), 116 and 2746% (2) drying at 104°C for 3 h (AOAC 935.29), 88 and 239%; (3) drying at 95°C for 5 h under vacuum (AOAC 934.01), 83 and 727% (4) drying at 104°C for 6 h, 90 and 427%; and (5) drying at 110°C for 3 h, 94 and 425%. Preliminary near-infrared reflectance calibrations for water (moisture) based on the Karl Fischer method were promising (r2 = 0.98; standard error of calibration = 0.20).
Validation Study for the Determination of Tetracycline Residues in Animal Tissues
Authors: Posyniak Andrzej , Zmudzki Jan , Ellis Richard L , Semeniuk Stanislaw , Niedzielska Jolanta ,   Collaborators:, Andrzejak R , Cabon J , Jaromin E , Milian A , Rodziewicz L , Zuczek G 
Published: February 2020

Abstract
An interlaboratory study of the liquid chromatographic (LC) determination of tetracyclines—oxytetracycline (OTC), tetracycline (TTC), and chlortetracycline (CTC)—in animal tissues was conducted. Isolation was performed with oxalic buffer followed by dechelation and deproteination with oxalic acid–acetonitrile. The extract was cleaned with a styrene–divinylbenzene cartridge. LC analysis was performed with a PLRP-S column and 0.01 M oxalic acid–acetonitrile (75 + 25, v/v) as mobile phase. Participants analyzed 2 control and 10 fortified porcine muscle and kidney samples. Additionally, porcine muscle samples containing incurred residues of tetracyclines were analyzed. Mean recoveries of fortified residues from porcine tissue ranged from 76.00 to 86.89%. Repeatabilities varied from 2.05% for OTC to 3.61 % for TTC for muscle samples and from 6.75% for CTC to 8.74% for OTC for kidney samples. Reproducibilities ranged from 2.05 to 4.30% for muscle samples and from 15.77 to 18.81 % for kidney samples.
Surveillance and Control of Aflatoxins B1, B2, G1, G2, and M1 in Foodstuffs in the Republic of Cyprus: 1992–1996
Authors: Ioannou-Kakouri Eleni , Aletrari Maria , Christou Eftychia , Hadjioannou-Ralli Artemisia , Koliou Athena , Akkelidou Dina 
Published: February 2020

Abstract
Aflatoxins (AFs) B1, B2, G1, and G2 in locally produced and imported foodstuffs (nuts, cereals, oily seeds, pulses, etc.) were monitored and controlled systematically and effectively from 1992–1996. Samples (peanuts, pistachios, etc.) with total AFs above the Cyprus maximum level (ML) of 10 μg/kg fluctuated between 0.7 and 6.9%. The results indicate the effectiveness of monitoring, as well as the need for constant surveillance and control, especially at critical control points (sites of import, primary storage, etc.), to prevent unfit products from entering the Cyprus market. The control included sampling, retainment, analysis, and destruction of foodstuff lots with AF levels above MLs. The highest incidence of aflatoxin contamination was observed in peanut butter (56.7%) and the highest level of AF B1 was found in peanuts (700 μg/kg). Levels of AF M1 in raw and pasteurized milk analyzed in 1993,1995, and 1996 were within both the Cyprus ML (0.5 μg/L) and the lower ML (0.05 μg/L) of some European countries. Only 12% of samples had detectable levels of AF M1. Analyses were performed by immunochemical methods. When recoveries were lower than 80%, the AF levels were corrected for recovery.
Flow-Injection Spectrophotometric Determination of Phenolic Drugs and Carbamate Pesticides by Coupling with Diazotized 2,4,6-Trimethylaniline
Authors: Alvarez-Rodriguez Lluis , Josep Esteve-Romero , Escrig-Tena Imma , Alvarez-Coque M Celia Garcia 
Published: February 2020

Abstract
A flow-injection (FI) spectrophotometric system is proposed for the determination of phenols and carbamates. In the FI manifolds, the solutions of phenols or carbamates (the latter after hydrolysis with NaOH) were injected into a diazonium ion carrier stream at pH 9.5 (buffered with tetrahydroborate), which was formed by mixing 2,4,6-trimethylaniline (TMA) with nitrate in a sodium dodecyl sulfate aqueous micellar medium. Absorbance was measured at 550 nm. The system combines the advantages derived from the use of TMA for the coupling of phenols in basic micellar media, because of the inhibition of the self-coupling reaction of the reagent, with the precision and speed of the FI procedures. Other diazotized reagents produced excessive blank signals. The procedures were successfully applied to the determination of phenolic drugs (epinephrine, acetaminophen, and guaiacol) in pharmaceuticals and carbamates (bendiocarb, benfuracarb, carbaryl, carbofuran, methiocarb, promecarb, and propoxur) in pesticide products and water samples.
Monitoring Pesticide Residues in Egyptian Fruits and Vegetables in 1995
Authors: Dogheim Salwa M , Alla Sohair A Gad , El-Marsafy Ashraf M , Fahmy Safaa M 
Published: February 2020

Abstract
Organophosphorus, dithiocarbamates, and some synthetic pyrethroids pesticides, which are commonly used in Egypt for pest control, were monitored, as well as persistent organochlorines, which had been prohibited from use several years ago. Fruit and vegetable samples (397) were collected from 8 local markets and examined for 52 pesticides. Of all analyzed samples, 42.8% contained detectable residues, of which 1.76% exceeded their maximum residue limits (MRLs). The rates of contamination with the different pesticides were 0-86%. However, violation rates among contaminated products were very low, ranging from 0 to 4.6%. In general, organochlorine pesticide residues were not detected in most samples. Dithiocarbamate residues were found in 70.4% of 98 samples analyzed for dithiocarbamates, but only one grape sample had residues exceeding the MRL established by the Codex Committee on Pesticide Residues.
Determination of Arsenic in Traditional Chinese Medicine by Microwave Digestion with Flow Injection-Inductively Coupled Plasma Mass Spectrometry (FI-ICP-MS)
Authors: Ong Eng-Shi , Yong Yuk-Lin , Woo Soo-On 
Published: February 2020

Abstract
A simple, rapid, and sensitive method with high sample throughput was developed for determining arsenic in traditional Chinese medicine (TCM) in the form of uncoated tablets, sugar-coated tablets, black pills, capsules, powders, and syrups. The method involves microwave digestion with flow injection-inductively coupled plasma mass spectrometry (FI-ICP-MS). Method precision was 2.7-10.1 % (relative standard deviation, n = 6) for different concentrations of arsenic in different TCM samples analyzed by different analysts on different days. Method accuracy was checked with a certified reference material (sea lettuce, Ulva lactuca, BCR CRM 279) for external calibration and by spiking arsenic standard into different TCMs. Recoveries of 89-92% were obtained for the certified reference material and higher than 95% for spiked TCMs. Matrix interference was insignificant for samples analyzed by the method of standard addition. Hence, no correction equation was used in the analysis of arsenic in the samples studied. Sample preparation using microwave digestion gave results that were very similar to those obtained by conventional wet acid digestion using nitric acid.
Simultaneous Determination of Chlorthalidone and Spironolactone with Univariate and Multivariate Calibration: Wavelength Range Selection
Authors: Luis M Luz , García José M , Jiménez Francisco , Jiménez Ana I , Arias Juan J 
Published: February 2020

Abstract
Chlorthalidone and spironolactone were determined simultaneously with the aid of univariate and multivariate calibration methods. Univariate calibration was performed by the zero-crossing and derivative ratio spectrum methods. Extensive spectral overlap and the scarcity of wavelengths in derivative spectra allowing one analyte to be distinguished and quantitated in the presence of the other gave rise to poor results that called for multivariate calibration. Partial least-squares regression was used in combination with a suitable method for selecting the optimum wavelength range and number of factors for analysis. The ensuing method was applied to simultaneous determination of chlorthalidone and spironolactone in a commercially available pharmaceutical preparation. The results were validated by high-performance liquid chromatography.
Solid-Phase Extraction Method for Patulin in Apple Juice and Unfiltered Apple Juice
Authors: Trucksess Mary W , Tang Yifeng 
Published: February 2020

Abstract
Patulin, a mold metabolite, is commonly found in rotting apples. Some countries regulate patulin at levels ranging from 30 to 50 μg/L. Most analytical methods for patulin in apple juice include liquid—liquid partitions. A solid¯phase extraction method has been developed for apple juice and unfiltered apple juice in the United States. A portion of the test sample (5 mL) was passed through a macroporous copolymer cartridge and was washed with 1 mL 1 % sodium bicarbonate and then with 1 mL 1 % acetic acid. Patulin was eluted with 3 mL 2% acetonitrile in anhydrous ethyl ether and was determined by reversed-phase liquid chromatography with UV detection at 276 nm. Recoveries ranged from 93 to104% in test samples spiked at 20-100 μg/L.