bluuebunny/crossref_metadata_2025_split huggingface dataset:
Total Arsenic Determination and Speciation in Infant Food Products by Ion Chromatography-Inductively Coupled Plasma-Mass Spectrometry
Authors: Vela Nohora P , Heitkemper Douglas T 
Published: July 2020

Abstract
Health risk associated with dietary arsenic intake may be different for infants and adults. Seafood is the main contributor to arsenic intake for adults while terrestrial-based food is the primary source for infants. Processed infant food products such as rice-based cereals, mixed rice/formula cereals, milk-based infant formula, applesauce and purée of peaches, pears, carrots, sweet potatoes, green beans, and squash were evaluated for total and speciated arsenic content. Arsenic concentrations found in rice-based cereals (63–320 ng/g dry weight) were similar to those reported for raw rice. Results for the analysis of powdered infant formula by inductively coupled plasma-mass spectrometry (ICP-MS) indicated a narrow and low arsenic concentration range (12 to 17 ng/g). Arsenic content in purée infant food products, including rice cereals, fruits, and vegetables, varies from &lt;1 to 24 ng/g wet weight. Sample treatment with trifluoroacetic acid at 100°C were an efficient and mild method for extraction of arsenic species present in different food matrixes as compared to alternative methods that included sonication and accelerated solvent extraction. Extraction recoveries from 94 to 128% were obtained when the summation of species was compared to total arsenic. The ion chromatography (IC)-ICP-MS method selected for arsenic speciation allowed for the quantitative determination of inorganic arsenic [As(III) + As(V)], dimethylarsinic acid (DMA), and methylarsonic acid (MMA). Inorganic arsenic and DMA are the main species found in rice-based and mixed rice/formula cereals, although traces of MMA were also detected. Inorganic arsenic was present in freeze-dried sweet potatoes, carrots, green beans, and peaches. MMA and DMA were not detected in these samples. Arsenic species in squash, pears, and applesauce were not detected above the method detection limit [5 ng/g dry weight for As(III), MMA, and DMA and 10 ng/g dry weight for As(V)].
Evaluation of the BAX® System for Detection of Listeria monocytogenes in Foods: Collaborative Study
Authors: Silbernagel Karen , Jechorek Robert , Barbour W Mark , Mrozinski Peter ,   Collaborators:, Alejo W , Aleo V , Andaloro B , Beacorn F , Benzinger J , Bogar S , Brayman C , Broom J , Carson M , Carver C , Cheng C , Centrella B , Clayborn J , Collins C , Deibel C , Divine M , Eliasberg S , Farmer D , Frye S , Gatesy T , Goodstein E , Halker C , Hall G , Hanson P , Hartman G , Heddaeus K , Hembree J , Hutchins J , Istafanos P , Jechorek R , Jenkins J , Kerdahi K , Kremer S , Lal A , Leighton S , Lester D , Lewis J , Lin J , Martin J , Maselli M , McCarthy P , McGovern B , Mills M , Mohnke F , Moon B , Moss D , Plaza M , Robeson S , Romero H , Rubalcaba D , Schultz A , Seehusen J , Shaw C , Siem K , Sloan E , Stanerson J , Stepanova N , Van K , Van Enkenvoort K , Vialpando M , Warren W , Watts K , Wilson K , Woodruff T 
Published: July 2020

Abstract
A multilaboratory study was conducted to compare the automated BAX® system and the standard cultural methods for detection of Listeria monocytogenes in foods. Six food types (frankfurters, soft cheese, smoked salmon, raw, ground beef, fresh radishes, and frozen peas) were analyzed by each method. For each food type, 3 inoculation levels were tested: high (average of 2 CFU/g), low (average of 0.2 CFU/g) and uninoculated controls. A total of 25 laboratories representing government and industry participated. Of the 2335 samples analyzed, 1109 were positive by the BAX system and 1115 were positive by the standard method. A Chi square analysis of each of the 6 food types, at the 3 inoculation levels tested, was performed. For all foods, except radishes, the BAX system performed as well as or better than the standard reference methods based on the Chi square results.
Optimization of Solid-Phase Microextraction for the Gas Chromatography/Mass Spectrometry Analysis of Persistent Organic Pollutants
Authors: Gago-Martínez Ana , Nogueiras María J , Rellán Sandra , Prado Juan , Alpendurada María F , Vetter Walter 
Published: July 2020

Abstract
In this work, solid-phase microextraction (SPME) has been applied as an alternative for the selective extraction of 3 polybrominated diphenyl ethers (PBDEs), 2,2′,4,4′-tetrabromodiphenyl ether (PBDE-47); 2,2′,4,4′,5-pentabromodiphenyl ether (PBDE-99); and 2,2′,4,4′,6-pentabromodiphenyl ether (PBDE-100), and 2 alkylphenols, 4-tert-OP and 4-NP, prior to their analysis by gas chromatography/mass spectrometry (GC/MS). The advantages of this technique are mainly its simplicity, cost-effectiveness, and time-saving sample preparation, as well as being a solvent-free technique. With the aim of optimizing the conditions for an efficient extraction of the studied compounds, different fiber coatings and the main parameters affecting the extraction procedure have been evaluated. The results obtained showed a good linearity in the range of concentrations investigated, and adequate relative standard deviation values were found according to the range accepted for SPME. Recovery values were in the range of 78–108%, and good detection and quantitation limits at ppt levels were obtained for both methods, allowing the determination of the selected compounds in samples at trace levels. The results obtained clearly show the potential of SPME for efficient concentration of the target compounds and also demonstrate the reliability of this extraction technique for their GC/MS analysis.
Evaluation of VIDAS Listeria monocytogenes II (LMO2) Immunoassay Method for the Detection of Listeria monocytogenes in Foods: Collaborative Study
Authors: Silbernagel Karen M , Carver Charles N , Jechorek Robert P , Johnson Ronald L ,   Collaborators:, Alejo W , Aleo V , Buresh J , Cagri A , Campbell S , Carson M , Chinault K , Clayborn J , Cook F , Dammann H , Dorn S , Elko B , Farmer D , Farmer R , Gasses T , Greiman L , Guzman C , Hemker M , Hintz C , Jechorek R , Jenkins J , Kexel N , Kildisg J , Knickerbocker J , Kora L , Koziczkowski J , Krieg D , Lal A , Lam L , Lau D , Loftis M , Madewell L , Matisko V , Miele A , Muzzy T , Park J , Peters C , Pickett J , Radermacher S , Romero H , Ross J , Rotten J , Rule P , Ryser E , Satterwhite L K , Schultz A , Shell D , Smith J , Storment E , Ulmer M , Walia J , Whetzel S , Woltman N 
Published: July 2020

Abstract
A multilaboratory study was conducted to compare the VIDAS®Listeria monocytogenes II (LMO2) immunoassay and the standard cultural methods for the detection of Listeria monocytogenes in foods. Five food types—vanilla ice cream, brie cheese, cooked roast beef, frozen green beans, and frozen tilapia fish—at 3 levels were analyzed by each method. A total of 26 laboratories representing government and industry participated. In this study, 1404 test portions were analyzed of which 1152 were used in the statistical analysis. There were 448 positive by the VIDAS LMO2 assay and 457 positive by the standard culture methods. A χ2 analysis of each of the 5 food types, at the 3 inoculation levels tested, was performed. The resulting χ2 value, 0.36, indicates that overall, there are no statistical differences between the VIDAS LMO2 assay and the standard methods at the 5% level of significance.
A Multiresidue Pesticide Monitoring Procedure Using Gas Chromatography/Mass Spectrometry and Selected Ion Monitoring for the Determination of Pesticides Containing Nitrogen, Sulfur, and/or Oxygen in Fruits and Vegetables
Authors: Mercer Gregory E , Hurlbut Jeffrey A 
Published: July 2020

Abstract
A procedure for the analysis of over 100 pesticides that only contain combinations of carbon, hydrogen, nitrogen, sulfur, and oxygen (i.e., no phosphorous or halogen atoms) has been developed. The procedure employs gas chromatography with a mass selective detector (GC/MSD), electron impact ionization, and selected ion monitoring. This GC/MSD procedure provided lower limits of quantitation and increased confirmational data compared to the traditional element-selective GC procedures that are commonly used for the detection of this “class” of pesticides. These analytical improvements were demonstrated by 26 pesticides that were detected at ng/g levels in a variety of fruit and vegetable matrixes using this procedure; these pesticides were missed by the traditional element-selective GC procedures. Validation of the procedure was performed using acetone extraction with solid-phase extraction cleanup. Twenty representative target pesticides were used to demonstrate repeatability and linearity of the chromatographic response and recovery from fruit and vegetable matrixes.
A Square-Wave Adsorptive Stripping Voltammetric Method for the Determination of Amaranth, a Food Additive Dye
Authors: Alghamdi Ahmad H 
Published: July 2020

Abstract
Square-wave adsorptive stripping voltammetric (AdSV) determinations of trace concentrations of the azo coloring agent Amaranth are described. The analytical methodology used was based on the adsorptive preconcentration of the dye on the hanging mercury drop electrode, followed by initiation of a negative sweep. In a pH 10 carbonate supporting electrolyte, Amaranth gave a well-defined and sensitive AdSV peak at −518 mV. The electroanalytical determination of this azo dye was found to be optimal in carbonate buffer (pH 10) under the following experimental conditions: accumulation time, 120 s; accumulation potential, 0.0 V; scan rate, 600 mV/s; pulse amplitude, 90 mV; and frequency, 50 Hz. Under these optimized conditions the AdSV peak current was proportional over the concentration range 1 × 10−8 − 1.1 × 10−7 mol/L (r = 0.999) with a detection limit of 1.7 × 10−9 mol/L (1.03 ppb). This analytical approach possessed enhanced sensitivity, compared with conventional liquid chromatography or spectrophotometry and it was simple and fast. The precision of the method, expressed as the relative standard deviation, was 0.23%, whereas the accuracy, expressed as the mean recovery, was 104%. Possible interferences by several substances usually present as food additive azo dyes (E110, E102), gelatin, natural and artificial sweeteners, preservatives, and antioxidants were also investigated. The developed electroanalyticals method was applied to the determination of Amaranth in soft drink samples, and the results were compared with those obtained by a reference spectrophotometric method. Statistical analysis (paired t-test) of these data showed that the results of the 2 methods compared favorably.
Flow-Through Fluorescence-Based Optosensor with On-Line Solid-Phase Separation for the Simultaneous Determination of a Ternary Pesticide Mixture
Authors: Llorent-Martínez Eulogio J , García-Reyes Juan F , Ortega-Barrales Pilar , Molina-Díaz Antonio 
Published: July 2020

Abstract
A rapid and selective method was developed for the simultaneous determination of 3 widely used pesticides, carbendazim (CBZ), carbofuran (CF), and benomyl (BNM). The method utilized a single continuous-flow, solid surface fluorometric multioptosensor implemented with a previous separation of the analytes on a minicolumn, placed just before the sensor, that was packed with the same solid support (C18 silica gel) as the flow-through cell. The separation was achieved because of the different kinetics of retention/elution of the pesticides on the solid support in the minicolumn, enabling the sequential arrival of the analytes at the sensing zone. With a single injection of the mixture, 2 of them were more strongly retained in the minicolumn (CF and BNM) while the other (CBZ) passed through the system towards the sensing material where it developed its fluorescence transitory signal. Then, CF and BNM were successively eluted from the solid support using 2 different eluting solutions, and they sequentially reached the sensing zone and developed their respective signals. A multiwavelength fluorescence detection mode was used, recording the signals of each pesticide at its maximum excitation/emission wavelength; therefore, the sensitivity was increased. The system was calibrated using a sample volume of 2000 μL. The linear dynamic range was 80–1400, 250–2400, and 150–2000 ng/mL with detection limits of 15, 68, and 35 ng/mL and relative standard deviation values of 3.5, 3.2, and 2.4% for CBZ, CF, and BNM, respectively. A recovery study was applied to spiked environmental water samples, and recoveries ranged from 96 to 104%.
Multiresidue Determination of Fluoroquinolones in Shrimp by Liquid Chromatography-Fluorescence-Mass Spectrometryn
Authors: Schneider Marilyn J , Vazquez-Moreno Luz , Bermudez-Almada Maria del Carmen , Guardado Ramon Barraza , Ortega-Nieblas Magdalena 
Published: July 2020

Abstract
An efficient multiresidue method for analysis of fluoroquinolones in shrimp has been developed in which quantitation by fluorescence and confirmation by Multiple Stage Mass Spectrometry (MSn) is achieved simultaneously. In this method, shrimp tissue is extracted with ammoniacal acetonitrile and the extract is defatted and then evaporated. After dissolution in basic phosphate buffer, fluoroquinolones in the extract are separated by liquid chromatography and quantitated, taking advantage of their intense fluorescence. Eluate from the fluorescence detector enters the MSn, which allows for confirmation by monitoring ratios of 2 prominent product ions in the MS3 or MS2 spectrum. Using this method, 8 fluoroquinolones have been analyzed in shrimp samples fortified at 10, 25, 50, or 100 ppb levels. Recoveries for desethyleneciprofloxacin, norfloxacin, ciprofloxacin, danofloxacin, enrofloxacin, orbifloxacin, sarafloxacin, and difloxacin ranged from 75 to 92%, with relative standard deviation values of &lt;6%. The limits of quantitation ranged from 0.1 to 1 ng/g. Enrofloxacin and ciprofloxacin were also successfully determined in enrofloxacin-incurred shrimp using this method.
High-Performance Thin-Layer Chromatography Determination of Some Antimycotic Imidazole Derivatives and Preservatives in Medicinal Creams and a Gel
Authors: Čakar Mira , Popović Gordana , Agbaba Danica 
Published: July 2020

Abstract
Simple and reliable thin-layer chromatography-densitometry methods for determination of antimycotics (bifonazole, clotrimazole, and miconazole) and preservatives (benzyl alcohol and benzoic acid) were developed. The pairs bifonazole/benzyl alcohol, clotrimazole/benzyl alcohol, and miconazole/benzoic acid were determined simultaneously. The following mobile phases were used: ethyl acetate–n-heptane–methanol–diethylamine (3 + 4.5 + 1 + 0.2, v/v/v/v) for bifonazole and benzyl alcohol; n-butyl acetate–n-heptane–methanol–dietylamine (3 + 4.5 + 1 + 0.2, v/v/v/v) for clotrimazole and benzyl alcohol; and n-butyl acetate–carbon tetrachloride–methanol–diethylamine (3 + 6 + 2.5 + 0.5, v/v/v/v) for miconazole and benzoic acid. The chromatographic zones on silica gel plates were scanned in the reflectance/absorbance mode at 230 nm (bifonazole, benzyl alcohol, miconazole, and benzoic acid) and 210 nm (clotrimazole and benzyl alcohol). The recovery for all substances ranged from 98.7 to 100.7%. The limits of detection and quantitation were 0.03 to 0.2 μg and 0.1 to 0.5 μg/spot, respectively. The proposed methods were applied for determination of antimycotics and preservatives in commercially available pharmaceuticals.
Comparison of Methods for Extraction of Ethyl Carbamate from Alcoholic Beverages in Gas Chromatography/Mass Spectrometry Analysis
Authors: Mirzoian Armen , Mabud Md. Abdul 
Published: July 2020

Abstract
A procedure to analyze ethyl carbamate (EC) by gas chromatography/mass spectrometry was optimized and validated. Deuterated EC (d5-EC) was added to the samples as an internal standard followed by extraction with polystyrene crosslinked polystyrene cartridges using minimal volumes of ethyl acetate. The EC response was measured in selective ion monitoring (SIM) mode and found to be linear in the range between the limit of quantitation (10 μg/L) and 1000 μg/L. EC recoveries varied from 92 to 112%, with the average value of 100 ± 8%. The procedure compared well (r2 = 0.9970) with the existing AOAC Official Method with the added benefits of minimal solvent usage and reduced matrix interferences.
Determination of Chloramphenicol in Royal Jelly by Liquid Chromatography/Tandem Mass Spectrometry
Authors: Jiang Yuan , Xu Jin-Zhong , Shen Chong-Yu , Ding Tao , Chen Hui-Lan , Wu Bin , Shen Wei-Jian 
Published: July 2020

Abstract
A liquid chromatographic/tandem mass spectrometric method was developed and validated for the determination of chloramphenicol (CAP) in royal jelly. Royal jelly samples were first denatured with lead acetate solution, and the CAP was extracted with solid-phase extraction before separation by liquid chromatography. A triple-quadrupole mass spectrometer operated in the negative electrospray ionization and selected-reaction monitoring mode was used for the detection of CAP. For method validation, royal jelly samples were fortified at CAP levels between 0.1 and 10.0 μg/kg; at these levels, recovery values (internal standard-corrected) ranged from 93.3 to 105.0%, and the within-laboratory reproducibility (relative standard deviation) was ≤9.1%. The decision limit was 0.07 μg/kg, and the detection capability was 0.1 μg/kg.
An Electrochemiluminescence-Based Competitive Displacement Immunoassay for the Type-2 Brevetoxins in Oyster Extracts
Authors: Poli Mark A , Rivera Victor R , Neal Dwayne D , Baden Daniel G , Messer Shawn A , Plakas Steven M , Dickey Robert W , Said Kathleen El , Flewelling Leanne , Green David , White Jill 
Published: July 2020

Abstract
A new competitive electrochemiluminescence-based immunoassay for the type-2 brevetoxins in oyster extracts was developed. The assay was verified by spiking known amounts of PbTx-3 into 80 methanol extracts of Gulf Coast oysters. We also provide preliminary data demonstrating that 100 acetone extracts, aqueous homogenates, and the clinical matrixes urine and serum can also be analyzed without significant matrix interferences. The assay offers the advantages of speed (≃ 2h analysis time); simplicity (only 2 additions, one incubation period, and no wash steps before analysis); low limit of quantitation (conservatively, 50 pg/mL 1 ng/g tissue equivalents); and a stable, nonradioactive label. Due to the variety of brevetoxin metabolites present and the lack of certified reference standards for liquid chromatographymass spectrometry confirmation, a true validation of brevetoxins in shellfish extracts is not possible at this time. However, our assay correlated well with another brevetoxin immunoassay currently in use in the United States. We believe this assay could be useful as a regulatory screening tool and could support pharmacokinetic studies in animals and clinical evaluation of neurotoxic shellfish poisoning victims.
Simultaneous Determination of a Ternary Mixture of Doxylamine Succinate, Pyridoxine Hydrochloride, and Folic Acid by the Ratio SpectraZero-Crossing, Double DivisorRatio Spectra Derivative, and Column High-Performance Liquid Chromatographic Methods
Authors: Pathak Ashutosh , Rajput Sadhana J 
Published: July 2020

Abstract
Three simple, rapid, and accurate methods, i.e., the derivative ratio spectrazero-crossing method (method I), double divisorratio spectra derivative method (method II), and column reversed-phase high-performance liquid chromatographic (RP-HPLC) method (method III) were developed for the simultaneous determination of doxylamine succinate (DOX), pyridoxine hydrochloride (PYR), and folic acid (FA) in their ternary mixtures and in tablets. In methods I and II, the calibration graphs were linear in the range of 2.580, 1.040, and 1.030 g/mL for DOX, PYR, and FA, respectively. In the HPLC method, the separation of these compounds was performed using mobile phase consisting of 0.05 M phosphate buffer (pH 6.3)methanolacetonitrile (50 + 20 + 30, v/v/v), and UV detection was performed at 263 nm. Linearity was observed between the concentrations of the analytes and peak areas [correlation coefficient (r) 0.9998] in the concentration range of 1.0200, 4.0600, and 4.0600 g/mL for DOX, PYR, and FA, respectively. The standard deviation of retention time in method III was 0.011, 0.015, and 0.016 for DOX, PYR, and FA, respectively. The precision studies for all of the methods gave relative standard deviation values of &lt;2. The results obtained from the methods were statistically compared by means of Student's t-test and the variance ratio F-test. It was concluded that all of the developed methods were equally accurate, sensitive, and precise. These methods could be applied to determine DOX, PYR, and FA in their combined dosage forms.
Quantification of Glycyrrhizin in Glycyrrhiza Glabra Extract by Validated HPTLC Densitometry
Authors: Gantait Arunava , Pandit Subrata , Nema Neelesh K , Mukjerjee Pulok K 
Published: July 2020

Abstract
Glycyrrhiza Glabra Linn (Family-Fabaceae) is active as an anti-allergic, anti-inflammatory, spasmolytic, mild laxative, antistress, antidepressive, antiulcer, liver protective, estrogenic, emmenagogue, and antidiabetic substance, and is widely used in the Indian system of medicine. The major bioactive constituent is glycyrrhizin. A simple HPTLC method has been developed to control the quality of raw as well as finished glycyrrhiza using glycyrrhizin as the bioactive marker. The solvent system was optimized to chloroformmethanolwater (65 + 36 + 7.5, v/v/v). Extract and standard were dissolved in 70 methanol and applied on a precoated TLC plate. After development, the plate was scanned at 254 nm to create a chromatogram, then the quantity of glycyrrhizin was determined in the extract. The method was validated in terms of specificity, linearity, precision, LOD, and LOQ. Linearity range was found to be 0.964.80 g per spot. The linearity relationship was described by the equation: Y 612.706 + 1.091X (with r 0.99904 and SD 2.52), where Y is the area under curve and X is the amount of glycyrrhizin (ng). The amount of glycyrrhizin found in the extract was 9.1. Thus, the method provides a rapid and cost-effective quality measure for Glycyrrhiza Glabra hydroalcoholic extract.
Determination of Fumonisins B1 and B2 in Corn by LC/MS with Immunoaffinity Column Cleanup: Interlaboratory Study
Authors: Senyuva Hamide Z , Gilbert John , Stroka Joerg ,   Collaborators:, Biselli S , De Girolamo A , De Rijk T , De Saeger S , Köppen R , MacDonald S , Neumann G , Patel S , Seefelder W , Tibet U , Trucksess M W , van Osenbruggen W A , Zachariášová M 
Published: July 2020

Abstract
An interlaboratory validation study was conducted to establish the method performance characteristics of an immunoaffinity column (IAC) cleanup procedure followed by LC/MS for the determination of fumonisins B1 (FB1) and B2 (FB2) and combined FB1 + FB2 in corn. The test portion is extracted with acetonitrilemethanolwater (25 + 25 + 50). The extract is filtered, diluted with phosphate-buffered saline solution, and applied to an IAC. FB1 and FB2 are removed with methanol, followed by water, then directly determined by RPLC with MS detection using selected-ion monitoring of two characteristic ions in each case. Naturally contaminated corn samples were milled to a fine powder and mixed to produce three samples with target levels of combined FB1 + FB2 ranging from 350 to 4000 g/kg. Of 15 initially participating laboratories, two failed to report results and another did not follow the prescribed method. Thus, valid results were obtained from 12 participants located in 11 countries. Statistical analysis of the results produced RSDr values of 4.611.9, 1.912.6, and 1.411.5 for FB1, FB2, and combined FB1 + FB2, respectively; the corresponding RSDR values were 19.823.8, 18.225.5, and 18.823.2. The three concentration levels of combined FB1 + FB2 were 534, 1194, and 1954 g/kg. HorRat values for r and R were all &lt;2.0, indicating that the method is suitable as a regulatory method for the enforcement of European Union limits for fumonisins in corn.