bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous Ion Removal and Quantitation of Low-Molecular-Weight Dietary Fiber from High-Molecular-Weight Dietary Fiber Filtrates Using Liquid Chromatography
Authors: Post Brett E , Marshak Michael R , DeVries Jonathan W 
Published: February 2020

Abstract
Dietary fiber and its quantitation in foods have been of significant interest in the nutrition community for over 50 years. A number of AOAC Official Methods of AnalysisSM have been adopted for the analysis of dietary fiber and some of its fractions and components commensurate with the evolving discoveries of dietary fiber nutrition research. Quantitation of low-molecular-weight soluble dietary fiber (LMWSDF) has been difficult due to high solubility in a precipitating solvent mixture of four parts alcohol and one part water. AOAC Method 2001.03 effectively quantitates LWMSDF subsequent to gravimetric removal of high-molecular-weight dietary fiber using LC. However, deionization and concentration of the enzymatic digestate, necessary to assure accurate LC quantitation, requires substantial time and manual labor. A modification to the method and resulting method performance is presented that describes a means of simultaneously deionizing the digestate and quantitating the LMWSDF in a single LC injection, eliminating a number of time-consuming manual preparation steps.
Development and Validation of a Multiresidue Method for the Determination of Neonicotinoid and Macrocyclic Lactone Pesticide Residues in Milk, Fruits, and Vegetables by Ultra-Performance Liquid Chromatography/MS/MS
Authors: Kamel Alaa , Qian Yaorong , Kolbe Elizabeth , Stafford Charles 
Published: February 2020

Abstract
A multiresidue method was developed and validated for the determination of 13 neonicotinoid pesticides and metabolites, and nine macrocyclic lactone pesticides and veterinary drugs using SPE and ultra-performance liquid chromatography/MS/MS. The method was validated in milk, orange, spinach, apple, plum, watermelon, green bean, zucchini, broccoli, strawberry, grape, and tomato by analyzing replicates of residue-free control samples fortified with a mixture of 22 target analytes at three concentration levels. The recoveries of the analytes from the fortified matrixes were mostly within 70120, except for some of the neonicotinoid metabolites. The LOD values varied by analyte and matrix and ranged between 0.0012 ng/g. The developed method was successful in combining two widely different classes of compounds into a single analysis.
Determination of Residual Carbamate, Organophosphate, and Phenyl Urea Pesticides in Drinking and Surface Water by High-Performance Liquid Chromatography/Tandem Mass Spectrometry
Authors: Hao Chunyan , Nguyen Bick , Zhao Xiaoming , Chen Ernie , Yang Paul 
Published: February 2020

Abstract
Methods using SPE followed by HPLC/MS/MS analysis were developed and validated for the determination of 39 pesticides in different aquatic environmental matrixes. The target pesticides included 12 carbamates, 15 organophosphates, and 12 phenyl ureas, out of which 16 are regulated in North America. Method detection limits were in the low ng/L range using the U.S. Environmental Protection Agency's protocol and multiple reaction monitoring (MRM) data acquisition, meeting the regulatory needs in the United States, Canada, and European Union. Isotope-labeled compounds were used as injection internal standards, as well as method surrogates to improve the data quality. QC/QA data (e.g., method recovery and within-run and between-run method precision) derived from multiyear monitoring activities were used to demonstrate method ruggedness. The same QC/QA data also showed that the method exerted no obvious matrix effect on the target analytes. Parameters that affect method performance, such as preservatives, pH values, sample storage time, and sample extract storage time, were also studied in detail. Accredited by the Canadian Association for Laboratory Accreditation and licensed by the Ontario government for drinking water analysis, these methods have been applied to the analysis of drinking water, ground water, and surface water samples collected in the province of Ontario, Canada, to ensure the pristine nature of Ontario's aquatic environment. Using the scheduled MRM (sMRM) data acquisition algorithm, it was demonstrated that sMRM improved the S/N of extracted ion chromatograms by at least two- to six-fold and, therefore, enhanced the short- and long-term instrument precision, demonstrated the ability to offer high throughput multiresidue analysis, and allowed the use of two MRM transitions for each compound to achieve higher confidence for compound identification.
Development of Optimized Extraction Methodology for Cyanogenic Glycosides from Flaxseed (Linum usitatissimum)
Authors: Barthet Véronique J , Bacala Ray 
Published: February 2020

Abstract
A reference method (higher accuracy) and a routine method (higher throughput) were developed for the extraction of cyanogenic glycosides from flaxseed. Conditions of (essentially) complete extraction were identified by comparing grinding methods and extraction solvent composition, and optimizing solvent-to-meal ratio, extraction time, and repeat extraction. The reference extraction method consists of sample grinding using a high-speed impact plus sieving mill at 18 000 rpm with a 1.0 mm sieve coupled with triple-pooled extraction in a sonicating water bath (40C, 30 min) using 75 methanol. The routine method differs by the use of a coffee mill to grind samples and a single extraction. The 70 and 80 methanol solutions were equal and superior to other combinations from 50 to 100 aqueous ethanol or methanol. The extraction efficiencies of the routine method (relative to the reference method) was 87.9 2.0 SD (linustatin) and 87.6 1.9 SD (neolinustatin) using four composite samples that were generated from seeds of multiple cultivars over two crop years and locations across Western Canada. Ground flaxseed was stable after storage at room temperature, refrigeration, or freezing for up to 7 days, and frozen for at least 2 weeks but less than 2 months. Extracts were stable for up to 1 week at room temperature and at least 2 weeks when refrigerated or frozen.
Analysis of Beverages for Hg, As, Pb, and Cd with a Field Portable X-Ray Fluorescence Analyzer
Authors: Anderson David L 
Published: February 2020

Abstract
Analytical capabilities of a handheld X-ray tube analyzer for analysis of beverages were evaluated. Sets of standard solutions for the elements Hg, As, Pb, and Cd were prepared with mass fractions up to 5000 mg/kg. A thirst quencher beverage was spiked with these elements up to mass fractions of 2500 mg/kg. Portions of these solutions were placed in standard X-ray fluorescence (XRF) cells, as well as the original container, and analyzed by using a field portable Innov-X -6000s XRF tube-type analyzer. Uncorrected analyzer output usually yielded qualitative or semiquantitative results for the spiked beverages in X-ray cells. Average correction factors applied to analyzer output yielded accurate (in terms of z-scores) quantitative results for As above 20 mg/kg and qualitative or semiquantitative results for the other elements. Weighted quadratic fit calibrations provided accurate quantitative or semiquantitative results for all elements at levels above 20 mg/kg. The instrument's preset X-ray overlap correction algorithm worked well for the beverage spiked with all four elements. Spiked beverages analyzed through the wall of the original polyethylene terephthalate container produced accurate results within measurement uncertainties after application of container wall correction factors.
Microwave-Assisted Acid Extraction of Selenium from Medicinal Plants Followed by Electrothermal Atomic Absorption Spectrometric Determination
Authors: Kolachi Nida Fatima , Kazi Tasneem Gul , Baig Jameel Ahmed , Kandhro Ghulam Abbas , Khan Sumaira , Afridi Hassan Imran , Kumar Sham , Shah Abdul Qadir 
Published: February 2020

Abstract
A simple and rapid microwave-assisted extraction (MAE) of selenium (Se) from medicinal plants was investigated using different concentrations of nitric acid and hydrochloric acid, sample mass, heating time, microwave energy, and plant particle size. The optimization strategy was carried out using multivariate methodologies. Electrothermal atomic absorption spectrometry was used to determine Se. The accuracy of the optimized procedure was evaluated by using certified reference materials with certified values for Se and a microwave-assisted acid digestion (MD) method for comparative purpose. No significant difference was observed (P &gt; 0.05) when comparing the values obtained by the proposed MAE and MD methods (paired t-test). Under the optimum operating conditions, the LOD obtained from the standard calibration curve was 0.012 g/L for Se. The average RSD of the MAE method varied between 4.05 and 7.53 (n 6). The proposed method was successfully applied for the determination of Se in medicinal plants used as remedies for cancerous and infection diseases.
Selective Preconcentration/Separation of Copper(II), Iron(III), and Lead(II) as Their N-Benzoyl-N,N-Diisobutylthiourea Chelates on Amberlite XAD-16 Resin
Authors: Soylak Mustafa , Kariper I Afsin 
Published: February 2020

Abstract
A preconcentration/separation procedure for copper(II), iron(III), and lead(II) ions has been established for use prior to their flame atomic absorption spectrometric determination. The presented procedure is based on adsorption of analyte ions on Amberlite XAD-16 resin as their N-benzoyl-N,N-diisobutylthiourea chelates. The influence of analytical parameters including pH of the solutions and type of eluent on the recoveries of Cu(II), Fe(III), and Pb(II) ions was investigated. The recoveries of the analytes were generally &gt;95. No interference effects were observed from alkaline, earth alkaline, or transition metals on the recoveries of the studied metals. The LODs based on 3 were 1.9 g/L for Cu, 5.9 g/L for Fe, and 3.1 g/L for Pb. Validation of the procedure was carried out by analyzing standard reference material 1568a (rice flour). The procedure was applied to the determination of analytes in natural water samples.
Tendency for Interlaboratory Precision in the GMO Analysis Method Based on Real-Time PCR
Authors: Kodama Takashi , Kurosawa Yasunori , Kitta Kazumi , Naito Shigehiro 
Published: February 2020

Abstract
The Horwitz curve estimates interlaboratory precision as a function only of concentration, and is frequently used as a method performance criterion in food analysis with chemical methods. The quantitative biochemical methods based on real-time PCR require an analogous criterion to progressively promote method validation. We analyzed the tendency of precision using a simplex real-time PCR technique in 53 collaborative studies of seven genetically modified (GM) crops. Reproducibility standard deviation (SR) and repeatability standard deviation (Sr) of the genetically modified organism (GMO) amount () was more or less independent of GM crops (i.e., maize, soybean, cotton, oilseed rape, potato, sugar beet, and rice) and evaluation procedure steps. Some studies evaluated whole steps consisting of DNA extraction and PCR quantitation, whereas others focused only on the PCR quantitation step by using DNA extraction solutions. Therefore, SR and Sr for GMO amount () are functions only of concentration similar to the Horwitz curve. We proposed SR 0.1971C0.8685 and Sr 0.1478C0.8424, where C is the GMO amount (). We also proposed a method performance index in GMO quantitative methods that is analogous to the Horwitz Ratio.
Stability-Indicating High-Performance Thin-Layer Chromatographic Method for Quantitative Determination of Omeprazole in Capsule Dosage Form
Authors: Jha Preeta , Parveen Rabea , Khan Suroor A , Alam Ozair , Ahmad Sayeed 
Published: February 2020

Abstract
A novel HPTLC method has been developed and validated for quantitative determination of omeprazole (OPZ) in capsule dosage form. The method was validated according to the International Conference on Harmonization guidelines for accuracy, precision, linearity, specificity, and robustness. HPTLC aluminum sheets precoated with silica gel 60F254 were used as the stationary phase and chloroformmethanol (9 + 1) as the mobile phase. The mobile phase was found to give compact bands for OPZ (Rf value of 0.39 0.12) in densitometric analysis in the absorbance mode at 302 nm. The linear regression analysis data for the calibration plots showed good linearity (r2 = 0.997) with respect to peak area in the concentration range 503000 ng/band. The mean values of the slope and intercept were 9.896 0.0753 and 1870.761 16.866, respectively. The method was also applied for stability testing of OPZ in different stress conditions and found to be accurate, linear, precise, robust, specific, and stability indicating. The method proposed can be used for QC and stability testing of different dosage forms such as tablets and capsules, as well as for bulk drug analysis of OPZ.
Using a First-Derivative Spectrophotometric Method for Simultaneous Determination of Fe(II) and Ni(II) in Mineral Vitamins by Interaction with 2,4-Diamino-5-(2-hydroxy-5-nitrophenylazo)benzenesulfonic Acid Sodium Salt in the Presence of Tween 20
Authors: Hashem Elham Y , Seleim Mohamed M , El-Zohry Ahmed M 
Published: February 2020

Abstract
A highly selective and sensitive derivative spectrophotometric method has been developed for the determination of Fe(II) and Ni(II) in different mineral vitamins. The method is based on the formation of binary complexes of Fe(II) and Ni(II) with 2,4-diamino-5-(2-hydroxy-5-nitrophenylazo) benzenesulfonic acid sodium salt (Mordant Brown 33) at pH 5.6 with Tween 20. At max 512 and 493 nm, the molar absorbtivity was 2.09 104 and 0.58 104 L/mol cm for Fe(II) and Ni(II), respectively. Fe(II) can be determined in the range 0.552.79 g/mL in the presence of 2.92 g/mL Ni, and Ni(II) can be determined in the range 1.173.5 g/mL in the presence of 2.79 g/mL Fe(II) in the presence of Tween 20 (4). The detection limits were 9.0 and 15.0 ng/mL for Fe(II) and Ni(II), respectively. The effect of foreign ions was elucidated. The RSD values were, in all instances, less than 1.3. The proposed method was successfully applied for the simultaneous determination of Fe(II) and Ni(II) in different mineral vitamins.
Determination of Carbamazepine and Its Impurities Iminostilbene and Iminodibenzyl in Solid Dosage Form by Column High-Performance Liquid Chromatography
Authors: Džodić Predrag Lj , ivanovi Ljiljana J , Proti Ana D , Zeevi Mira L , Joci Biljana M 
Published: February 2020

Abstract
An accurate and precise RP-HPLC method was developed and validated for the determination of carbamazepine and its impurities iminostilbene and iminodibenzyl in a tablet formulation with fluphenazine as an internal standard. Buffermethanol (50 + 50, v/v) was used as the mobile phase. During validation, specificity, linearity, precision, accuracy, LOD, LOQ, and robustness of the method were tested. The method was proven to be specific against placebo interference. Linearity was evaluated over the concentration range of 100500, 0.050.25, and 0.10.5 g/mL, and the r values were 0.9994, 0.9997, and 0.9979 for carbamazepine, iminostilbene, and iminodibenzyl, respectively. Intraday precision of the method was good, and RSD was below 2 for all analytes. The accuracy of the method ranged from 100.69 to 102.10, 99.76 to 102.66, and 99.26 to 100.08 for carbamazepine, iminostilbene, and iminodibenzyl, respectively. LOD was 0.0125, 0.025, and 0.05 g/mL and LOQ was 0.05, 0.05, and 0.1 g/mL for carbamazepine, iminostilbene, and iminodibenzyl, respectively. Robustness of the method was proven by using a chemometric approach. The method was successfully applied to the analysis of commercially available carbamazepine tablets and showed good repeatability, with RSD below 2.
Stability-Indicating Validated HPLC Method for Simultaneous Determination of Oral Antidiabetic Drugs from Thiazolidinedione and Sulfonylurea Groups in Combined Dosage Forms
Authors: Gumieniczek Anna , Berecka Anna , Komsta ukasz 
Published: February 2020

Abstract
For type 2 diabetes treatment, combinations of drugs from the thiazolidinedione and sulfonylurea groups are now available in the same tablet or capsule. Therefore, a stability-indicating and validated HPLC method was developed for simultaneous determination of pioglitazone, rosiglitazone, and glipizide in combined dosage forms. The examined drugs were subjected to different conditions such as acid and base, temperature, and UV light, and degradation of pioglitazone and glipizide was observed under thermal and acidic stress. However, selectivity of the presented method for pioglitazone, rosiglitazone, and glipizide assay against their degradation products was confirmed. It was also demonstrated to be robust, resisting small deliberate changes in pH of the buffer, flow rate, and percentage of acetonitrile in the mobile phase. The presented method utilizes a LiChrospher RP18 column (125 4.0 mm), acetonitrile in phosphate buffer at pH 4.3 (40 + 60, v/v) as the mobile phase, and UV detection at 225 nm for pioglitazone/glipizide or 245 nm for rosiglitazone/glipizide. The method was validated with respect to linearity, precision, and accuracy. Finally, the elaborated procedure was applied for the QC of pioglitazone/glipizide and rosiglitazone/glipizide mixtures.
Determination of Multiresidue Pesticides in Green Tea by Using a Modified QuEChERS Extraction and Ion-Trap Gas Chromatography/Mass Spectrometry
Authors: Steiniger David , Lu Guiping , Butler Jessie , Phillips Eric , Fintschenko Yolanda 
Published: February 2020

Abstract
The pesticide residues in exported and imported tea products must not exceed the maximum residue limits (MRLs) regulated by the import countries. Tea is a complex matrix that obfuscates the determination of pesticide residues. Many available methods for multiresidue pesticide analysis of tea are time-consuming and require many cleanup steps. The objective of this study was to develop a simple multiresidue method by using a modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and ion-trap GC/MS/MS, which can identify, confirm, and quantify pesticides in complex matrixes. A tea product was homogenized with water, and the pesticides were extracted with acetonitrile containing 1 acetic acid. The extract was subjected to centrifugation, initial cleanup with dispersive SPE (dSPE), solvent exchange, and final cleanup with dSPE. Diethyl-d10-parathion and triphenyl phosphate were used as the internal standard and surrogate, respectively. The final extract was injected into an ITQ 700 gas chromatograph/mass spectrometer. Quantitation of individual pesticides was based on matrix-matched calibration curves with a correlation coefficient of &gt;0.9930 for the 22 pesticides selected for the study. The recoveries of the 22 pesticides ranged from 78 to 115, except those for diazinon (130) and malathion (122), with an average RSD of 8.7. The LOD values of all of the pesticides, except for terbufos, were below the MRLs set by the European Union and Japan.
HPLC, TLC, and First-Derivative Spectrophotometry Stability-Indicating Methods for the Determination of Tropisetron in the Presence of Its Acid Degradates
Authors: Abdel-Fattah Laila S , El-Sherif Zeinab A , Kilani Khadiga M , El-Haddad Dalia A 
Published: February 2020

Abstract
Three stability-indicating assay methods were developed for the determination of tropisetron in a pharmaceutical dosage form in the presence of its degradation products. The proposed techniques are HPLC, TLC, and first-derivative spectrophotometry (1D). Acid degradation was carried out, and the degradation products were separated by TLC and identified by IR, NMR, and MS techniques. The HPLC method was based on determination of tropisetron in the presence of its acid-induced degradation product on an RP Nucleosil C18 column using methanolwateracetonitriletrimethylamine (65 + 20 + 15 + 0.2, v/v/v/v) mobile phase and UV detection at 285 nm. The TLC method was based on the separation of tropisetron and its acid-induced degradation products, followed by densitometric measurement of the intact spot at 285 nm. The separation was carried out on silica gel 60 F254 aluminum sheets using methanolglacial acetic acid (22 + 3, v/v) mobile phase. The 1D method was based on the measurement of first-derivative amplitudes of tropisetron in H2O at the zero-crossing point of its acid-induced degradation product at 271.9 nm. Linearity, accuracy, and precision were found to be acceptable over concentration ranges of 40240 g/mL, 110 g/spot, and 636 g/mL for the HPLC, TLC, and 1D methods, respectively. The suggested methods were successfully applied for the determination of the drug in bulk powder, laboratory-prepared mixtures, and a commercial sample.
Development and Validation of an HPLC/MS/MS Method for Determining the Thiazolidinone PG15 in Rat Plasma
Authors: UchôA FláVia D T , Palma Eduardo C , Souza Natalia F , Lima Maria C A , Galdino Suely L , Pitta Ivan R , Costa Teresa Dalla 
Published: February 2020

Abstract
A rapid, sensitive, and simple HPLC/MS/MS method was developed and validated for the determination of (5Z,E)-3-[2-(4-chlorophenyl)-2-oxoethyl]-5-(1H-indol-3-ylmethylene)-thiazolidine-2, 4-dione (PG15) in rat plasma using chlortalidone as an internal standard (IS). Analyses were performed using a C18 column and isocratic elution with acetonitrilewater (90 + 10, v/v) containing 10 mM ammonium hydroxide (pH 8.0) as the mobile phase pumped at 0.3 mL/min. Detection was performed by MS with negative ion mode electrospray ionization. Rat plasma samples were prepared by deproteinizing with acetonitrile. Detected fragments were 395.1 &gt; 171.9 for PG15 and 337.3 &gt; 189.9 for the IS. Calibration curves were linear from 10 to 1000 ng/mL, with the determination coefficient &gt;0.99. The intraday and interday precisions were less than 12.2 and 11.3, respectively. The applicability of the HPLC/MS/MS method for pharmacokinetic studies was tested using plasma samples obtained after oral administration of PG15 to rats, and it provided the necessary sensitivity, linearity, precision, accuracy, and specificity.
Determination of Chlorantraniliprole Residues in Crops by Liquid Chromatography Coupled with Atmospheric Pressure Chemical Ionization Mass Spectrometry/Mass Spectrometry
Authors: Grant Joann , Rodgers Carol A , Chickering Clark D , Hill Sidney J , Stry James J 
Published: February 2020

Abstract
An analytical method is presented for the determination of chlorantraniliprole residues in crops. Chlorantraniliprole residues were extracted from crop matrixes with acetonitrile after a water soak. The extracts were passed through a strong anion-exchange (SAX) SPE cartridge stacked on top of a reversed-phase (RP) polymer cartridge. After both cartridges were rinsed and vacuum-dried, the SAX cartridge was removed, and chlorantraniliprole was eluted from the RP polymer cartridge with acetonitrile. The acetonitrile eluate was evaporated to dryness, reconstituted, and analyzed using an LC/MS/MS instrument equipped with an atmospheric pressure chemical ionization source. The method was successfully validated at 0.010, 0.10, and 10 mg/kg for the following crop matrixes: potatoes, sugar beets (tops), lettuce, broccoli, soybeans, soybean forage, tomatoes, cucumbers, oranges, apples, pears, peaches, almonds (nutmeat), rice grain, wheat grain, wheat hay, corn stover, alfalfa forage, cottonseed, grapes, and corn grain. The average recoveries from all crop samples fortified at the method LOQ ranged from 91 to 108, with an overall average recovery of 97. The average recoveries from all crop samples fortified at 10 times the method LOQ ranged from 89 to 115, with an overall average recovery of 101. For all of the fortified control samples analyzed in this study, the overall average recovery was 99.