bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simultaneous Determination of Atorvastatin Calcium and Ramipril in Capsule Dosage Forms by High-Performance Liquid Chromatography and High-Performance Thin Layer Chromatography
Authors: Panchal Hiral J , Suhagia Bhanubhai N 
Published: February 2020

Abstract
Two simple and accurate methods to determine atorvastatin calcium and ramipril in capsule dosage forms were developed and validated using HPLC and HPTLC. The HPLC separation was achieved on a Phenomenex Luna C18 column (250 ⨯ 4.6 mm id, 5 µm) in the isocratic mode using 0.1% phosphoric acidacetonitrile (38 + 62, v/v), pH 3.5 ± 0.05, mobile phase at a flow rate of 1 mL/min. The retention times were 6.42 and 2.86 min for atorvastatin calcium and ramipril, respectively. Quantification was achieved with a photodiode array detector set at 210 nm over the concentration range of 0.5-5 µg/mL for each, with mean recoveries (at three concentration levels) of 100.06 ± 0.49% and 99.95 ± 0.63% RSD for atorvastatin calcium and ramipril, respectively. The HPTLC separation was achieved on silica gel 60 F254 HPTLC plates using methanolbenzeneglacial acetic acid (19.6 + 80.0 + 0.4, v/v/v) as the mobile phase. The Rf values were 0.40 and 0.20 for atorvastatin calcium and ramipril, respectively. Quantification was achieved with UV densitometry at 210 nm over the concentration range of 50500 ng/spot for each, with mean recoveries (at three concentration levels) of 99.98 ± 0.75% and 99.87 ± 0.83% RSD for atorvastatin calcium and ramipril, respectively. Both methods were validated according to International Conference on Harmonization guidelines and found to be simple, specific, accurate, precise, and robust. The mean assay percentages for atorvastatin calcium and ramipril were 99.90 and 99.55% for HPLC and 99.91 and 99.47% for HPTLC, respectively. The methods were successfully applied for the determination of atorvastatin calcium and ramipril in capsule dosage forms without any interference from common excipients.
Determination of Calcium, Magnesium, Sodium, and Potassium in Foodstuffs by Using a Microsampling Flame Atomic Absorption Spectrometric Method After Closed-Vessel Microwave Digestion: Method Validation
Authors: Chekri Rachida , Noël Laurent , Vastel Christelle , Millour Sandrine , Kadar Ali , GuÉrin Thierry 
Published: February 2020

Abstract
This paper describes a validation process in compliance with the NF/EN ISO/IEC 17025 standard for the determination of the macrominerals calcium, magnesium, sodium, and potassium in foodstuffs by microsampling with flame atomic absorption spectrometry after closed-vessel microwave digestion. The French Standards Commission (Agence Francaise de Normalisation) standards NF V03-110, NF EN V03-115, and XP T-90-210 were used to evaluate this method. The method was validated in the context of an analysis of the 1322 food samples of the second French Total Diet Study (TDS). Several performance criteria (linearity, LOQ, specificity, trueness, precision under repeatability conditions, and intermediate precision reproducibility) were evaluated. Furthermore, the method was monitored by several internal quality controls. The LOQ values obtained (25, 5, 8.3, and 8.3 mg/kg for Ca, Mg, Na, and K, respectively) were in compliance with the needs of the TDS. The method provided accurate results as demonstrated by a repeatability CV (CVr) of &lt;7 and a reproducibility CV (CVR) of &lt;12 for all the elements. Therefore, the results indicated that this method could be used in the laboratory for the routine determination of these four elements in foodstuffs with acceptable analytical performance.
Genotyping of Francisella tularensis, the Causative Agent of Tularemia
Authors: Johansson Anders , Petersen Jeannine M 
Published: February 2020

Abstract
Francisella tularensis is a facultative, intracellular, zoonotic pathogen and the causative agent of tularemia. Historically, F. tularensis has been subdivided into subspecies on the basis of phenotypic traits, including biochemical reactivity and virulence. More recently, a number of genotypic methods, ranging from relatively insensitive methods to full genome sequencing, have been used to investigate genetic diversity within F. tularensis. These analyses indicate that F. tularensis is a pathogen of low sequence diversity with pair-wise average nucleotide identities &gt;99.2 across subspecies. Nonetheless, genomic rearrangements and sequence deletions exist between and within F. tularensis subspecies, creating polymorphisms detectable by genotyping methods. Genetic subpopulations intermediate to the subspecies and strain level have been identified within F. tularensis subsp. tularensis and F. tularensis subsp. holarctica by several different typing methods. These genetic subpopulations have been associated with differences in disease severity, geographic distribution, and transmission patterns. For example, one F. tularensis subsp. tularensis subpopulation has been found to be significantly associated with mortality in humans. Additionally, genotypic analyses of Francisella spp. have provided information for use in the rational design of strain panels for validation of F. tularensis diagnostic tests. This review provides a guide to the various F. tularensis genotyping methods.
Analysis of Acrylonitrile, 1,3-Butadiene, and Related Compounds in Acrylonitrile-Butadiene-Styrene Copolymers for Kitchen Utensils and Children's Toys by Headspace Gas Chromatography/Mass Spectrometry
Authors: Ohno Hiroyuki , Kawamura Yoko 
Published: February 2020

Abstract
A headspace gas chromatography/mass spectrometry method was developed for the simultaneous determination of the residual levels of acrylonitrile (AN), 1,3-butadiene (1,3-BD), and their related compounds containing propionitrile (PN) and 4-vinyl-1-cyclohexene (4-VC) in acrylonitrilebutadiene-styrene (ABS) copolymers for kitchen utensils and children's toys. A sample was cut into small pieces, then N,N-dimethylacetamide and an internal standard were added in a sealed headspace vial. The vial was incubated for 1 h at 90C and the headspace gas was analyzed by gas chromatography/mass spectrometry. The recovery rates of the analytes were 93.3101.8 and the coefficients of variation were 0.36.5. In ABS copolymers, the levels were 0.350.4 g/g for AN, ND4.5 g/g for PN, 0.061.58 g/g for 1,3-BD, and 1.1295 g/g for 4-VC. The highest level was found for 4-VC, which is a dimer of 1,3-BD, and the next highest was for AN, which is one of the monomers of the ABS copolymer. Furthermore, the method was also applied to acrylonitrile-styrene (AS) copolymers and polystyrenes (PS) for kitchen utensils, and nitrile-butadiene rubber (NBR) gloves. In AS copolymers, AN and PN were detected at 16.854.5 and 0.86.9 g/g, respectively. On the other hand, the levels in PS and NBR samples were all low.
RP-HPLC Method for Simultaneous Determination of Butenafine Hydrochloride and Betamethasone Dipropionate in a Cream Formulation
Authors: Bhosale Suryakant D , Rajput Sadhana J 
Published: February 2020

Abstract
An RP-HPLC method has been developed for the simultaneous determination of butenafine hydrochloride and betamethasone dipropionate on an Inertsil C18 column (250×4.6 mm id) using a mobile phase gradient consisting of methanol and water at a flow rate of 1 mL/min. Detection was carried out at 254 nm. Retention times of betamethasone dipropionate and butenafine hydrochloride were 4.82 (±0.80) and 16.18 (±0.17) min, respectively. The method was validated with respect to specificity, linearity, accuracy, precision, ruggedness, and robustness. This method is simple, precise, and sensitive, and applicable for the simultaneous quantification of butenafine hydrochloride and betamethasone dipropionate in a cream formulation.
Determination of Arsenic in Scalp Hair Samples from Exposed Subjects Using Microwave-Assisted Digestion With and Without Enrichment Based on Cloud Point Extraction by Electrothermal Atomic Absorption Spectrometry
Authors: Kazi Tasneem Gul , Baig Jameel Ahmad , Shah Abdul Qadir , Kandhro Ghulam Abbas , Khan Sumaira , Afridi Hassan Imran , Kolachi Nida Fatima , Wadhwa Sham Kumar , Shah Faheem , Baig Akhtar Mehmood 
Published: February 2020

Abstract
A simple and rapid cloud point extraction (CPE) procedure was applied for preconcentration of trace quantities of arsenic (As) in scalp hair samples. The samples were subjected to microwave-assisted digestion in a mixture of nitric acid and hydrogen peroxide (2 + 1, v/v) prior to preconcentration by CPE. The As in digested samples was complexed with ammonium pyrrolidine dithiocarbamate (APDC), and the resultant As-PDC complex was extracted by a nonionic surfactant, octylphenoxypolyethoxyethanol (Triton X-114). After centrifugation, the surfactant-rich phase was diluted with 0.1 M HNO3 in methanol and analyzed by electrothermal atomic absorption spectrometry. The experimental parameters, i.e., amount of APDC, concentration of Triton X-114, equilibrium temperature and time, were optimized. For validation of the proposed method, a certified reference material (CRM) of human hair (BCR 397) was used. No significant difference (P&gt;0.05) was observed between the experimental results and certified values of the CRM (paired t-test). The LOD and LOQ obtained under the optimal conditions were 0.025 and 0.083 μg/kg, respectively. The developed method was applied for the determination of As in scalp hair samples from male and female subjects of two villages of Khairpur Mir's, Pakistan.
Resolution and Quantification of Isomeric Fatty Acids by Silver Ion HPLC: Fatty Acid Composition of Aniseed Oil (Pimpinella anisum, Apiaceae)
Authors: Denev Roumen V , Kuzmanova Ivalina S , Momchilova Svetlana M , Nikolova-Damyanova Boryana M 
Published: February 2020

Abstract
A silver ion HPLC procedure is described that is suitable to determine the fatty acid composition of plant seed oils. After conversion of fatty acids to p-methoxyphenacyl derivatives, it was possible to achieve baseline resolution of all fatty acid components with 0 to 3 double bonds, including the positionally isomeric 18:1 fatty acids oleic acid (cis 9-18:1), petroselinic acid (cis 6-18:1), and cis-vaccenic acid (cis 11-18:1), in aniseed oil (Pimpinella anisum, Apiaceae) by a single gradient run on a single cation exchange column laboratory converted to the silver ion form. The UV detector response (280 nm) was linearly related to the fatty acid concentration in the range 0.01 to 3.5 mg/mL.
European Analytical Criteria: Past, Present, and Future
Authors: Vanhaecke Lynn , Gowik Petra , Bizec Bruno Le , Ginkel Leen Van , Bichon Emmanuelle , Blokland Marco , Brabander Hubert F De 
Published: February 2020

Abstract
In this paper, the past, present, and (possible) future of the European analytical criteria for residues are described. The elaboration of the revision of Commission Decision 93/256/EC was a long process starting in 1996 and ending with the formation of a European Commission (EC) working group in 1998. This working group took account of developments in scientific and technical knowledge at that time and produced a draft version of the revision within 6 months. The revision, finally published in 2002 (2002/657/EC), includes new ideas on the identification of analytes and the criteria for performance assessment as well as validation procedures. Currently (2009), the evolution in analytical equipment and progress in scientific research, accompanied by recent European regulatory changes, demands an update or revision of the 2002/657/EC.
Validation of the Charm MRL-3 for Fast Screening of -Lactam Antibiotics in Raw Milk
Authors: Reybroeck Wim , Ooghe Sigrid , Brabander Hubert F De , Daeseleire Els 
Published: February 2020

Abstract
The biochemicals utilized in the Charm MRL -Lactam test (8 min test) were applied to faster flowing lateral components to create a new 3 min, one-step -lactam test called Charm MRL-3 (Charm Sciences Inc., Lawrence, MA). This new test was validated at T&V-ILVO according to Commission Decision 2002/657/EC. The following analytical parameters were checked: test specificity, detection capability, and test robustness (impact of deviation of the test protocol, and impact of the milk composition, batch differences of reagents). Further, the suitability of the Charm MRL-3 to screen heat-treated milk or milk from animal species other than the cow was also tested. Finally, the test was integrated in the monitoring of dairy samples to check the occurrence of false-negative or false-positive results, and the test was also included in a national ring trial and an international proficiency study. The results proved that the Charm MRL-3 is a fast, simple, and reliable cows' milk test that can be used at the farm level in order to prevent tanker milk contamination, or at the entrance of the dairy plant to screen tanker milk for the presence of -lactam antibiotics.
Chemometric Methods for the Simultaneous Determination of Some Water-Soluble Vitamins
Authors: Mohamed Abdel-Maaboud I , Mohamed Horria A , Mohamed Niveen A , El-Zahery Marwa R 
Published: February 2020

Abstract
Two spectrophotometric methods, derivative and multivariate methods, were applied for the determination of binary, ternary, and quaternary mixtures of the water-soluble vitamins thiamine HCl (I), pyridoxine HCl (II), riboflavin (III), and cyanocobalamin (IV). The first method is divided into first derivative and first derivative of ratio spectra methods, and the second into classical least squares and principal components regression methods. Both methods are based on spectrophotometric measurements of the studied vitamins in 0.1 M HCl solution in the range of 200500 nm for all components. The linear calibration curves were obtained from 2.590 g/mL, and the correlation coefficients ranged from 0.9991 to 0.9999. These methods were applied for the analysis of the following mixtures: (I) and (II); (I), (II), and (III); (I), (II), and (IV); and (I), (II), (III), and (IV). The described methods were successfully applied for the determination of vitamin combinations in synthetic mixtures and dosage forms from different manufacturers. The recovery ranged from 96.1 1.2 to 101.2 1.0 for derivative methods and 97.0 0.5 to 101.9 1.3 for multivariate methods. The results of the developed methods were compared with those of reported methods, and gave good accuracy and precision.
Validation of a Capillary Electrophoresis Method for the Simultaneous Determination of Amlodipine Besylate and Valsartan in Pharmaceuticals and Human Plasma
Authors: Alnajjar Ahmed O 
Published: February 2020

Abstract
A rapid, simple, and sensitive capillary electrophoresis (CE) method was developed and validated for the simultaneous determination of amlodipine (AML) and valsartan (VAL) in pharmaceuticals and human plasma using a UV photodiode array detector. Electrophoretic conditions were optimized to improve separation, sensitivity, and rapidity. The optimal conditions were 25 mM phosphate buffer at pH 8.0, injection time 10.0 s, voltage 25 kV, and column temperature 25C, with detection at 214 nm. The method was found to be linear in the range of 1.035 and 1.0350 mg/L, with weighted regression 0.9999 and 0.9994, for AML and VAL, respectively. Validation of the method showed acceptable intraday and interday accuracy (85.595.3) and precision (RSD 1.644.2) in pharmaceutical formulation and human plasma analysis. The sensitivity of the method was enhanced by both optimization of the CE procedure and preconcentration performed by liquidliquid extraction. The LOD for both AML and VAL was 0.03 mg/L, which allows analysis at the level of the drugs possibly found in human plasma. Therefore, the proposed method is suitable for QC in pharmaceutical laboratories and therapeutic drug monitoring in clinical laboratories.
Aqueous Sulfuric Acid as the Mobile Phase in Cation Ion Chromatography for Determination of Histamine, Putrescine, and Cadaverine in Fish Samples
Authors: Liao Benjamin S , Sram Jackie , Cain Teresa T , Halcrow Kenneth R 
Published: February 2020

Abstract
Aqueous sulfuric acid can be used as the mobile phase in cation ion chromatography to separate the three biogenic amines, putrescine, cadaverine, and histamine, from fish. Various concentrations of aqueous sulfuric acid were investigated to optimize the separation of these three biogenic amines. Aqueous sulfuric acid (5.0 mM) was found to be optimum for the separation and was used to determine the three biogenic amines in fish. The LOQ, defined as the lowest level of the standard calibration curve, was 0.055 ppm (equivalent to 0.55 g/g sample) for putrescine, 0.05 ppm (equivalent to 0.5 g/g sample) for cadaverine, and 1.0 ppm (equivalent to 10 g/g sample) for histamine. From statistical analysis of the LOQ, the method detection limit was 0.003 ppm for putrescine, 0.009 ppm for cadaverine, and 0.16 ppm for histamine. For sample preparation, the fish was composited, homogenized in methanolwater (75 25, v/v), incubated for 15 min at 60C, and centrifuged. The sample solution was micron-filtered before injection. The mobile phase flow rate was 0.8 mL/min under isocratic conditions at room temperature (1525C). The three biogenic amines were separated in the order of increasing retention time, i.e., putrescine, cadaverine, and histamine, within 30 min. The chromatograms showed complete peak separation of the three amines regardless of the difference in fish matrixes.
Determination of Neomycin and Oxytetracycline in the Presence of Their Impurities in Veterinary Dosage Forms by High-Performance Liquid Chromatography/Tandem Mass Spectrometry
Authors: Vučičevič-Prčetič Katarina , Cservenák Robert , Radulović Niko 
Published: February 2020

Abstract
Two HPLC/MS/MS methods, one for determination of neomycin sulfate and the other for determination of oxytetracycline hydrochloride in the presence of their impurities, were developed and validated. Separations were achieved with gradient elution on a C18 column. All components were ionized by positive-ion electrospray and detected by multiple reaction monitoring. Calibration curves were linear, with correlation coefficients &gt;0.99. Precision of the methods was confirmed by RSD values of 0.34 and 0.71% for neomycin and oxytetracycline, respectively. Recovery values of 101.5 and 101.0%, respectively, indicated adequate accuracy. Analysis time for neomycin was 24 min, with the retention time of the main compound at 10.1 min; for oxytetracycline, the analysis time was 18 min, with the main peak at 9.95 min. Longer retention times than expected were a consequence of the necessity of chromatographic separation of isomers with the same ion transition. All impurities defined in the pharmacopoeias were determined and their identities confirmed. The methods were tested for QC of veterinary dosage forms (commercial powders and injections containing these antibiotics).
Development of Quality Assessment Method for Optically Active Food Flavor Chemicals
Authors: Saito Koichi , Hosono Kouhei , Kitazawa Nariko , Iwasaki Yusuke , Ito Rie , Nakazawa Hiroyuki 
Published: February 2020

Abstract
A quality assessment method for commercially available, optically active flavor compounds, namely, menthol, menthyl acetate, borneol, perillaldehyde, and 1,8-cineol, was developed. A gas chromatograph equipped with a flame ionization detector and a DB-5ms capillary column was used for the chemical purity test. A GC/MS with a β-DEX cyclodextrin column was used for the optical purity test, by which the enantiomeric separation of each flavor compound was achieved. Enantiomeric excess was calculated as an expression of optical purity. Of the 25 standard samples subjected to the chemical purity test, six were found to have lower purity than the data provided by the manufacturers. When the same samples were subjected to the optical purity test, 11 were found to have lower purity than that indicated on the reagent labels. These results suggest that there is a need to conduct an optical purity test, in addition to a chemical purity test, for the quality assessment of flavor standards.
Analysis of Pesticides Residues in Fresh Produce Using Buffered Acetonitrile Extraction and Aminopropyl Cleanup with Gas Chromatography/Triple Quadrupole Mass Spectrometry, Liquid Chromatography/Triple Quadrupole Mass Spectrometry, Gas Chromatography/Ion Trap Detector Mass Spectrometry, and GC with a Halogen-Specific Detector
Authors: Brown Amy N , Cook Jo Marie , Hammack Walter T , Stepp Jason S , Pelt Jonathan V , Gerard Ghislain 
Published: February 2020

Abstract
A rapid and inexpensive multiresidue method for determining pesticides in fruits and vegetables is presented. Extraction of a 15 g sample with 15 mL acetonitrile was followed by buffering with magnesium sulfate, sodium chloride, sodium citrate dihydrate, and disodium citrate. Acidification with formic acid prior to dispersive cleanup with aminopropyl sorbent and magnesium sulfate was used to stabilize base-sensitive pesticides such as chlorothalonil. Extracts were concentrated to 2 g/mL. Analyses were conducted by GC/ion trap detector MS, GC-halogen-specific detector, and LC/triple quadrupole MS. Accuracy and repeatability for 166 compounds in tomato, potato, and cabbage were 70–120% and &lt;20% CV in 85% of the compounds, respectively. Reproducibility over a 4 month period in multiple commodities and analytical conditions was 62–124%, with CVs better than 30% for 91% of the compounds. Supply cost/sample was reduced 66%, and time to extract a batch of 24 samples was reduced by half compared to the prior method that used a 50 g sample, 100 mL acetonitrile, multiple SPE columns, and additional instrumentation. Additional extraction studies were conducted in tomatoes, oranges, and green beans at 4 g/mL using a GC/MS triple quadrupole system with a programmable temperature vaporization inlet. Recoveries of 70–120% were achieved in 93% of all compounds in green beans, 95% in tomatoes, and 97% in oranges.
Application of a Liquid Chromatography Tandem Mass Spectrometry Method for the Simultaneous Detection of Seven Allergenic Foods in Flour and Bread and Comparison of the Method with Commercially Available ELISA Test Kits
Authors: Heick Julia , Fischer Markus , Kerbach Sandra , Tamm Ulrike , Popping Bert 
Published: February 2020

Abstract
To protect the allergic consumer, analytical methods need to be capable of detecting allergens in fnished products that typically contain multiple allergens. An LC/MS/MS method for simultaneous detection of seven allergens was developed and compared with commercially available ELISA kits. The detection capabilities of this novel method were demonstrated by analyzing incurred material containing milk, egg, soy, peanut, hazelnut, walnut, and almond. Bread was chosen as a model matrix. To assess the inﬂuence of baking on the method’s performance, analysis was done before and after baking. The same samples were analyzed with ELISA test kits from ELISA Systems, Morinaga, Neogen, and r-Biopharm. Peanut, hazelnut, walnut, and almond could be detected with both ELISA and LC/MS/MS regardless of whether the product was baked or not. LC/MS/MS clearly showed superior detection of milk in processed matrixes compared to ELISA, which exhibited signifcantly lower sensitivities when analyzing the baked products. Similar results were obtained when analyzing egg; however, one kit was capable of detecting egg in the processed samples as well.