bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development and Validation of a High-Performance Liquid Chromatographic Method for Determination of Eprosartan in Bulk Drug and Tablets
Authors: Patel Harsha U , Suhagia Bhanubhai N , Patel Chhaganbhai N 
Published: February 2020

Abstract
A simple, precise, and accurate isocratic RP-HPLC method was developed and validated for determination of eprosartan in bulk drug and tablets. Isocratic RP-HPLC separation was achieved on a Phenomenex C18 column (250 4.6 mm id, 5 m particle size) using the mobile phase 0.5 formic acidmethanolacetonitrile (80 25 20, v/v/v, pH 2.80) at a flow rate of 1.0 mL/min. The retention time of eprosartan was 7.64 0.05 min. The detection was performed at 232 nm. The method was validated for linearity, precision, accuracy, robustness, solution stability, and specificity. The method was linear in the concentration range of 10400 g/mL with a correlation coefficient of 0.9999. The repeatability for six samples was 0.253 RSD; the intraday and interday precision were 0.210.57 and 0.330.71 RSD, respectively. The accuracy (recovery) was found to be in the range of 99.86100.92. The drug was subjected to the stress conditions hydrolysis, oxidation, photolysis, and heat. Degradation products produced as a result of the stress conditions did not interfere with detection of eprosartan; therefore, the proposed method can be considered stability-indicating.
Simultaneous Determination of Antazoline and Naphazoline by the Net Analyte Signal Standard Addition Method and Spectrophotometric Technique
Authors: Asadpour-Zeynali Karim , Ghavami Raoof , Esfandiari Roghayeh , Soheili-Azad Payam 
Published: February 2020

Abstract
A novel net analyte signal standard addition method (NASSAM) was used for simultaneous determination of the drugs anthazoline and naphazoline. The NASSAM can be applied for determination of analytes in the presence of known interferents. The proposed method is used to eliminate the calibration and prediction steps of multivariate calibration methods; the determination is carried out in a single step for each analyte. The accuracy of the predictions against the H-point standard addition method is independent of the shape of the analyte and interferent spectra. The net analyte signal concept was also used to calculate multivariate analytical figures of merit, such as LOD, selectivity, and sensitivity. The method was successfully applied to the simultaneous determination of anthazoline and naphazoline in a commercial eye drop sample.
Evaluation of Preservative Effectiveness of Liquid Crystalline Systems with Retynil Palmitate by the Challenge Test and D-value
Authors: Chorilli Marlus , Leonardi Gislaine Ricci , Nunes Salgado Hérida Regina , Scarpa Maria Virgínia 
Published: February 2020

Abstract
The objective of this work was to evaluate the preservative effectiveness of liquid crystalline systems containing retynil palmitate (RP) by the challenge test (CT) and D-value. A system was developed containing water, silicon glycol copolymer, and polyether functional siloxane with 1% RP added. The analyses were carried out by methods in the U.S. Pharmacopeia (USP 31, 2008) using the microorganisms Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Aspergillus niger. The CT showed that after 7 days, all microorganisms were eliminated except A. niger, which maintained viability for at least 28 days after inoculation. Moreover, the microorganisms E. coli, P. aeruginosa, S. aureus, C. albicans and A. niger presented different growth behaviors, evidenced by differences among the D-values calculated. It was concluded that the CT and D-value were efficient methods for evaluation of the preservative property of these formulations.
Synchronous High-Performance Liquid Chromatography with a Photodiode Array Detector and Mass Spectrometry for the Determination of Citrinin, Monascin, Ankaflavin, and the Lactone and Acid Forms of Monacolin K in Red Mold Rice
Authors: Wu Cheng-Lun , Kuo Yao-Haur , Lee Chun-Lin , Hsu Ya-Wen , Pan Tzu-Ming 
Published: February 2020

Abstract
The Monascus fermentation product red mold rice (RMR) has been found to contain the cholesterol-lowering agent monacolin K (MK) in both its lactone (MKL) and acid (MKA) forms and the mycotoxin citrinin (CT). The yellow pigments in RMR, namely, monascin (MS) and ankaflavin (AK), have been reported to exhibit antimetastatic and antiangiogenic activities. Currently, MK and these yellow pigments are usually detected in RMR by different analytical methods that are inconvenient, expensive, and time-consuming. The goal of this study was to establish a rapid, synchronous analytical method for determination of the MKA, MKL, MS, AK, and CT levels in RMR. MKA, MKL, MS, AK, and CT were extracted by the same extraction method, then separated by RP-HPLC with a C18 column. The effluent from the column was passed through a photodiode array detector and then introduced directly into a fluorescence detector. The results showed that high recovery rates of MKA, MKL, MS, AK, and CT are possible if RMR powder is extracted with 75% ethanol (10 mL) at 80°C for 30 min. With regard to the optimal conditions of the HPLC, the peaks of MKA, MKL, MS, AK, and CT can be clearly separated from any noise peaks by isocratic elution with a mobile phase comprising 0.05% trifluoroacetic acid in acetonitrile–water (62.5 + 37.5, v/v).
A Single-Laboratory Validated Method for the Generation of DNA Barcodes for the Identification of Fish for Regulatory Compliance
Authors: Handy Sara M , Deeds Jonathan R , Ivanova Natalia V , Hebert Paul D N , Hanner Robert H , Ormos Andrea , Weigt Lee A , Moore Michelle M , Yancy Haile F 
Published: February 2020

Abstract
The U.S. Food and Drug Administration is responsible for ensuring that the nation's food supply is safe and accurately labeled. This task is particularly challenging in the case of seafood where a large variety of species are marketed, most of this commodity is imported, and processed product is difficult to identify using traditional morphological methods. Reliable species identification is critical for both foodborne illness investigations and for prevention of deceptive practices, such as those where species are intentionally mislabeled to circumvent import restrictions or for resale as species of higher value. New methods that allow accurate and rapid species identifications are needed, but any new methods to be used for regulatory compliance must be both standardized and adequately validated. "DNA barcoding" is a process by which species discriminations are achieved through the use of short, standardized gene fragments. For animals, a fragment (655 base pairs starting near the 5′ end) of the cytochrome c oxidase subunit 1 mitochondrial gene has been shown to provide reliable species level discrimination in most cases. We provide here a protocol with single-laboratory validation for the generation of DNA barcodes suitable for the identification of seafood products, specifically fish, in a manner that is suitable for FDA regulatory use.
Disposable Screen-Printed Electrode Coupled with Recombinant Drosophila melanogaster Acetylcholinesterase and Multiwalled Carbon Nanotubes for Rapid Detection of Pesticides
Authors: Tang Zhuzhao , Chen Haode , Song Shiping , Fan Chunhai , Zhang Dabing , Wu Aibo 
Published: February 2020

Abstract
Recombinant Drosophila melanogaster acetylcholinesterase (R-DmAChE), multiwalled carbon nanotubes (MWCNTs), and Prussian blue have been combined for development of a three-electrode biosensor with more rapid responses and higher stability than in our previous study. A new disposable screen-printed electrode (SPE) was developed for rapid detection of organophosphate and carbamate pesticides. After optimization, 10 μg MWCNT and 5 μL enzyme immobilization solution consisting of 0.2% glutaraldehyde, 0.1% Nafion®, 0.2% bovine serum albumin, 0.1 g/L MWCNT, and 1.5 mU R-DmAChE were fixed on each of the R-DmAChE/MWCNT SPEs. The LOD of this biosensor was 0.5 μg/L for pesticide standards of dichlorvos (DDV) and carbofuran. The performance of this biosensor was tested for vegetable and water samples at various spiked levels, and good stability and sensitivity were found. The obtained recoveries were from 82.6 to 110.5% for DDV at levels of 0.5–5 μg/L and 73.4 to 118.4% for carbofuran at 1–10 μg/L in lake and sea water samples, demonstrating that the proposed approach is an alternative means for rapid detection of pesticide residues and contaminants in food safety and environmental monitoring.
Development of a Quantitative Multiclass/Multiresidue Method for 21 Veterinary Drugs in Shrimp
Authors: Li Hui , Kijak Philip J 
Published: February 2020

Abstract
A multiclass/multiresidue method has been developed and validated for the determination of 21 veterinary drug residues in shrimp, including sulfonamides (sulfadiazine, sulfamerazine, sulfamethazine, sulfachloropyridazine, sulfadimethoxine, and sulfaquinoxaline); tetracyclines (oxytetracycline, tetracycline, and chlortetracycline); (fluoro)quinolones (norfloxacin, ciprofloxacin, enrofloxacin, sarafloxacin, difloxacin, flumequine, oxolinic acid, and nalidixic acid); and cationic dyes (malachite green, gentian violet, leucomalachite green, and leucogentian violet), using HPLC/MS/MS. All drugs were quantifiable over a no less than 10-fold range with matrix-matched standards for linear external calibration, except for oxytetracycline, tetracycline, norfloxacin, and ciprofloxacin, for which norfloxacin-d5 was used as an internal standard. Two grams of preground shrimp sample was extracted twice with extractant at two different pH values. The combined supernatant was further diluted with an aqueous internal standard solution, and 50 L extract was injected into the HPLC instrument. An online SPE system was set up for automated sample cleanup. A triple quadrupole mass spectrometer equipped with an electrospray ionization source was operated in the multiple-reaction-monitoring mode to acquire data. The method has been validated at three levels within the designated linear ranges for each drug, with accuracies between 77 and 115, and most CV values below 15.
Development and Validation of a High-Performance Thin-Layer Chromatographic Method for Determination of Ofloxacin Residues on Pharmaceutical Equipment Surfaces
Authors: Vovk Irena , Simonovska Breda 
Published: February 2020

Abstract
An HPTLC method with densitometric quantification using fluorescence at 313 nm was developed and validated for the determination of ofloxacin residue in controlling pharmaceutical equipment cleanliness. Simulated samples at a residue level of 1 mg/m2 were prepared by spreading the calculated amount of ofloxacin solution on 1, 5, and 10 dm2 stainless steel surfaces. After evaporation of the solvent, the residue was removed by two ethanol wetted cotton swabs, which were thereafter extracted with the mixture of ethanol and Na2EDTA–water solution at pH 11 for 15 min with sonication. The extract and standards were applied on HPTLC silica gel 60 plates and then developed in a horizontal developing chamber from both sides using ethanol-conc. ammonia (4 + 1, v/v) as the mobile phase. The mean recovery (n = 6) at 1 mg/m2 from 1, 5, and 10 dm2 was 95.3, 88.6, and 89.7% with the CV values 3.78, 4.41, and 4.97%, respectively. The absolute detection limit was 0.6 ng and the quantitation limit was 2 ng, but it was shown that these can be improved by immersion of the developed plate into a solution of liquid paraffin–n-hexane (1 + 2, v/v) to approximately 0.25 and 0.9 ng, respectively. The LOD of the method using detection without paraffin–n-hexane was 3, 0.6, and 0.3 μg/m2 by swabbing 1, 5, and 10 dm2, respectively. The method can be applied to routine control of pharmaceutical equipment cleanliness by sampling from stainless steel surface areas of 1 to 10 dm2 with acceptable residue limit/surface of 1 mg/m2.
Advantages of Automation in Plasma Sample Preparation Prior to HPLC/MS/MS Quantification: Application to the Determination of Cilazapril and Cilazaprilat in a Bioequivalence Study
Authors: Kolocouri Filomila , Dotsikas Yannis , Apostolou Constantinos , Kousoulos Constantinos , Soumelas Georgios-Stefanos , Loukas Yannis L 
Published: February 2020

Abstract
An HPLC/MS/MS method characterized by complete automation and high throughput was developed for the determination of cilazapril and its active metabolite cilazaprilat in human plasma. All sample preparation and analysis steps were performed by using 2.2 mL 96 deep-well plates, while robotic liquid handling workstations were utilized for all liquid transfer steps, including liquid–liquid extraction. The whole procedure was very fast compared to a manual procedure with vials and no automation. The method also had a very short chromatographic run time of 1.5 min. Sample analysis was performed by RP-HPLC/MS/MS with positive electrospray ionization using multiple reaction monitoring. The calibration curve was linear in the range of 0.500–300 and 0.250–150 ng/mL for cilazapril and cilazaprilat, respectively. The proposed method was fully validated and proved to be selective, accurate, precise, reproducible, and suitable for the determination of cilazapril and cilazaprilat in human plasma. Therefore, it was applied to a bioequivalence study after per os administration of 2.5 mg tablet formulations of cilazapril.
Determination of Fat-Soluble Vitamins and Carotenoids in Standard Reference Material 3280 Multivitamin/Multielement Tablets by Liquid Chromatography with Absorbance Detection
Authors: Thomas Jeanice B , Sharpless Katherine E , Yen James H , Rimmer Atherine 
Published: February 2020

Abstract
The concentrations of selected fat-soluble vitamins and carotenoids in Standard Reference Material (SRM) 3280 Multivitamin/Multielement Tablets have been determined by two independent LC methods, with measurements performed by the National Institute of Standards and Technology (NIST). This SRM has been prepared as part of a collaborative effort between NIST and the National Institutes of Health Office of Dietary Supplements. The SRM is also intended to support the Dietary Supplement Ingredient Database that is being established by the U.S. Department of Agriculture. The methods used at NIST to determine the concentration levels of vitamins A and E, and β-carotene in the SRM used RPLC with absorbance detection. The relative precision of these methods ranged from 2 to 8% for the analytes measured. SRM 3280 is primarily intended for use in validating analytical methods for the determination of selected vitamins, carotenoids, and elements in multivitamin/multielement tablets and similar matrixes.
Determination of Disulfiram by Micellar Liquid Chromatography in Illicit Preparations
Authors: mourya Sandeep-Kumar , Dubey Swati , Durgabanshi Abhilasha , Kumar Shukla Sudheer , Esteve-Romero Josep , Bose Devasish 
Published: February 2020

Abstract
Presently, disulfram is used in aversion therapy for recovering alcoholics. It acts by inhibiting aldehyde dehydrogenase, leading to high blood levels of acetaldehyde. A simple direct injection micellar liquid chromatographic procedure was developed to determine disulfram in illicit preparations (ayurvedic, herbal, divine ash, and traditional medicine), as well as inpharmaceuticals and biological samples (urine). After application of a predictive optimization strategy, the proposed method was developed using a 0.1 M sodium dodecyl sulfate-butanol 4% (v/v) buffered to pH 7 as the mobile phase at a ﬂow rate of 1 mL/min, an octyl silyl (C8) 150 mm column, and diode array detection at 248 nm. Under the above conditions, the analysis time was below 8 min. Validation studies were based on U.S. Food and Drug Administration guidelines. The LOD (3 × SD criterion) was 15 ng/mL and LOQ (10 × SD criterion) was 70 ng/mL for disulfram. The intraday and interday precisions were below 3.5%, recoveries were in the range of 97–102%, and robustness was below 3%. The optimized and validated micellar liquid chromatographic method was successfully applied to the determination of disulfram in ayurvedic, herbal, divine ash, and other samples. The procedure developed could also be used in the felds of QC, routine analysis, and pharmacokinetic studies.
Development of Standard Method Performance Requirements for Biological Threat Agent Detection Methods
Authors: Coates Scott G , Brunelle Sharon L , Davenport Matthew G 
Published: February 2020

Abstract
Standards and third-party testing are necessary to demonstrate the performance and limitations of biological threat agent (biothreat) detection technologies to allow appropriate response actions by end-users and responders. In order to address this need, the Department of Homeland Security, Science and Technology Directorate has funded AOAC INTERNATIONAL to develop standards and perform conformity assessment. AOAC formed the Stakeholder Panel on Agent Detection Assays to develop consensus performance criteria (standard method performance requirements; SMPRs) for methods that detect biothreats. This paper documents the development of the frst fve biothreat SMPRs, including the voluntary consensus process, the components of an SMPR, the use of SMPRs in developing validation protocols, and a description of the development efforts and considerations for each of the current SMPRs.
Evaluation of Applied Biosystems MicroSEQ® Real-Time PCR System for Detection of Listeria monocytogenes in Food
Authors: Tebbs Robert S , Balachandran Priya , Wong Lily Y , Zoder Patrick , Furtado Manohar R , Petrauskene Olga V , Cao Yanxiang 
Published: February 2020

Abstract
Increasingly, more food companies are relying on molecular methods, such as PCR, for pathogen detection due to their improved simplicity, sensitivity, and rapid time to results. this report describes the validation of a new Real-time PCR method to detect Listeria monocytogenes in nine different food matrixes. the complete system consists of the MicroSEQ®L. monocytogenes Detection Kit, sample preparation, the Applied Biosystems 7500 Fast Real-time PCR instrument, and RapidFinder™ Express software. two sample preparation methods were validated: the PrepSEQ® Nucleic Acid extraction kit and the PrepSEQ Rapid Spin sample preparation kit. the test method was compared to the ISO 11290-1 reference method using an unpaired-study design to detect L. monocytogenes in roast beef, cured bacon, lox (smoked salmon), lettuce, whole cow's milk, dry infant formula, ice cream, salad dressing, and mayonnaise. the MicroSEQ L. monocytogenes Detection Kit and the ISO 11290-1 reference method showed equivalent detection based on Chi-square analysis for all food matrixes when the samples were prepared using either of the two sample preparation methods. An independent validation confirmed these findings on smoked salmon and whole cow's milk. the MicroSEQ kit detected all 50 L. monocytogenes strains tested, and none of the 30 nontargeted bacteria strains.
Modification of the BAX®Salmonella Test Kit to Include a Hot Start Functionality (Modification of AOAC Official MethodSM 2003.09)
Authors: Wallace F Morgan , DiCosimo Deana , Farnum Andrew , Tice George , Andaloro Bridget , Davis Eugene , Burns Frank R 
Published: February 2020

Abstract
In 2010, the BAX® System PCR assay for Salmonella was modified to include a hot start functionality designed to keep the reaction enzyme inactive until PCR begins. To validate the assay's Official Methods of Analysis status to include this procedure modification, an evaluation was conducted on four food types that were simultaneously analyzed with the BAX System and either the U.S. Food and Drug Administration's Bacteriological Analytical Manual or the U.S. Department of Agriculture-Food Safety and Inspection Service Microbiology Laboratory Guidebook reference method for detecting Salmonella. Identical performance between the BAX System method and the reference methods was observed. Additionally, lysates were analyzed using both the BAX System Classic and BAX System Q7 instruments with identical results using both platforms for all samples tested. Of the 100 samples analyzed, 34 samples were positive for both the BAX System and reference methods, and 66 samples were negative by both the BAX System and reference methods, demonstrating 100% correlation. No instrument platform variation was observed. Additional inclusivity and exclusivity testing using the modified test kit demonstrated the test kit to be 100% accurate in evaluation of test panels of 352 Salmonella strains and 46 non-Salmonella strains.
Differential roles of two DDX17 isoforms in the formation of membraneless organelles
Authors: Hirai Yuya , Domae Eisuke , Yoshikawa Yoshihiro , Tomonaga Keizo 
Published: February 2020

Abstract
The RNA helicase, DDX17 is a member of the DEAD-box protein family. DDX17 has two isoforms: p72 and p82. The p82 isoform has additional amino acid sequences called intrinsically disordered regions (IDRs), which are related to the formation of membraneless organelles (MLOs). Here, we reveal that p72 is mostly localized to the nucleoplasm, while p82 is localized to the nucleoplasm and nucleoli. Additionally, p82 exhibited slower intranuclear mobility than p72. Furthermore, the enzymatic mutants of both p72 and p82 accumulate into the stress granules. The enzymatic mutant of p82 abolishes nucleolar localization of p82. Our findings suggest the importance of IDRs and enzymatic activity of DEAD-box proteins in the intracellular distribution and formation of MLOs.
Production decline analysis of shale gas based on a probability density distribution function
Authors: Yuan Yingzhong , Qi Zhilin , Chen Zhangxing , Yan Wende , Zhao Zhiheng 
Published: February 2020

Abstract
Production decline analysis is a simple and efficient method to forecast production dynamics of shale gas. The traditional Arps decline model is also widely used in the production decline analysis of shale gas, but an obvious error is often generated. Based on the Weibull and χ2 probability density distribution function, the monotonic decreasing production prediction equations of shale gas are established. It is deduced that recently, the widely used Duong model is essentially a Weibull probability density distribution model. Decline analysis results of production data from actual shale gas well and numerical simulations indicate that the fitting results of the Weibull (Duong) model and χ2 distribution model are better than the Arps model whose deviation of early data is large. For a shale gas reservoir with very low permeability, pressure conformance area is small and it is obviously influenced by fractures. Early shale gas production rate mainly contributed to by fractures declines quickly and the later production rate mainly contributed to by the matrix declines slowly over time. The production decline curve has obvious long-tail distribution characteristics and it is a better fit to the data with a χ2 distribution model. As for the increase of permeability, the fitting accuracy of the Weibull (Duong) model gradually becomes better than the χ2 distribution model. Research results provide theoretical guidance for choosing a reasonable production decline model of a shale gas reservoir with a different permeability.