bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Chloramphenicol Residues in Bee Pollen by Liquid Chromatography/TandemMass Spectrometry
Authors: Fujita Kazuhiro , Ito Hironobu , Nakamura Munetomo , Watai Masatoshi , Taniguchi Makoto 
Published: February 2020

Abstract
A novel liquid chromatographic/tandem mass spectrometric (LC/MS/MS) method was developed for the trace residue determination of chloramphenicol (CAP) in bee pollen. CAP was extracted from bee pollen with a mixture of methanol and 1 metaphosphoric acid solution, followed by a 2-stage solid-phase extraction enrichment and cleanup. The first stage involved a polymeric cartridge, and the second stage involved an alumina neutral cartridge. The LC separation was performed on a C18 column with 10 mM ammonium formateacetonitrile (7 + 3) as the mobile phase and MS detection with negative-ion electrospray ionization. CAP-d5 was used as the internal standard. The method was validated according to Commission Decision 2002/657/EC. The calibration curves were linear between 0.1 and 5.0 ng/mL, and overall recoveries ranged from 98 to 113. Decision limits (CC) ranged from 0.05 to 0.07 g/kg, and detection capabilities (CC) ranged from 0.08 to 0.12 g/kg. The developed method was applied to 11 samples.
Thin-Layer Chromatography-Densitometric Analysis of -Mangostin Content in Garcinia mangostana Fruit Rind Extracts
Authors: Pothitirat Werayut , Gritsanapan Wandee 
Published: February 2020

Abstract
The fruit rinds of mangosteen (Garcinia mangostana Linn.) have long been used as traditional medicines for treatment of skin infections, wounds, and diarrhea. A simple thin-layer chromatography (TLC)-densitometric method has been developed for the simultaneous quantification of -mangostin in the extracts from unripe and ripe fruit rinds of G. mangostana. It was found in the ranges of 10.48 0.83 and 16.65 0.38 (w/w) in the dried unripe and ripe fruit rinds, respectively. The method was validated for linearity, precision, accuracy, limit of detection (LOD), and limit of quantitation (LOQ). The linearity was found over the range of 100500 ng/spot with regression coefficient 0.999. Intraday and interday precision studies showed the relative standard deviation was &lt;2. Accuracy of the method was determined by a recovery study conducted at 3 different levels, and the average recovery was 99.49. The LOD and LOQ were 40 and 100 ng, respectively. The proposed TLC-densitometric method was found to be simple, precise, specific, sensitive, and accurate. This method can be used for routine quality control of raw material of G. mangostana fruit rind, extract, and its products. It also can be applied in quantifying this marker compound in other drugs.
Thin-Layer Chromatography-Densitometric Measurements for Determination of N-(Hydroxymethyl)nicotinamide in Tablets and Stability Evaluation in Solutions
Authors: Hubicka Urszula , Krzek Jan , uka Justyna 
Published: February 2020

Abstract
A thin-layer chromatography (TLC)-densitometric method was developed to determine N-(hydroxymethyl)nicotinamide in tablets and basic solutions along with nicotinic acid. Analysis was performed on silica gel F254 plates using chloroformethanol (2 + 3, v/v) mobile phase. The densitometric observations were made at 260 nm. The results showed good precision and accuracy; relative standard deviation was 2.37, and recovery ranged from 97.60 to 100.82. The limit of detection was 0.1 g/spot, while the linearity range was from 0.2 to 1.75 g/spot. Applicability of the newly developed method was tested for determination of N-(hydroxymethyl)nicotinamide in the preparation Cholamid&lt;sup/&gt;. Densitometric measurements were used to evaluate stability of N-(hydroxymethyl)nicotinamide in basic solutions. It was found that decomposition corresponded to first-order reaction kinetics. The computed kinetic and thermodynamic parameters at 30C were as follows: k 0.00675/min, t0,5 1.71 h, t0,1 0.26 h, and Ea 44.75 kJ/mol.
Method for the Determination of Lycopene in Supplements and Raw Material by Reversed-Phase Liquid Chromatography: Single-Laboratory Validation
Authors: Müller André , Pietsch Bernd , Faccin Nicole , Schierle Joseph , Waysek Edward H 
Published: February 2020

Abstract
A single-laboratory validation study was conducted for a liquid chromatographic (LC) method for the determination of total and all-trans-lycopene in a variety of dietary supplements and raw materials. Gelatin-based and other water-dispersible beadlets, or tablets, capsules, and softgels containing such product forms, were digested with protease. Alginate formulations and the respective applications were treated with an alkaline sodium EDTA acetate buffer to release lycopene from the matrix. Lycopene and other carotenoids were extracted from the resulting aqueous suspensions with dichloromethane and ethanol. Oily product forms were directly dissolved in dichloromethane and ethanol. The extracts were chromatographed on an isocratic high-performance LC system using a C16 alkylamide modified silica column that provided satisfactory resolution of all-trans-lycopene from its predominant cis-isomers and separated the lycopene isomers from other carotenoids such as - and -carotene, cryptoxanthin, lutein, and zeaxanthin. The within-day precision relative standard deviation (RSD) for the determination of total lycopene ranged from 0.9 to 5.7 over concentration ranges of 50200 g/kg for raw materials and 0.324 g/kg for dietary supplements. The intermediate precision RSD (total RSD) ranged from 0.8 to 8.9. Recoveries obtained for beadlet and tablet material for the different extraction variants ranged from 95.0 to 102.1 at levels of 0.0220 g/kg for tablets and from 95.0 to 101.1 at levels of 1200 g/kg for beadlet material.
Standard Reference Materials for Analysis of Dietary Supplements
Authors: Sharpless Katherine E , Duewer David L 
Published: February 2020

Abstract
National Institute of Standards and Technology (NIST), in collaboration with the National Institutes of HealthOffice of Dietary Supplements and the U.S. Food and Drug Administration, is producing Standard Reference Materials (SRMs) for dietary supplements. These and other natural-matrix SRMs should be used in method validation, characterization of in-house quality control materials, and to establish traceability.
Development of a Stability-Indicating High-Performance Liquid Chromatographic Method for the Simultaneous Determination of Alprazolam and Sertraline in Combined Dosage Forms
Authors: Pathak Ashutosh , Rajput Sadhana J 
Published: February 2020

Abstract
The objective of the current study was to develop a validated stability-indicating high-performance liquid chromatographic method for alprazolam and sertraline in combined dosage forms. The method was validated by subjecting the drugs to forced decomposition under hydrolysis, oxidation, photolysis, and thermal stress conditions prescribed by the International Conference on Harmonization. The drugs were successfully separated from major and minor degradation products on a reversed-phase C18 column by using 75 mM potassium dihydrogen phosphate buffer (pH 4.3)acetonitrilemethanol (50 45 5, v/v/v) as the mobile phase with determination at 227 nm. The flow rate was 0.9 mL/min. The method was validated with respect to linearity, precision, accuracy, system suitability, and robustness. The responses were linear over the ranges of 180 and 5200 g/mL for alprazolam and sertraline, respectively. The recoveries of both drugs from a mixture of degradation products were in the range of 97101. The utility of the procedure was verified by its application to marketed formulations that were subjected to accelerated stability studies. The method distinctly separated the drugs and degradation products, even in actual samples. The products formed in marketed tablets were similar to those formed during stress studies.
Estimation of Dietary Intake of Biotin and Its Measurement Uncertainty Using Total Diet Samples in Osaka, Japan
Authors: Murakami Taro , Yamano Tetsuo , Nakama Akihiko , Mori Yoshiaki 
Published: February 2020

Abstract
Single-laboratory method performance parameters were evaluated for analysis of biotin in total diet samples by hydrolyzed extraction and microbiological assay with Lactobacillus plantarum. The method was shown to be accurate, repeatable, rugged, and applicable for the determination of biotin in a broad range of matrixes and concentrations of total diet samples. The measurement uncertainty was evaluated with all food sample groups by combining the relative uncertainty of precision, recovery from each food group, and interday variation factors calculated from the ruggedness test results. The estimated daily intake of biotin in Osaka city and its expanded measurement uncertainty were 70.1 11.2 g/day. The value was 1.6 times higher than the current adequate intake of biotin in Japan.
Single-Laboratory Validation and Uncertainty Analysis of 82 Pesticides Determined in Pomegranate, Apple, and Orange by Ethyl Acetate Extraction and Liquid Chromatography/Tandem Mass Spectrometry
Authors: Banerjee Kaushik , Oulkar Dasharath P , Patil Shubhangi B , Patil Sangram H , Dasgupta Soma , Savant Rahul , Adsule Pandurang G 
Published: February 2020

Abstract
Single-laboratory validation results are reported for the multiresidue determination of 82 pesticides at 10 ng/g levels in pomegranate, apple, and orange. Samples were extracted with ethyl acetate, and the extracts were cleaned up by dispersive solid-phase extraction with primary secondary amine sorbent. The concentrations of the pesticides were estimated within 18 min of chromatographic run time by liquid chromatography/mass spectrometry with multiple-reaction monitoring. The method was reproducible (HorRat of &lt;0.5 at 10 ng/g) with measurement uncertainties of &lt;15 for all the compounds at 10 ng/g in all 3 matrixes. The limits of quantitation ranged from 2.5 to 5.0 ng/g with recoveries of 70120 for most pesticides. Matrix-induced signal suppressions were significantly higher in orange compared with those in pomegranate and apple. The method offers a less expensive and safer alternative to the existing multiresidue analysis methods for fruits and vegetables.
Detection of Parvalbumin, a Common Fish Allergen Gene in Food, by Real-Time Polymerase Chain Reaction
Authors: Sun Min , Liang Chengzhu , Gao Hongwei , Lin Chao , Deng Mingjun 
Published: February 2020

Abstract
Fish, as one of the most common causes of IgE-mediated food hypersensitivity, has recently received increasing attention from the food industry and legislative and regulatory agencies. A real-time polymerase chain reaction assay based on TaqMan-MGB probe technology was developed for the detection of parvalbumin, a major fish allergen gene. The assay had a sensitivity up to 5 pg purified fish DNA and had no cross-reaction with other species, such as cattle, sheep, swine, chicken, shrimp, lobster, crab, squid, clam, rice, soybean, maize, and potato. The coefficient of variation for both intra- and interexperimental variability demonstrated high reproducibility and accuracy. The assay proved to be a potential tool for the detection and label management of fish allergens in food.
Proficiency Test for Chemical Laboratories for the Analysis of a Pesticide in a Formulated Product: Interlaboratory Study
Authors: Sanyal Doyeli , Rani Anita 
Published: February 2020

Abstract
A multilaboratory proficiency testing program was conducted by the National Accreditation Board for Testing and Calibration Laboratories (India) and coordinated by the Institute of Pesticide Formulation Technology. This program was conducted to compare the performance of individual laboratories in the area of pesticide formulation (Chlorpyrifos 20 EC) analysis. A total of 24 laboratories in India participated. Analysis of 2 parameters (i.e., estimation of the active ingredient and the acidity) of 2 samples of Chlorpyrifos 20 EC was the objective of this program. Homogeneity tests were performed before sample distribution. Performance of the participating laboratories was evaluated by using new robust statistics given in the guidelines of the National Association of Testing Authorities, Australia. Results were collated and statistically computed to calculate the value of 2 types of Z-scores (Zwi and Zbi). In addition to the statistical analysis, a graphical representation such as the Youden plot was also generated to evaluate the performance of participating laboratories.
Determination of Starch, Including Maltooligosaccharides, in Animal Feeds: Comparison of Methods and a Method Recommended for AOAC Collaborative Study
Authors: Hall Mary B 
Published: February 2020

Abstract
Starch is a nutritionally important carbohydrate in feeds that is increasingly measured and used for formulation of animal diets. Discontinued production of the enzyme Rhozyme-S required for AOAC Method 920.40 invalidated this method for starch in animal feeds. The objective of this study was to compare methods for the determination of starch as potential candidates as a replacement method and for an AOAC collaborative study. Many starch methods are available, but they vary in accuracy, replicability, and ease of use. After assays were evaluated that differed in gelatinization method, number of reagents, and sample handling, and after assays with known methodological defects were excluded, 3 enzymaticcolorimetric assays were selected for comparison. The assays all used 2-stage, heat-stable, -amylase and amyloglucosidase hydrolyses, but they differed in the gelatinization solution (heating in water, 3-(N-morpholino) propanesulfonic acid buffer, or acetate buffer). The measured values included both starch and maltooligosaccharides. The acetate buffer-only method was performed in sealable vessels with dilution by weight; it gave greater starch values (26 percentage units of sample dry matter) in the analysis of feed/food substrates than did the other methods. This method is a viable candidate for a collaborative study.
Validation of a Modification to Performance-Tested MethodSM 070601: Reveal® Listeria Test for Detection of Listeria spp. in Selected Foods and Selected Environmental Samples
Authors: Alles Susan , Peng Linda X , Mozola Mark A 
Published: February 2020

Abstract
A modification to Performance-Tested MethodSM (PTM) 070601, Reveal® Listeria Test (Reveal), is described. The modified method uses a new media formulation, LESS enrichment broth, in single-step enrichment protocols for both foods and environmental sponge and swab samples. Food samples are enriched for 2730 h at 30C and environmental samples for 2448 h at 30C. Implementation of these abbreviated enrichment procedures allows test results to be obtained on a next-day basis. In testing of 14 food types in internal comparative studies with inoculated samples, there was a statistically significant difference in performance between the Reveal and reference culture U.S. Food and Drug Administration's Bacteriological Analytical Manual (FDA/BAM) or U.S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) methods for only a single food in one trial (pasteurized crab meat) at the 27 h enrichment time point, with more positive results obtained with the FDA/BAM reference method. No foods showed statistically significant differences in method performance at the 30 h time point. Independent laboratory testing of 3 foods again produced a statistically significant difference in results for crab meat at the 27 h time point; otherwise results of the Reveal and reference methods were statistically equivalent. Overall, considering both internal and independent laboratory trials, sensitivity of the Reveal method relative to the reference culture procedures in testing of foods was 85.9 at 27 h and 97.1 at 30 h. Results from 5 environmental surfaces inoculated with various strains of Listeria spp. showed that the Reveal method was more productive than the reference USDA-FSIS culture procedure for 3 surfaces (stainless steel, plastic, and cast iron), whereas results were statistically equivalent to the reference method for the other 2 surfaces (ceramic tile and sealed concrete). An independent laboratory trial with ceramic tile inoculated with L. monocytogenes confirmed the effectiveness of the Reveal method at the 24 h time point. Overall, sensitivity of the Reveal method at 24 h relative to that of the USDA-FSIS method was 153. The Reveal method exhibited extremely high specificity, with only a single false-positive result in all trials combined for overall specificity of 99.5.
Novel Method for Identification and Quantification of Methanol and Ethanol in Alcoholic Beverages by Gas Chromatography-Fourier Transform Infrared Spectroscopy and Horizontal Attenuated Total ReflectanceFourier Transform Infrared Spectroscopy
Authors: Sharma Kakali , Sharma Shiba Prasad , Lahiri SujitChandra 
Published: February 2020

Abstract
Numerous methods are being used to identify and quantify methanol and ethanol in alcoholic beverages, including country liquors. Some of the known methods are density and refractive index measurements, and spectrophotometric measurements using Schiff's reagent or chromatropic acid. Other advanced techniques involve head space gas chromatography (GC), GCflame ionization detection, high-performance liquid chromatography, enzymatic reactions, and biosensors. However, identification and quantification of methanol and ethanol in beverages can be accurately done using GC-Fourier transform infrared spectroscopy (FTIR) and horizontal attenuated total reflectance (HATR)-FTIR. Identification of alcohols is possible from library matching of the IR spectra obtained from GC-FTIR. In water, methanol and ethanol show a very strong peak for CO, stretching at 1015.3 and 1044.2 cm1, respectively. The strong absorption of vibrational stretching frequency of CO present in alcohols was used for quantification purposes. The absorptions of CO group frequency of alcohols in water mixtures were measured using HATR-FTIR with a zincselenide crystal. Samples were placed directly on the HATR crystal, with alcohol concentrations ranging from 0.2 to 50.0 (v/v). The plot of absorptions against concentrations of methanol and ethanol obeyed Beer's law (r2 0.9998 and 0.9987, respectively), from which alcohol in the mixtures was quantified. Propan-2-ol and n-butanol showed no interference. The method is validated from absorption measurements of known mixtures of standard ethanol in water. This is a simple, specific, rapid, accurate, and nondestructive method of identification and quantification of methanol and ethanol in mixtures. It can be used to ascertain methanol contamination in alcoholic beverages that can lead to death or methanol poisoning by alcohol consumption.
Column Liquid Chromatography/Electrospray Ionization-Time of Flight-Mass Spectrometry and Ultraperformance Column Liquid Chromatography/Mass Spectrometry Methods for the Determination of Ginkgolides and Bilobalide in the Leaves of Ginkgo biloba and Dietary Supplements
Authors: Avula Bharathi , Wang Yan-Hong , Smillie Troy J , Khan Ikhlas A 
Published: February 2020

Abstract
Column liquid chromatography/electrospray ionization-time of flight-mass spectrometry (LC/ESI-TOF-MS) and ultraperformance column liquid chromatographic/MS (UPLC/MS) methods were developed for the determination of 5 terpenelactones in the leaves of Ginkgo biloba. The separation was performed using a C18 column and a mobile phase composed of water and acetonitrile. The limit of detection (LOD) values for ginkgolide J, ginkgolide C, ginkgolide B, and ginkgolide A were found to be in the range of 110 ng/mL by both methods, and the bilobalide LOD was 200 ng/mL by LC/ESI-TOF and 35 ng/mL by UPLC/MS. Using the optimized method, 4 commercial products were analyzed. Concentrations of total marker compounds in these products were in the 0.0915.4 range, with individual ginkgo terpenelactones being detected at ppb levels. LC/MS with ESI is described for the identification and quantification of ginkgolides and bilobalide in plant samples and dietary supplements that claim to contain G. biloba. These methods involve the use of the M NH4&lt;sup/&gt; and M H&lt;sup/&gt; ions of sesquiterpenoids in the positive ion mode with extractive ion monitoring by LC/ESI-TOF-MS and selected ion monitoring by UPLC/MS. The LC method coupled with MS analysis yielded well-separated peaks which resulted in a clear identification of the compounds.
Development of a Rapid Resolution Liquid Chromatographic Method for Simultaneous Analysis of Four Alkaloids in Rhizoma coptidis Under Different Cultivation Conditions
Authors: Qiao Yan-Ling , Sheng Yu-Xin , Wang Li-Qun , Zhang Jin-Lan 
Published: February 2020

Abstract
A sensitive and specific method using rapid resolution liquid chromatography coupled with UV-Vis detection was developed for fingerprint analysis of Rhizoma coptidis and simultaneous determination of 4 alkaloids: jatrorrhizine, coptisine, palmatine, and berberine. Samples of R. coptidis grown under different cultivation conditions and from different habitats were analyzed. The analysis was performed using a reversed-phase octylsilyl (C8) column and gradient elution. The mobile phase consisted of acetonitrile and 20 mmol/L KH2PO4. Each analysis was completed within 3.5 min. The method showed good linearity within test ranges of 4.7547.50 g/mL for jatrorrhizine, 20.60164.80 g/mL for coptisine, 18.07180.73 g/mL for palmatine, and 89.70717.57 g/mL for berberine. The method showed good precision, repeatability, and stability for quantification of the 4 alkaloids. The lower limit of detection was 0.19 ng for jatrorrhizine, 0.21 ng for coptisine, 0.15 ng for palmatine, and 0.14 ng for berberine. The lower limit of quantification was 0.57 ng for jatrorrhizine, 0.82 ng for coptisine, 0.55 ng for palmatine, and 0.27 ng for berberine. The overall recovery ranged from 96.30 to 104.10 for the 4 alkaloids. The method is accurate, rapid, and convenient, and it is suitable for routine quality control of R. coptidis.
New Approaches for Determination of Glyphosate and Aminomethylphosphonic Acid from Different Tea SamplesProspects and Limits of Cleanup with Molecularly Imprinted Polymer and Titanium Dioxide
Authors: Kittlaus Stefan , Lipinski Jrgen , Speer Karl 
Published: February 2020

Abstract
Glyphosate is the most commonly used herbicide worldwide. To identify glyphosate and its metabolite, aminomethylphosphonic acid (AMPA), in the difficult-to-analyze matrix of tea, new methods were developed. The main emphasis was placed on the cleanup procedure. Two different solid-phase extraction methods were tested and evaluated: one with molecularly imprinted polymers, and the other with immobilized titanium dioxide. The optimization was carried out on the basis of aqueous standard solutions and spiked tea extracts. Validated results were presented for pipet tips that contained immobilized titanium dioxide. After the extraction of glyphosate from tea samples using hydrochloric acid (0.1), glyphosate and AMPA were concentrated on the adsorbent by pipetting up and down several times without changing the tip. The elution was carried out subsequent to a washing step with 5 ammonia. The extract was derivatized with 2,2,2-trifluoroacetic acid and 2,2,2-trifluoroethanol and then analyzed by GC with MS detection in the negative chemical ionization mode. Quantification was carried out in the selected-ion monitoring mode based on the m/z ratio of characteristic ions due to the ionization process. For glyphosate m/z = 370 was applied, and m/z = 351 for AMPA. The detection limit was 0.03 mg/kg tea for glyphosate and 0.006 mg/kg tea for AMPA. The recoveries for the tested working range (0.1 to 2.8 mg/kg tea) were low but constant at 14 and 12, respectively. Altogether, the method presented here can be carried out easily and quickly, and it gives reliable information on the presence of the analytes in a sample. Quantification is also possible using standard addition.