bluuebunny/crossref_metadata_2025_split huggingface dataset:
RAPID' Salmonella Chromogenic Medium
Authors: Lauer Wendy F , Martinez Frederic L , Hammack Thomas 
Published: February 2020

Abstract
RAPID' Salmonella is a chromogenic medium for isolation and detection of Salmonella spp. in food, based on two enzymatic activities. All presumptive Salmonella-positive colonies are magenta, including lactose-positive Salmonella. S. Typhi, and S. Paratyphi serotypes, due to detection of C8 esterase activity. In order to differentiate Salmonella from other Enterobacteriaceae, the medium includes a second chromogenic substrate. As part of an Emergency Response Validation due to a massive outbreak and subsequent recall, peanut butter was tested to compare the performance of RAPID' Salmonella to the U.S. Food and Drug Administration's Bacteriological Analytical Manual reference method for detection of Salmonella. Sensitivity and specificity for RAPID' Salmonella were 100.
Quantification of Paroxetine in Human Plasma by Liquid Chromatography Coupled with Electrospray Ionization Tandem Mass Spectrometry
Authors: Shah Hiten J , Kundlik Mohan L , Kakad Abhijit , Patel Nitesh K , Pandya Ankit , Khatri Vanita , Prajapati Shivkumat , Subbaiah Gunta , Patel Chhagan N 
Published: February 2020

Abstract
A rapid LC coupled with electrospray ionization (ESI) MS/MS method was developed and validated for the quantification of paroxetine in heparinized human plasma. The plasma samples were prepared by the solid-phase extraction method without drying or reconstitution. Elution was done with 0.5 mL 0.2 (v/v) formic acid in methanolacetonitrile (65 + 35, v/v). The analyte and the internal standard (IS; imipramine hydrochloride) were chromatographed on a BDS Hypersil C18 column. The analyte was analyzed by LC/MS/MS with only 1.7 min run time. An ESI interface was chosen for ionization of the analyte from the sample matrix. Selected reaction monitoring mode for detection of paroxetine and the IS were achieved by using m/z 330.17/192.10 and 281.13/86.14, respectively. The LC retention times for paroxetine and imipramine were 0.94 and 1.05 min, respectively. The method was linear in the concentration range of 0.580.0 ng/mL with r ≥0.9995. Recovery of paroxetine and imipramine ranged from 90 to 95. The assay has been successfully applied to bioequivalence study samples for estimation of paroxetine in healthy human subjects.
Evaluation of the Assurance GDS® for Salmonella Method in Foods and Environmental Surfaces: Multilaboratory Collaborative Study
Authors: Feldsine Philip T , Jucker Markus T , Kaur Mandeep , Lienau Andrew H , Kerr David E ,   Collaborators:, Adamson A , Beaupre L , Bishop J , Casasola E , Cote C , Desilets S , D’lima C , Elahimanesh P , Fitzgerald S , Forgey R , Fortin J , Gohil V , Griffin J , Hardin M , Kaur D , Ketrenos J , King A , Kupski B , Luce S , Lucia L , Maeda S , Markun D , Marquez-Gonzalez M , McClendon J , McKessock J , Nelson C , Nguyen T , O’Brien C , Ramos M , Reilly S , Roa N , Schiffelbein Z , Shaffer K , Shepherd D , Sowell S , Trujillo E , Wang S , Williams K 
Published: February 2020

Abstract
A multilaboratory collaborative study was conducted to compare the detection of Salmonella by the Assurance GDS® for Salmonella method and the Reference culture methods. Six foods, representing a variety of low microbial and high microbial load foods were analyzed. Seventeen laboratories in the United States and Canada participated in this study. No statistical differences (P &lt; 0.05) were observed between the Assurance GDS for Salmonella and the Reference culture methods for any inoculation level of any food type or naturally contaminated food, except for pasta, for which the Assurance GDS method had a higher number of confirmed test portions for Salmonella compared to the Reference method.
Determination of Ethoxyquin by High-Performance Liquid Chromatography with Fluorescence Detection and Its Application to the Survey of Residues in Food Products of Animal Origin
Authors: Aoki Yoichi , Kotani Akira , Miyazawa Naomi , Uchida Kazunari , Igarashi Yu , Hirayama Norio , Hakamata Hideki , Kusu Fumiyo 
Published: February 2020

Abstract
An analytical method using HPLC with fluorescence detection (HPLC-FL) has been developed and applied for the survey of residue levels of ethoxyquin in a variety of food products of animal origin. HPLC was performed using a silica octadecylsilane column, butylhydroxytolueneacetonitrilewater (0.05 + 800 + 200, v/v/v) mobile phase, and detection at excitation and emission wavelengths of 370 and 415 nm, respectively. HPLC/MS was used to confirm whether a chromatographic peak was ethoxyquin. The LOQ of the foods was 0.01 µg/g, except for pig fat and cow's milk, and the RSD (n = 6) at 0.1 µg/mL of the standard solution was 1.12. The accuracy of the calculated data of the standard solution was within the range of 94.0 to 101.2. Recoveries of ethoxyquin from the food products of cattle, pigs, chickens, and salmon were more than 71.0 with an RSD of &lt;9.3, except for chicken liver at different concentration levels, including the lower LOQ, the maximum residue limit (MRL), and in some tissues, twice the MRL. Residue levels of ethoxyquin in 33 commercially available food products of animal origin that were purchased on the west side of the Tokyo metropolitan area were surveyed. Contents of ethoxyquin residues in three chicken fat samples by the HPLC-FL method were 0.08, 0.03, and 0.04 µg/g, all less than the MRL (5 µg/g).
Trace-Level Detection of Atrazine Using Immuno-Chemiluminescence: Dipstick and Automated Flow Injection Analyses Formats
Authors: Chouhan Raghuraj S , Rana Kumar Vikash S , Suri C Raman , Thampi Ravindranathan K , Thakur Munna S 
Published: February 2020

Abstract
A sensitive chemiluminescence (CL)-based immunoassay technique based on both dipstick and flow injection analytical formats is reported for the detection of atrazine. In the dipstick-based immunoassay technique, antibody (anti-atrazine) was first immobilized on the nitrocellulose membranes. The dipstick was then treated with atrazine and atrazine-horseradish peroxidase conjugate (atra-HRP) to facilitate the competitive binding. The dipstick was further treated with urea-hydrogen peroxide (U-H2O2) and luminol to generate photons. The number of photons generated was inversely proportional to the atrazine concentration. In the flow injection analysis (FIA) format, the antibody was immobilized on protein-A sepharose matrix and packed in a glass capillary column, which functioned as an immunoreactor. Competitive binding of antigen and antibody occurred. The CL signals generated during the biochemical reactions were correlated with atrazine concentrations in the analytical samples. By using dipstick technique, it was possible to detect atrazine concentration down to 0.1 ng/mL; with the FIA format, the detection of atrazine was down to 0.01 ng/mL.
Immunoassays for the Rapid Detection of Gentamicin and Micronomicin in Swine Muscle
Authors: Chen Yiqiang , Li Xiangmei , He Lidong , Tang Shuheng , Xiao Xilong 
Published: February 2020

Abstract
A monoclonal antibody (mAb)-based ELISA and strip test for gentamicin (GEN) and its analogue micronomicin (MIN), are reported in this study. The conjugate gentamicin-glutaraldehyde-bovine serum albumin (GEN-GDA-BSA) was used as an immunogen. The produced anti-GEN mAB exhibited high cross-reactivity with micronomicin (MIN; 131.2) and slight or negligible cross-reactivity with other aminoglycosides. Based on this mAB, an ELISA and a strip test for GEN and MIN were developed and evaluated. The ELISA showed a 50 inhibition concentration (IC50) of 0.75 ng/mL for GEN and 0.58 ng/mL for MIN. For GEN, the average recoveries at 25200 µg/kg ranged from 73 to 91, with intraday CVs of 916 and interday CVs of 815. For MIN, the average recoveries ranged from 108 to 131, with intraday CVs of 1016 and interday CVs of 815. In contrast, the strip test for GEN or MIN had a detection limit of 5 ng/mL in phosphate-buffered saline and 50 µg/kg in muscle (n = 24), and the results could be judged within 10 min. The detection results of incurred samples analyzed by the strip test, ELISA, and HPLC indicated that the two immunoassays correlated well with the HPLC method and could be used as convenient tools for the rapid screening of GEN and MIN residues in swine muscle.
Confirmation of Hormones in Animal Serum by Liquid Chromatography/Tandem Mass Spectrometry According to European Commission Decision 2002/657
Authors: McDonald Mark , Malone Edward , McBride John 
Published: February 2020

Abstract
A novel and rapid method was developed and validated for the confirmation of endogenous and synthetic hormones in animal serum using LC/MS/MS. Detection of 17 β-estradiol and β-testosterone below the respective European Union-recommended levels of 0.1 and 0.5 µg/L was achieved, as was a required performance level of 0.1 µg/L for 17 α-estradiol and 0.5 µg/L for 17 α-testosterone, medroxyprogesterone-17-acetate, and progesterone. The method was established with dilution of serum followed by ion-exchange SPE, LC separation and MS detection with electrospray ionization, selected reaction monitoring, and positive/negative switching. Two characteristic transitions were monitored for each analyte. The method was applied to bovine, ovine, porcine, equine, and avian samples and validated according to European Commission Decision 2002/657/EC and accepted for ISO/IEC 17025:2005 accreditation. An extended calibration curve allows naturally occurring levels of endogenous hormones to be quantified. Recoveries ranged from 97.3 for 17 α-testosterone to 102.0 for 17 α-estradiol. The decision limit CCα ranged from 0.02 µg/L for 17 α- and β-estradiol to 0.12 µg/L for progesterone. Detection capability CCβ ranged from 0.03 µg/L for 17 -estradiol to 0.20 µg/L for progesterone.
A System for Repertoire Cloning and Phage Display of Murine and Leporid Antibody Fragments
Authors: Schüller Carolin , Wiebe Julia C , Pegel Antje , Kramer Karl , Skerra Arne , Hock Bertold 
Published: February 2020

Abstract
Even though rabbit antibodies (Abs) are known to exceed murine Abs with respect to specificity, affinity, and stability, cloned leporid immune repertoires have been rarely considered in recombinant Ab preparation for environmental analysis. We have developed a set of four tetp/o-based phasmid vectors that allow the efficient cloning of both murine and leporid Ab repertoires. These vectors differ in the design of the cloning sites, choice of signal peptides, and antibiotic selection markers. A set of 39 primer oligodeoxynucleotides has been developed for the PCR amplification of rabbit Ab genes, representing the most exhaustive coverage of the leporid immune repertoire described so far. The atrazine-specific murine Fab fragment K411B and a cloned V-gene repertoire from sulfonamide-immunized rabbits were used to compare these phasmids with respect to expression of Fab fragments, phagemid titers, and number of Fab displaying phagemid particles. Our results show that the ratio of recombinant phagemids could be increased up to 65% of total phage titer by utilizing the appropriate phasmid. Based on this system, the selection of two sulfonamide-specific rabbit Abs, SA2 23 and SA2 90, was accomplished after a single phagemid panning round.
Determination of Total Procyanidins in Selected Chocolate and Confectionery Products Using DMAC
Authors: Payne Mark J , Hurst William Jeffrey , Stuart David A , Ou Boxin , Fan Ellen , Ji Hongping , Kou Yan 
Published: February 2020

Abstract
A simple, specific, high-throughput colorimetric method based on the reaction of 4-dimethylaminocinnamaldehyde (DMAC) with flavan-3-ols was developed to determine total procyanidins in selected cacao-based products. Extracts of defatted samples were dispensed into a 96-well plate and reacted with DMAC. The absorbance of the reaction products was measured at 640 nm and compared to commercially available procyanidin B2 as a standard. The use of the 96-well plates and a plate reader dramatically improved sample throughput. A standard protocol was established and used for further studies. The calibration was found to be linear from 1100 ppm. The DMAC reagent reacted relatively specifically to (–)-epicatechin, (+)-catechin, epigallocatechin, gallocatechin, the gallates of catechin, epicatechin, gallocatechin, and epigallocatechin, oligomeric procyanidins of cocoa up to n = 4, and A-type procyanidins. Little or no reaction occurred with cyanidins and representative compounds of phenolic acids, flavones, flavanones, flavonols, anthocyanidins, isoflavones, and stilbenes. Sample precision studies were carried out on 10 different test materials over several weeks, and yielded RSD values of 4.0 to 9.5%. The method was ring-tested in three laboratories using blinded test materials including cocoa beans, cocoa powder, chocolate liquor, dark chocolate, and milk chocolate. There was excellent agreement of the results between laboratories.
Efficiency Evaluation of the Main Multiresidue Methods Used in Europe for the Analysis of Amitraz and Its Major Metabolites
Authors: Ferrer Carmen , Agüera Ana , Mezcua Milagros , Fernández-Alba Amadeo R , Mack Dorothea , Anastassiades Michelangelo , Gamón Miguel 
Published: February 2020

Abstract
This paper compares the performance of the three most widely employed multiresidue methods [quick, easy, cheap, effective, rugged, and safe (QuEChERS), mini-Luke, and ethyl acetate] currently used for the determination of amitraz residues in fruits. A fast and differentiated analysis of amitraz and its two main metabolites, N-2,4-dimethylphenyl-N-methylformamidine and 2,4-dimethylformanilide, was performed by HPLC-electrospray ionization-MS/MS using a triple quadrupole mass spectrometer in the positive mode. A test of the stability of the standard solutions showed a rapid hydrolysis of amitraz to the amide and amidine derivatives in solutions containing water, including QuEChERS extracts of crops that were previously acidified. Two useful mass transitions were used to confirm the presence of each analyte in the sample extracts. LOD values ranging from 0.4 to 2.0 g/kg were obtained. Linearity of response over 2 orders of magnitude was demonstrated (r2 &gt; 0.999) in solvent and pear extract. The recovery studies were performed on pear blanks spiked at two concentration levels, 50 and 500 g/kg (N 5). Best recoveries, ranging from 75 to 103, were obtained by the application of the QuEChERS method with CV &lt;8 in all cases. The QuEChERS method was applied to a monitoring study carried out by the Chemical and Veterinary Investigation Office Stuttgart laboratory. From the 63 pear samples analyzed, 21 contained amitraz residues (expressed as sum) ranging from 0.02 to 2.9 mg/kg. Amitraz parent was detected only in a few cases at very low concentration levels, with N-2,4-dimethylphenyl-N-methylformamidine being the metabolite almost entirely representing the total residue. These results emphasize that the residue situation is clearly underestimated if only the parent compound is targeted, and they reinforce how important it is to include amitraz in the target scope of pesticide residue laboratories, especially since the concentrations detected exceeded the Acute Reference Dose in the majority of cases and pose a health risk to the consumer.
Determination of Tadalafil in Pure Powder and Tablet Dosage Form by High-Performance Liquid Chromatography
Authors: Barot Tushar G , Patel Popatbhai K 
Published: February 2020

Abstract
A simple and accurate method to determine tadalafil (TAD) in pure powder and tablet dosage form was developed and validated using HPLC. The separation was achieved on an Xterra RP18 column (150 4.6 mm id, 3.5 m) in the isocratic mode using bufferacetonitrile (70 + 30, v/v), adjusted to pH 7.00 0.05 with triethylamine as the mobile phase at a flow rate of 1.0 mL/min. The photodiode array detector was set at 225 nm. Quantification was achieved over the concentration range of 50.7152.10 g/mL with mean recovery of 100.26 0.75. The method was validated and found to be simple, accurate, precise, and specific. The method was successfully applied for the determination of TAD in pure powder and tablet dosage form without interference from common excipients or degradation products.
Validation of a Stability-Indicating RP-HPLC Method for the Determination of Entecavir in Tablet Dosage Form
Authors: Dalmora Sérgio Luiz , Sangoi Maximiliano da Silva , Nogueira Daniele Rubert , Silva Lucélia Magalhães da 
Published: February 2020

Abstract
An RP-HPLC method was validated for the determination of entecavir in tablet dosage form. The HPLC method was carried out on a Gemini C18 column (150 4.6 mm id) maintained at 30C. The mobile phase consisted of acetonitrilewater (95 + 5, v/v)/potassium phosphate buffer (0.01 M, pH 4; 9 + 91, v/v) pumped at a flow rate of 1.0 mL/min. Photodiode array detection was at 253 nm. The chromatographic separation was obtained with a retention time of 4.18 min, and the method was linear in the range of 0.5200 g/mL (r2 0.9998). The specificity and stability-indicating capability of the method was proven through forced degradation studies, which also showed that there was no interference of the excipients and an increase of the cytotoxicity only by the basic condition. The accuracy was 101.19, with bias lower than 1.81. The LOD and LOQ were 0.39 and 0.5 g/mL, respectively. Method validation demonstrated acceptable results for precision and robustness. The proposed method was applied for the analysis of tablet formulations, to improve QC and assure therapeutic efficacy.
TEMPO® EC for the Enumeration of Escherichia coli in Foods: Collaborative Study
Authors: Crowley Erin , Bird Patrick , Torontali Marianne , Goetz Katherine , Agin James , Goins David , Johnson Ronald ,   Collaborators:, Achen M , Barlowe A , Clark M , Colón-Reveles J , Dixon K , Fisher K , Hanson P , Jechorek R , Johnson L , Kelly M , Kim S , Kohler H , Kondratko D , Kupski B , McCallum K , Mills J , Mohnke F , Moon B , Olson B , Reed C , Sauter J , Thompson L 
Published: February 2020

Abstract
The automated method for enumeration of Escherichia coli, TEMPO&lt;sup/&gt; EC, in foods uses a dehydrated culture medium and enumeration card containing 48 wells across three different dilutions for the automatic determination of the most probable number (MPN). The alternative method was compared in a multilaboratory collaborative study to AOAC Official MethodSM 966.24. Six food types were artificially contaminated with E. coli: raw ground beef, bagged lettuce, cooked chicken, pasteurized crabmeat, frozen green beans, and pasteurized whole milk. All foods were analyzed for E. coli counts by 11 collaborating laboratories throughout the United States. Test portions from the six food types each contaminated at four different contamination levels were evaluated. The study demonstrated that the TEMPO EC method is a reliable, automated assay for the enumeration of E. coli in foods.
Finding and Confirming Nontargeted Pesticides Using GC/MS, LC/Quadrupole-Time-of-Flight MS, and Databases
Authors: Meng Chin-Kai , Zweigenbaum Jerry , Fürst Peter , Blanke Eva 
Published: February 2020

Abstract
Two methods are described for identifying unknowns in complex matrixes. One approach, suitable for nonpolar and thermally stable compounds, uses GC/MS with a deconvolution technique, followed by a spectral library search. The second approach, suitable for polar and thermally labile compounds, uses LC/quadrupole-time-of-flight (LC/Q-TOF) MS with a Molecular Feature Extractor (MFE), followed by a database search on the exact mass of each found compound. Two example analyses are presented to illustrate the GC/MS method. The first example processes data files obtained by a multiresidue analysis of pesticides in surface water. In this example, 71 pesticides were identified using Deconvolution Reporting Software in conjunction with Automated Mass Spectral Deconvolution and Identification System software. The second example illustrates the deconvolution approach in detail using peaches and pears analyzed after extraction by the quick, easy, cheap, effective, rugged, and safe (QuEChERS) protocol. The LC/Q-TOF approach is illustrated through analysis of a grape extract prepared by the QuEChERS protocol. The resulting total ion chromatogram was found by the MFE to contain 510 chemicals (components). The masses of found chemicals were subsequently searched against an Exact Mass Database of hundreds pesticides, and 15 exact mass hits were found. Several of these exact mass hits were selected for further confirmation by MS/MS analysis using the same LC/Q-TOF.
Determination of Hydrogen Cyanide in Cigarette Mainstream Smoke by LC/MS/MS
Authors: Mottier Nicolas , Jeanneret Florent , Rotach Michel 
Published: February 2020

Abstract
An LC/MS/MS method is presented for the determination of hydrogen cyanide in cigarette mainstream smoke. Cyanide is derivatized with 2,3-naphthalenedicarboxaldehyde and taurine to form a benzo[f]isoindole derivative, which is then analyzed by LC/MS/MS. Isotopic KCN (K13C15N) was used as an internal standard. The regression equation was linear within the range 2.4331 ng/mL for cyanide with a correlation coefficient &gt;0.999. The LOD was calculated as 4.1 ng/cigarette. The influence of the sodium hydroxide trapping solution concentration on the results is discussed. A 1 M solution showed the best results in terms of sample stability and trapping efficiency. The method proved to be robust, reliable, and more selective than current methods, making it a logical choice for determination of total cyanide in cigarette smoke.
Validated HPTLC Method for Simultaneous Quantitation of Paracetamol, Diclofenac Potassium, and Famotidine in Tablet Formulation
Authors: Khatal Laxman D , Kamble Asmita Y , Mahadik Mahadeo V , Dhaneshwar Sunil R 
Published: February 2020

Abstract
A sensitive, simple, selective, precise, and accurate HPTLC method of analysis for paracetamol, diclofenac potassium, and famotidine both as a bulk drug and in tablet formulation was developed and validated. The method used HPTLC aluminum plates precoated with silica gel 60F254 as the stationary phase, and the mobile phase consisted of tolueneacetonemethanolformic acid (5 + 2 + 2 + 0.01, v/v/v/v). Densitometric evaluation of the separated zones was performed at 274 nm. This system was found to give compact spots for paracetamol (Rf value = 0.62 0.03), diclofenac potassium (0.75 0.02), and famotidine (0.17 0.03). The linear regression analysis data for the calibration plots showed a good linear relationship over the concentration range of 16259750 ng/spot for paracetamol, 2501500 ng/spot for diclofenac potassium, and 100600 ng/spot for famotidine. The method was validated for precision, robustness, and recovery according to International Conference on Harmonization guidelines. No chromatographic interference from the tablet excipients was found. Statistical analysis showed that the method was repeatable and selective for the simultaneous quantitation of the three drugs in tablet formulation and for routine quality control of raw materials of the drugs.