bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Fully Automated System for Analysis of Pesticides in Water: On-Line Extraction Followed by Liquid Chromatography- Tandem Photodiode Array/Postcolumn Derivatization/ Fluorescence Detection
Authors: Patsias John , Papadopoulou-Mourkidou Euphemia 
Published: February 2020

Abstract
A fully automated system for on-line solid phase extraction (SPE) followed by high-performance liquid chromatography (HPLC) with tandem detection with a photodiode array detector and a fluorescence detector (after postcolumn derivatization) was developed for analysis of many chemical classes of pesticides and their major conversion products in aquatic systems. An automated on-line-SPE system (Prospekt) operated with reversed-phase cartridges (PRP-1) extracts analytes from 100 mL acidified (pH = 3) filtered water sample. On-line HPLC analysis is performed with a 15 cm C18 analytical column eluted with a mobile phase of phosphate (pH = 3)-acetonitrile in 25 min linear gradient mode. Solutes are detected by tandem diode array/ derivatization/fluorescence detection. The system is controlled and monitored by a single computer operated with Millenium software. Recoveries of most analytes in samples fortified at 1 μg/L are &gt;90%, with relative standard deviation values of &lt;5%. For a few very polar analytes, mostly Λ/-methylcarbamoyloximes (i.e., aldicarb sulfone, methomyl, and oxamyl), recoveries are &lt;20%. However, for these compounds, as well as for the rest of the N-methylcarbamates except for aldicarb sulfoxide and butoxycarboxim, the limits of detection (LODs) are 0.005-0.05 μg/L. LODs for aldicarb sulfoxide and butoxycarboxim are 0.2 and 0.1 μg, respectively. LODs for the rest of the analytes except 4-nitrophenol, bentazone, captan, decamethrin, and MCPA are 0.05-0.1 μg/L. LODs for the latter compounds are 0.2-1.0 μg/L. The system can be operated unattended.
Use Patterns and Residual Levels of Organophosphate Pesticides on Vegetables in Trinidad, West Indies
Authors: Yen Ivan Chang , Bekele Isaac , Kalloo Carlyle 
Published: February 2020

Abstract
The twin-island state of Trinidad and Tobago produces much of the fresh fruit and vegetables consumed locally, although some are exported to Europe and North America. On average, approximately 1500 tons of pesticides are imported annually, of which about 10-15% are organophosphates. A survey of local farmers revealed that a wide range of pesticides are used and that the same pesticides are used on several crops to control different pests. Application rates exceeding manufacturers' recommendations are also common, as is the disregard of recommended preharvest intervals after pesticide application. Praedial larceny and subsequent sale of freshly sprayed crops also contribute to the risks posed to consumers by pesticide residues. A market basket survey of produce conducted between October 1996 and May 1997 in Trinidad for organophosphate pesticides showed that 10% of produce exceeded the internationally acceptable maximum residue limits (MRLs) for the respective pesticides. Celery constituted 6.5% of all such samples, with over 83% of celery samples exceeding the MRL. Organophosphate pesticides detected were methamidophos, triazophos, prophenofos, diazinon, ethion, pirimiphos methyl, malathion, and dimethoate, with the first 4 being the most commonly detected. There is an urgent need for comprehensive monitoring and control of pesticides on produce by local regulatory agencies, especially because the above data relate only to one class of pesticides. The education of farmers on safe operating practices regarding pesticide application and observation of recommended preharvest intervals for applied pesticides is also required.
Authentication of Straight Whiskey by Determination of the Ratio of Furfural to 5-Hydroxymethyl-2-Furaldehyde
Authors: Jaganathan James , Dugar Sumer M 
Published: February 2020

Abstract
Bureau of Alcohol, Tobacco and Firearms regulations require that a straight whiskey be aged in a freshly charred oak barrel for a minimum of 2 years and that it not be colored with added caramel. The regulations, however, permit addition of caramel in blended whiskeys. Blended whiskeys are usually produced by mixing a straight whiskey with neutral spirits which causes loss of color intensity. Caramel addition is permitted to compensate for this loss. Thus, it is not possible to authenticate the standard of identity of a straight whiskey by measurement of color intensity. Our investigations suggest that furfural (2-furaldehyde) and 5-hydroxymethyl-2-furaldehyde are imparted into a straight whiskey during aging in a freshly charred oak barrel. Caramel, on the other hand, imparts only 5-hydroxymethyl-2-furaldehyde. Thus, the measurement of the concentrations of furfural and 5-hydroxymethyl-2-furaldehyde and their ratio could effectively authenticate the standard of identity of straight whiskeys. This study shows that straight whiskeys aged in freshly charred oak barrels for a period of 2 years or more have a 2:1 or higher ratio of furfural to 5-hydroxymethyl-2-furaldehyde. A high-performance liquid chromatographic method for the determination of furfural and 5-hyroxy- methyl-2-furaldehyde at low parts-per-million levels is described.
Chromatographic Methods for Analysis of Aminoglycoside Antibiotics
Authors: Isoherranen Nina , Soback Stefan 
Published: February 2020

Abstract
Aminoglycosides are antimicrobial agents used frequently in treatment of human and animal diseases caused by aerobic, gram-negative bacteria. Because of the toxicity of these compounds, considerable effort has been attributed to analysis of aminoglycoside content in drug preparations, in serum and urine specimen in therapeutic drug monitoring, and in edible animal tissues in residue control. The present review emphasizes the analytical problems associated with aminoglycoside analysis. Screening methods based on microbiological and immunological procedures were briefly discussed. Gas chromatography and especially high-performance liquid chromatography appeared the most widely used chemical methods for the analysis of these compounds. Due to lack of volatility, chromophore, and hydrophility of aminoglycosides, most methods applied derivatization for enhancement of their chromatographic characteristics. The applicability and advantages of the various derivatization procedures were discussed in detail. A wide variety of detection methods, including mass spectrometry have been used. Packed column separation was generally used for gas chromatographic separation. In liquid chromatography, reversed phase, ion pair, ion exchange, and normal phase separation has been employed. Mass spectrometry, as a detection method, was discussed in detail. Extraction procedures from body fluids and tissues were emphasized. The performance and the operational conditions of the methods were described and detailed information of the data was provided also in table format.
Multiresidue Chromatographic Method for the Determination of Macrolide Residues in Muscle by High-Performance Liquid Chromatography with UV Detection
Authors: Juhel-Gaugain Murielle , Anger Béatrice , Laurentie Michel 
Published: February 2020

Abstract
A high-performance liquid chromatographic (HPLC) method for the simultaneous determination of tilmicosin, tylosin, spiramycin, and its major metabolite neospiramycin was developed that is suitable for porcine, bovine, and poultry muscles. Macrolide residues were extracted from muscle with acetonitrile, fat was removed by liquid-liquid extraction with isooctane, and the extract was then cleaned on Bond Elut C18 cartridges. The HPLC separation was performed on an Inertsil ODS3 C18 column (150 × 4 mm) with 0.05% trifluoroacetic acid-acetonitrile in a gradient mode. Two different chromatographic gradients were used for tilmicosin-tylosin and spiramycin-neospiramycin, and the detection wavelengths were 287 and 232 nm, respectively. The method was validated from ½ the maximum residue limit (MRL) to 4 times the MRL with pork muscle samples. Mean recoveries were 60, 63.5, 51, and 42% for tilmicosin, tylosin, spiramycin, and neospiramycin, respectively. The detection limits are 15 μg/kg for tilmicosin and tylosin, 30 μg/kg for spiramycin, and 25 μg/kg for neospiramycin. Linearity, precision, and accuracy of the method were also tested.
Liquid Chromatographic Determination of para-Toluenesulfonamide in Edible Fillet Tissues from Three Species of Fish
Authors: Meinertz Jeffery R , Schmidt Larry J , Stehly Guy R , Gingerich William H 
Published: February 2020

Abstract
Chloramine-T (N-sodium-N-chloro-p-toluene-sulfonamide) is a candidate therapeutic drug for treating bacterial gill disease, a predominant disease of a variety of fish species. Research has been initiated to obtain the U.S. Food and Drug Administration’s (FDA) approval for the use of chloramine-T on a variety of fish species. An attribute of a therapeutic aquaculture drug that must be characterized before the FDA approves its use is depletion of the drug’s marker residue (the drug’s parent compound or metabolite of highest concentration in an edible tissue). para-Toluenesulfonamide (p-TSA) is the primary degradation product and marker residue for chloramine-T in rainbow trout. To conduct residue depletion studies for chloramine-T in fish, a robust analytical method sensitive and specific for p-TSA residues in edible fillet tissue from a variety of fish was required. Homogenized fillet tissues from rainbow trout (Oncorhynchus mykiss), walleye (Stizostedion vitreum), and channel cattish (Ictalurus punctatus) were fortified at nominal p-TSA concentrations of 17, 67, 200, 333, and 1000 ng/g. Samples were analyzed by isocratic reversed-phase liquid chromatography (LC) with absorbance detection at 226 nm. Mean recoveries of p-TSA ranged from 77 to 93.17%; relative standard deviations ranged from 1.5 to 14%; method quantitation limits ranged from 13 to 18 ng/g; and method detection limits ranged from 3.8 to 5.2 ng/g. The LC parameters produced p-TSA peaks without coelution of endogenous compounds and excluded chromatographic interference from at least 20 chemicals and drugs of potential use in aquaculture.
Confirmatory Test Results on Milk from Commercial Sources that Tested Positive by ß-Lactam Antibiotics Screening Tests
Authors: Moats William A 
Published: February 2020

Abstract
U.S. Department of Agriculture, Agricultural Research Service, Meat Science Research Laboratory, Beltsville, MD 20705 Fifty-four milk samples from commercial sources that tested positive for β-lactam antibiotics were analyzed by a multiresidue liquid chromatographic (LC) procedure based on LC fractionation. Penicillin G and cephapirin were the β-lactam antibiotics found most frequently. Some samples did not contain detectable β-lactam antibiotics. In a few, the presence of a β-lactam antibiotic was suspected because certain LC fractions tested positive for antimicrobial activity, which was no longer present in a replicate treated with β-lactamase. However, the unknowns could not be identified by LC analysis.
Identification of Shark Species by Polyacrylamide Gel Isoelectric Focusing of Sarcoplasmic Proteins
Authors: Weaver LaShawn A , Lundstrom Ronald C , Colbert A Ann 
Published: February 2020

Abstract
Isoelectric focusing of muscle proteins is a fast and highly reproducible technique that has been used to identify fish species. Application of isoelectric focusing of sarcoplasmic proteins is described for identification of shark species. Sarcoplasmic protein patterns from muscle tissue of single individuals from 26 shark species and multiple individuals from 2 of the 26 shark species are shown on 1 mm thick polyacrylamide gels. Eight of these species showed pattern polymorphisms in major and minor bands; however, no individual within a species displayed the same protein pattern as that in any other species. Protein banding patterns of each species were visually distinguishable, and patterns generated on the basis of defined parameters were analyzed by a computer to obtain isoelectric points of bands, to produce schematic representations of banding patterns, and to distinguish between species-specific patterns. Isoelectric focusing appears to be an excellent method for identifying sharks. Additionally, isoelectric focusing of muscle proteins is readily applicable as a forensic tool to identify the species of shark samples received as evidence for law enforcement actions supporting shark fishery management plans.
An Immunoassay Method for Rapid Detection of Staphylococcus aureus in Cosmetics, Pharmaceutical Products, and Raw Materials
Authors: Hughes Denise , Dailianis Angela , Hill Louise 
Published: February 2020

Abstract
The TECRA Staphylococcus aureus Visual Immunoassay allows a presumptive positive or negative result for the presence of S. aureus to be obtained within 26 h, in contrast to 4-5 days by traditional cultural methods. Presumptive positive immunoassay results are confirmed by streaking the enrichment broth onto conventional agar media. A validation study was undertaken to compare the TECRA assay with a cultural reference method based on the Bacteriological Analytical Manual (8th Ed.), which is also consistent with U.S. Pharmacopoeia requirements. The products tested included a range of cosmetics (toothpaste, shampoos, conditioners, sunscreens, moisturizers, lip and eye creams) and pharmaceuticals (cough mixtures, laxatives, ulcer treatments, infant formulae, antiseptic cream), as well as some pharmaceutical ingredients. Samples were inoculated with S. aureus at 10-20 cfu/g, and then enriched for 24 h at 35°-37°C at a product-to-sample ratio of 1:100. Two different enrichment broths were used for the study: Tryptone Soya Broth with 4% Tween 80 and Modified Letheen Broth. For both enrichment broths, results of the immunoassay and the reference method showed close correlation. The TECRA S. aureus Visual Immunoassay provides a rapid and convenient alternative to cultural methods and provides advantages to industry, such as greater speed of product and ingredient release and faster tracing of contamination problems. Because the immunoassay may be read either visually or with the aid of a plate reader, there is no need for an initial outlay on capital equipment. However, the assay can be automated if required.
Determination of Emamectin Benzoate in Medicated Fish Feed
Authors: Farer Leslie J , Hayes John , Rosen Jack , Knight Peter 
Published: February 2020

Abstract
A method was developed to quantitate emamectin benzoate in fish feed at levels between 5 and 15 ppm. The active ingredient is extracted from 20 g medicated feed into aqueous-methanolic solvent by overnight shaking. A solid-phase extraction procedure using a 2 g C18 cartridge is then used to concentrate the active residue and remove interfering matrix components. The extracted drug and internal standard are eluted from the cartridge, evaporated to dryness, and reconstituted in methanol. A control feed sample and fortified control working standard are simultaneously prepared. Remaining interferences and sample analysis are further separated on a gradient liquid chromatographic system. Recovery of emamectin benzoate from fortified feeds ranged from 97 to 100%, with a coefficient of variation (CV) of 1.2%. Determination of emamectin benzoate in medicated feeds resulted in CVs ranging from 2.3 to 4.2% and recoveries of 88 to 98% of label claim.
Multiresidue Determination of Abamectin, Doramectin, Ivermectin, and Moxidectin in Milk Using Liquid Chromatography and Fluorescence Detection
Authors: Schenck Frank J , Lagman Lawrence H 
Published: February 2020

Abstract
Abamectin, doramectin, ivermectin, and moxidectin are macrocyclic lactones derived from soil dwelling actinomycetes, and are very effective against nematode, insect, and arthropod infestations. These compounds, known as endectocides, have been approved for use in beef cattle in the United States; however, they are currently not approved for use in dairy cattle. Abamectin, doramectin, ivermectin, and moxidectin residues were isolated from milk by a series of liquid-liquid extraction steps, derivatized with trifluoroacetic anhydride, and determined by liquid chromatography with fluorescence detection. Recovery studies were performed in 2 laboratories. Recoveries of &gt;80%(1-30 ng/mL) were achieved for all 4 compounds.
Determination of Amoxicillin in Trout by Liquid Chromatography with UV Detection after Derivatization
Authors: Sørensen Lambert K , Hansen Heļga , Snor Lena 
Published: February 2020

Abstract
A liquid chromatographic (LC) method based on solid-phase extraction was developed for determination of amoxicillin in muscle tissue of rainbow trout. The compound was extracted in an aqueous solution by precipitation of organic material with a mixture of sulfuric acid and sodium tungstate. The extract was processed by solid-phase extraction on an end-capped phenyl sorbent, and concentrated on a divinylbenzene-co-ΛN-vinylpyrrolidone polymeric sorbent. The extract was derivatized and analyzed by reversed-phase gradient LC on a C18 column with UV detection at 323 nm. The method detection limit was 2.9 μg/kg. Mean recovery in muscle was 80.5% (range 10-200 μg/kg). The method was applied to fillets from trout offered feed containing amoxicillin in an aquaculture pilot plant. Amoxicillin was detected in muscle tissue shortly after administration but not 3 weeks later. The relative repeatability standard deviation for incurred residues in muscle tissue was 6.4% (range 11-143 μg/kg).
Mass Peak Profiling from Selected-Ion Recording Data as a Tool for Regulatory Analyses
Authors: Grange Andrew H , Sovocool G Wayne 
Published: February 2020

Abstract
Identification of compounds in mixtures of environmental contaminants or synthetic products is essential for regulatory analyses. Exact masses of ions determined by high resolution mass spectrometry provide unique elemental compositions only for low-mass ions (&lt;150 Da). Using mass peak profiling from selected-ion recording data (MPPSIRD) to acquire additional mass spectral data and a profile generation model (PGM) for automated interpretation of the data, provides elemental compositions for ions with m/z up to 600, based on incontestable properties of atoms, their exact masses, isotopic abundances, and valences. In this study, MPPSIRD and a PGM were used to identify intended and unintended products resulting from attempted syntheses of 2 thermolabile, nonionic, phosphorothioate compounds. The products were volatilized from a probe inserted into a VG70-250SE double-focusing mass spectrometer. High mass resolution substituted separation in the mass domain for the temporal separation of most components provided by chromatographic techniques. MPPSIRD and the PGM identified the correct composition for M+• by rejecting all other compositions that were possible within the error limits of the exact mass determinations for M+• MPPSIRD was used with 10 000-24 000 resolution to determine exact masses of ions prominent in mass spectra and to isolate signals from different ions with the same nominal mass. Superposition of volatilization peaks of ions and linked scans (constant magnetic field to electrostatic sector voltage ratio) correlated fragment ions with the molecular ion. The PGM determined the compositions of fragment ions, using the number of atoms of each element in the molecular ion as limits. Fragmentation schemes based on these ions and the tables of exact masses and relative abundances provided a preponderance of evidence for the product identities.
Kuwait's Total Diet Study: Dietary Intake of Organochlorine, Carbamate, Benzimidazole and Phenylurea Pesticide Residues
Authors: Sawaya Wajih N , Al-Awadhi Fawzia A , Saeed Talat , Al-Omair Ali , Ahmad Nissar , Husain Adnan , Khalafawi Sherif , Al-Omirah Husam , Dashti Basma , Al-Amiri Hanan , Al-Saqer Jameela 
Published: February 2020

Abstract
The State of Kuwait in cooperation with the U.S. Food and Drug Administration (FDA) conducted a Total Diet Study (TDS) to estimate intakes of pesticide residues by the population. The levels of organochlorine (OC) pesticides, carbamates, benzimidazoles, and phenylureas in the TDS core list are reported here. The TDS core list was established through a national food consumption survey. All food items (140 for the Kuwaiti adult) were prepared as eaten and analyzed for the pesticides mentioned above. The FDA's multiresidue methods in Volume I of the Pesticide Analytical Manual were used in gas, liquid, and gel permeation chromatographic analyses. Only vegetable and fruit samples contained pesticide residues (mg/kg), including the carbamates 1-naphthol (1.4) and 3H-carbofuran (0.94) in carrots; the OC pesticide vinclozolin (0.47), 3H-carbofuran (0.66), and fenuron (0.6) in kiwi fruit; the OC pesticide procymidone (0.32) and carbendazim (0.5) in grapes; 3H-carbofuran (5.0) in apricots; the OC pesticides captan (0.013) and thiabendazole (0.63) in pears; captan (0.035) in plums; and carbendazim (0.4) in mandarin oranges. The levels of 3H-carbofuran found in both apricots and kiwi fruit exceeded the maximum residue limits (MRLs) of the Food and Agriculture Organization/World Health Organization (FAO/WHO) of the United Nations. The daily intakes of pesticides by the different population groups are discussed in light of the FAO/WHO acceptable daily intakes.
Analysis of Interlaboratory Performance in the Determination of Total Selenium in Water
Authors: Steinhoff Peter J , Smith Brain W , Warner Dewey W , Möller Gregory 
Published: February 2020

Abstract
This study explored the performance of experienced laboratories in the analysis for total selenium in water by a variety of analytical methods. The goal of the study was to examine intra- and interlaboratory variability. Replicates (n = 7) of 7 sample types that included a reference material of known Se concentration, natural waters, and treated wastewaters were submitted to 7 laboratories with prequalified Se analytical experience. Results of the study indicated wide ranges in minimum and maximum results, distinct differences in laboratory precision, and routine reporting of numerical results below statistical limits of quantitation. Hydride generation as a sample introduction technique demonstrated superior performance. In general, the study supports a caution advisory about using low-level Se data, especially results lower than about 10 µg Se/L, without quantitating the statistical uncertainty of the data. Because this study used data from samples that were submitted in bulk to participating laboratories prequalified for Se analytical expertise and experience, it can be considered a best-case demonstration of performance.