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A simple, accurate, precise, rapid and sensitive capillary zone electrophoresis (CZE) method was developed, optimized and validated for the simultaneous determination of strontium ranelate (antiosteoporetic drug) and aspartame (sweetener excipient) in pharmaceutical formulation for the treatment of postmenopausal osteoporosis. The final optimized conditions obtained were: borate buffer 50 mmol L-1 at pH 9.4 (BGE), applied potential of 30 kV, temperature set to 35 °C and hydrodynamic injection time of 10 s at a pressure of 50 mbar. The separation was carried out into a fused-silica capillary column (55 cm total length × 75 μm ID) and took less than 8 min. A diode array detector was used for the detection of the anion ranelate and aspartame at 235 and 198 nm, respectively. For both analytes, the method showed linear range from 1 to 40 μg mL-1, with satisfactory detectability (limits of detection of 0.3 and 0.2 μμg mL-1 for aspartame and ranelate, respectively). In addition, acceptable accuracy, good repeatability and intermediate precision (RSD < 2.6%) were obtained. The feasibility of the method was verified with recovery tests of analytes in the pharmaceutical sample. Recoveries varied from 85 ± 5% to 111 ± 2%, indicating the usefulness and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work was to quantify the biopolymers associated to esterase enzymes and identify bacterial respiratory activity in four cores collected in Suruí Mangrove, Guanabara Bay – RJ. Biopolymer concentration was 1000 times lower than previously reported in the literature, indicating the need for creating and establishing eutrophication indicative rates and records compatible with tropical coastal systems. The biochemical representative relationships in the cores were equivalent to those from studies on coastal marine environments made in the Northern Hemisphere. The esterase enzymes in the sediment proved efficient in the mineralization of biopolymers, even with preferentially anaerobic metabolic physiology. Despite the lack of incipient geomicrobiological studies, the results highlighted the possible application of microbiology to a better understanding of geological processes. [ABSTRACT FROM AUTHOR]

Highlights • Five macrocyclic lactones were studied in cheese that is a very complex food matrix. • An analytical method was developed and validated, following international guidelines. • Excellent figures of merit were obtained with very low limits of quantification. • Twenty-one of the twenty-two cheeses studied contained macrocyclic lactones. • This is the first simultaneous evaluation of five macrocyclic lactones in cheeses. Abstract A highly sensitive analytical method was developed and validated, following international guidelines, for the determination of the residues of five macrocyclic lactones (MLs) (abamectin, doramectin, eprinomectin, ivermectin and moxidectin) in cheese. The extracts were concentrated by rotary-evaporation and derivatized; no clean-up was necessary. Despite matrix complexity, no significant matrix-effect was verified, and standards were prepared in solvents. Linear working ranges varied from 0.25 to 5.0 μg L−1. Excellent limits of quantification (0.58–0.87 μg kg−1), mean recoveries (91–103%), and repeatability and intermediate precision (<5.8%) were obtained. Twenty-two samples of bovine and non-bovine cheeses were analyzed. Twenty-one samples showed residues of at least one ML (between 0.59 and 15.3 μg kg−1), but moxidectin was never detected; a sample of mozzarella was free of MLs. To the best of our knowledge, this is the first method describing the simultaneous evaluation of these MLs in cheese using HPLC and fluorescence detection. [ABSTRACT FROM AUTHOR]

The interest in charcoal for agricultural use (biochar) has sharply increased in recent years. However, biochar can contain groups of compounds such as polycyclic aromatic hydrocarbons (PAHs) that are considered persistent pollutants, and are formed concomitantly with biochar during its production by pyrolysis. Soil samples were collected in three experimental areas at different intervals (1, 3, 5 or 6 years) after the application of 16 Mg ha −1 of biochar. The total concentrations of PAHs; benzo[ a ]pyrene; and the estimated total cancer risk in biochar treated plots were larger than found in the control ones, but they decreased over time, equaling the control values after three years in the high C content soil (11.2 g C kg −1 soil), or after six years in the low C content soil (6.8 g C kg −1 soil). Nevertheless, the sum of PAH concentrations found in the biochar amended plots, in the range of 15.80–39.40 ng g −1 , were around two orders of magnitude below the limits of prevention established by Brazilian legislation (8100 ng g −1 ) and some European regulations for soils (3000 ng g −1 ) and also lower than the observed in previous studies about biochar amended soils. Our results indicate that, under the conditions evaluated, the application of biochar to soil in the studied proportion (16 Mg ha −1 , every six years) is safe concerning soil contamination by PAHs. [ABSTRACT FROM AUTHOR]

Reliable analytical results are necessary to ensure effective consumer protection and the use of certified reference material (CRM) is an important tool for quality assurance. The Brazilian Metrology Institute (Inmetro) studied the feasibility of the production of a candidate CRM of chloramphenicol (CAP) in milk. CAP is an antibiotic banned for treatment of food-producing animals. A minimum required performance limit (MRPL) for analytical methods of 0.3 μg kg −1 was set by the European Community for the detection of CAP residues in food matrices. Liquid chromatography with isotope dilution mass spectrometry (LC–IDMS) was employed for CAP determination and water content was measured by Karl Fischer coulometric titration. The feasibility study showed milk powder processed with both spray dryer and lyophilization lead to the best results, showing good degree of inhomogeneity for CAP residues (5.0%) and for water content (3.0%), therefore demonstrating that the production of this candidate CRM was feasible. [ABSTRACT FROM AUTHOR]

An analytical method was developed and validated for the simultaneous determination of four macrocyclic lactones (ML) (abamectin, doramectin, ivermectin and moxidectin) in butter, using liquid chromatography with fluorescence detection. The method employed heated liquid–liquid extraction and a mixture of acetonitrile, ethyl acetate and water, with preconcentration and derivatization, to produce stable fluorescent derivatives. The chromatographic run time was <12.5 min, with excellent separation. The method validation followed international guidelines and employed fortified butter samples. The figures of merit obtained, e.g. recovery (72.4–106.5%), repeatability (8.8%), within-laboratory reproducibility (15.7%) and limits of quantification (0.09–0.16 μg kg −1 ) were satisfactory for the desired application. The application of the method to real samples showed that ML residues were present in six of the ten samples evaluated. The method proved to be simple, easy and appropriate for simultaneous determination of ML residues in butter. To our knowledge, this is the first method described for the evaluation of ML in butter. [ABSTRACT FROM AUTHOR]

A method of high performance liquid chromatography with fluorescence detection (HPLC-Fluo), based on previous studies of the natural fluorescence emission of melamine (250/365 nm), was developed and validated for melamine determination as an adulterant of bovine UHT whole milk. The clean up treatment of milk samples by deproteinization was thoroughly optimized. No matrix effect was observed and a linear range from 0.05 to 10.0 μg mL −1 was obtained, with a value of R 2 equal to 0.9998. The limits of detection and quantification of melamine were 0.0081 and 0.027 μg mL −1 respectively, or 0.023 and 0.076 μg g −1 of milk, respectively, considering the sample dilution during extraction. Extracts of milk samples fortified with melamine at three concentration levels, two of which corresponded to the levels established by WHO for melamine in foods, led to an overall mean recovery of 95.4 ± 1.2% ( n = 9). This recovery value satisfies the performance criteria established by the Codex Alimentarius for analytical methods suitable for determination of food residues, demonstrating the usefulness and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Atmospheric particulate matter (total suspended particulate – TSP – and inhalable particles – PM10) and gas-phase samples were collected in three periods of seven to nine consecutive days in June and December 2011, and May 2012, in the central area of Niterói City, Rio de Janeiro State, Brazil. TSP (48.8–214 μg m −3 ) showed higher concentrations than PM10 (nd – 82.6 μg m −3 ). Sixteen polycyclic aromatic hydrocarbons (PAH) and thirty-one carbonyl compounds (CC) were evaluated. Concentrations of individual PAH ranged from

''Krokodil'' is the street name for the homemade injectable mixture that has been used as a cheap substitute for heroin. Its use begun in Russia and Ukraine and nowadays is being spread over several other countries. Desomorphine is the semi-synthetic opioid claimed to be the main component of krokodil and considered to be responsible for its psychoactive characteristics. The starting materials for desomorphine synthesis are codeine tablets, alkali solutions, organic solvent, acidified water, iodine and red phosphorus, all of which are easily available in retail outlets, such as supermarkets, drugstores, etc. The resulting product is a light brown liquid that is called krokodil. People who inject krokodil present a great variety of serious signs and symptoms, including thrombophlebitis, ulcerations, gangrene, and necrosis, quickly evolving to limb amputation and death. These effects are thought to result from the toxic components produced as byproducts during the homemade drug synthesis. In this work, we reviewed several aspects of krokodil use, including its epidemiology, pharmacology and the chemical properties of the main active ingredient (desomorphine). To enhance our understanding of the clinical and toxic effects and to support the implementation of harm reduction measures, we also describe the ''bathtub chemistry'' of krokodil and the content of the final solution. [ABSTRACT FROM AUTHOR]

Abstract: A relatively fast method was developed and applied to the determination of selected synthetic food dyes (Sunset Yellow, Tartrazine, Amaranth, Brilliant Blue and Red-40) in three different kinds of foodstuffs: solid juice powders, solid jelly powders and soft drinks. High performance liquid chromatography with UV-DAD detection was employed. The developed chromatographic method employed an ODS Zorbax column (250mm; 4.6mm; 5μm). Two different solvent systems were employed depending on the expected dyes in the studied samples. Sample preparation consisted of dissolving and filtering the samples and showed high throughput. Adequate detection and quantification limits together with high recoveries (better than 98.8%) were obtained. All studied samples showed dye levels in conformity with Brazilian legislation. Indeed some products showed poor quality and/or production controls due to the variability between lots. This fact was more critical for Tartrazine and Sunset Yellow in solid juice powders and there is concern that these substances can exceed legislated values. It was also observed that different producers use different dyes and/or composition in similar products. [Copyright &y& Elsevier]

Here we report the variation of diterpenes from three populations of the brown alga Dictyota mertensii. The populations were analyzed by 1H NMR and GC-MS techniques. Both chemical GC-MS and 1H NMR profiles of D. mertensii presented diterpenes as major constituents. In all populations, we detected the prenylated guaiane diterpenes, dictyoxide, pachydictyol A, isopachydictyol A, dictyol B and its acetate, and dictyol C. Although dictyol H has been described as a taxonomic marker, this diterpene was found in only two of the three studied populations. This result reinforces the need for studies of temporal and geographic variation for the establishment of the taxonomic limits of the species chemical patterns. It was also possible to observe mass spectra fragmentation and proton chemical shift in the NMR spectra characteristic from xeniane diterpenes, for the first time in this species, which led to the detection of dictyodial, suggesting that D. mertensii belongs to the chemotaxonomic group of species D. ciliolata, D. jamaicensis, and D. menstrualis , all of which are producers of diterpene from chemical groups I and III. Image 1 • The diterpenes from Brazilian populations of Dictyota mertensii were studied. • D. mertensii is a producer of diterpenes group I and III. • Dictyol H may not be detectable in some populations. • The chemical and its composition might be subjected to environmental conditions. [ABSTRACT FROM AUTHOR]