Authors:Stefano Dugheri, Alessandro Bonari, Ilenia Pompilio, Marco Colpo, Nicola Mucci, Manfredi Montalti, and Giulio Arcangeli
Development of an Innovative Gas Chromatography—Mass Spectrometry Method for Assessment of Formaldehyde in the Workplace Atmosphere
S. Dugheri et al.
Formaldehyde (FA), a colorless gaseous
Authors:D. Krasucka, C. Kowalski, M. Osypiuk, and G. Opielak
A high-performance liquid chromatographic (HPLC) method with fluorescence detection after precolumn formaldehyde derivation was developed to detect concentrations of amoxicillin (AMX) in poultry plasma. Proteins in plasma samples spiked with AMX were precipitated with a phosphate buffer and trichloroacetic acid. After precolumn treatment of the extraction product of AMX with formaldehyde under acidic and heating conditions, HPLC analysis with fluorescence (FL) detection at an excitation wavelength of 355 nm and an emission wavelength of 450 nm was performed. A mobile phase comprising acetonitrile and a buffer solution (0.05 M KH2PO4 pH = 5.6), which yielded AMX retention time 8.58 min, was suitable for detection of AMX. The calculated standard curve of the reaction product was linear, and the correlation coefficient was greater than 0.999. The limit of detection and quantification, the accuracy, and the precision were evaluated. Recoveries of spiked amoxicillin were >92%, with a coefficient of variation in the range of 0.35–0.89%. This method has been successfully applied to a pharmacokinetic study after oral administration of amoxicillin to poultry.
Authors:N. Akhtar, Md. Faiyazuddin, G. Mustafa, Y. Sultana, S. Baboota, and J. Ali
Formaldehyde in aquatic products was determined by micellar electrokinetic capillary chromatography (MEKC) after derivatization with 2,4-dinitrophenylhydrazine. Separation was carried out at 25 °C and 25 kV, using a fused silica capillary (75 µ internal diameter; 50.5 cm effective length) and an ultraviolet detector set at 360 nm. The optimal background electrolyte was 20 mM sodium tetraborate and 20 mM sodium dodecyl sulfate at pH 9.0 with 3 s hydrodynamic injection at 30 mbar. Electrophoretic analysis took approximately 6.5 min. The correlation coefficient of the calibration curve was 0.999 over the concentration range 2.0–100.0 mg L−1, and the LOD and LOQ values were 0.57 and 1.89 µg mL−1, respectively. The recoveries were from 83.7% to 97.2% with steam distillation as the sample pretreatment method.
Authors:Dominique Roberge, Christian Noti, Eberhard Irle, Markus Eyholzer, Bruno Rittiner, Gerhard Penn, Gottfried Sedelmeier, and Berthold Schenkel
After a short section of safety aspects related to 2-nitroethanol, the paper describes a powerful methodology for developing flow processes based on a proof of concept (1), an optimization and modeling analysis (2), and a long run study in a mini-plant (3). The proof of concept is the initial stage where the solubilities and concentrations are fixed, taking into account the rough kinetics with a mass transfer understanding. It is followed by a complete kinetic analysis including activation energy to model the reaction under various conditions to optimize different targets (yield not being the only driver!). The last section shows the operation of a mini-plant including a microreactor and work-up unit operations. The approach is extremely powerful as it enables the study at laboratory scale of all the features that are usually associated with a pilot plant namely: stability over time on stream, solvent recirculation, model prediction, and robustness.
Authors:Dariusz Szychowski, Barbara Pacewska, Grzegorz Makomaski, Janusz Zieliński, Wiesława Ciesińska, and Tatiana Brzozowska
among organic substances are both chemical compounds of defined composition, like acenaphthene, naphthalene, formaldehyde, alcohols, and mixtures of organic substances, for instance olefins and industrial waste [ 1 – 7 ].
Chemical composition of
Authors:Grzegorz Makomaski, Wiesława Ciesińska, and Janusz Zieliński
. An attempt was made to determine the influence of PET or phenol-formaldehyde resin (PF) addition on thermal properties of CTP as well as AC obtained from pitch-polymer compositions.
The raw materials
Authors:SKM. Pothinathan, M. Muthukannan, N. Selvapalam, and S. Christopher Gnanaraj
polymers to overcome negative marks of the polymers available on the market. This study aims to use a new polymer named glycoluril-formaldehyde resin as a modifying agent to prepare high-strength concrete. Formaldehyde-based additives are not a new part of