Photocatalytic degradation of chlothianidin: effect of humic acids, nitrates and oxygen
T16N1
M.B. Kralj, E.G. Dilcan, G. Salihoğlu, D.M. Mazur, A.T. Lebedev, P. Trebše
The use of neonicotinoid insecticides has been constantly revised due to their impact on bees causing their decrease and bee malady. Unfortunately, because of the worldwide differences in pesticide regulation, chlothianidin is still allowed in European Union for greenhouse use and worldwide in some cases without any restictions. Lately, it was detected, on soil particles, in raw and drinking waters. The preparation of drinking waters implies different purification processes, including chlorination, ozonation, UV irradiation and nowadays advanced oxidation processes including TiO2. The TiO2 photocatalytic degradation of chlothianidin in the presence of oxygen, nitrate and humic acids was followed by kinetic studies, whereas the photoproducts formed were identified using liquid chromatography/tandem mass spectrometry. The efficiency of different set-ups of photocatalytic degradation of chlothianidin was evaluated by identification of photoproducts and bioluminescence inhibition of bacteria Vibrio fischeri. The results indicated that the less harmful photoproducts are generated in the samples with added humic acids.
Identification of regions in apomyoglobin which form intermolecular interactions in amyloid aggregates using high-performance mass spectrometry
T13N4
N.S. Katina, M.Yu. Suvorina, E.I. Grigorashvili, V.V. Marchenkov, N.A. Ryabova, A.D. Nikulin,
A.K. Surin
Formation of amyloid aggregates in human organs and tissues causes the development of incurable diseases. However experimental studies of the mechanism of amyloid formation by proteins as well as structural characteristics of amyloids are complicated because of heterogeneity and high molecular weight of the aggregates. We have used limited proteolysis and mass spectrometry for identification of regions in the polypeptide chain of apomyoglobin which give rise to intermolecular interactions in amyloid structures. The methods of tandem mass spectroscopy have allowed us to identify regions in the polypeptide chain of myoglobin which form the core of amyloid structures. It is shown that the main structural elements for the formation of the core of amyloid fibrils in myoglobin are regions from amino acid region 60 through 90 and from 97 through 124. These areas coincide well with the theoreticall prediction. The approach has made it possible to obtain important data on the structure of protein molecules in aggregates and on conformational rearrangements of apomyoglobin upon amyloid formation.
Non-target screening of markers of synthetic cannabinoids in urine using HPLC-MS/MS
T12N1
Non-target screening of markers of synthetic cannabinoids in urine
using HPLC-MS/MS
A.V. Labutin, A.Z. Temerdashev
(Русский) Определение тритерпеноидов коры березы методом жидкостной тандемной хроматомасс-спектрометрии
Sorry, this entry is only available in Русский.
