масс-спектрометрия

Рассмотрена возможность применения метода матрично-активированной лазерной десорбции/ионизации с время пролетным масс-анализатором для определения молекулярно-массового распределения олигомеров полиметиленнафталинсульфоновых кислот. Найдены оптимальные условия определения молекулярно-массового распределения: матрица – ?-циано-4-гидроксикоричная кислота, допант – нитрат цезия.

In this paper the high efficiency of the anionic absorbent polymer in the sorption and desorption of samples of aqueous solutions of organic substances. Recommended that the optimal conditions for use as a sorbent sample of water objects of the environment in the process of chemical and analytical monitoring of environmental pollutants of natural and anthropogenic origin.

The molecular ions fragmentation canals of substances registered by means of the GC-MS method in the media of Lentinula edodes (shiitake) basidiomycete submerged cultivation in the presence of diacetophenonylselenide have been substantiated. At the B3LYP/6-311++G(3df,3pd) and UB3LYP/6-311++G(3df,3pd) level, involving the NBO analysis and the R. F. W. Bader’s «Atoms in Molecules» quantum theory (QTAIM), isomeric transformations of dihydrofurans have been considered.

We found that under laser desorption and ionization conditions, quercetin, belonging to the flavonol family, undergoes a decay, which occurs through a photoinduced reaction followed by dimerization of the forming biradical and by the subsequent fragmentation of the dimer. Naringenin, belonging to the flavonone family, also undergoes similar fragmentation, but owing to the lack of conjugation in the C ring, the forming biradical particle is not capable of further dimerization in the same way as observed for quercetin because of its low stability.