0000000000041564
AUTHOR
Diana Dzabijeva
Rugged Large Volume Injection for Sensitive Capillary LC-MS Environmental Monitoring
A rugged and high throughput capillary column (cLC) LC-MS switching platform using large volume injection and on-line automatic filtration and filter back-flush (AFFL) solid phase extraction (SPE) for analysis of environmental water samples with minimal sample preparation is presented. Although narrow columns and on-line sample preparation are used in the platform, high ruggedness is achieved e.g. injection of 100 non-filtrated water samples would did not result in a pressure rise/clogging of the SPE/capillary columns (inner diameter 300 µm). In addition, satisfactory retention time stability and chromatographic resolution were also features of the system. The potential of the platform for …
Chemical Composition Analysis, Antimicrobial Activity and Cytotoxicity Screening of Moss Extracts (Moss Phytochemistry)
Mosses have been neglected as a study subject for a long time. Recent research shows that mosses contain remarkable and unique substances with high biological activity. The aim of this study, accordingly, was to analyze the composition of mosses and to screen their antimicrobial and anticancer activity. The total concentration of polyphenols and carbohydrates, the amount of dry residue and the radical scavenging activity were determined for a preliminary evaluation of the chemical composition of moss extracts. In order to analyze and identify the substances present in mosses, two types of extrahents (chloroform, ethanol) and the GC/MS and LC-TOF-MS methods were used. The antimicrobial activ…
Anti-Bacterial Activity and Online HPLC-DPPH Based Antiradical Kinetics of Medicinal Plant Extracts of High Relevance for Cosmetics Production
The present study provides an assessment of extracts of six medicinal plants for their applicability in cosmetic formulations aimed at anti-UV protection and anti-acne treatment. Ethanol extracts of Chelidonium majus L., Myrtus communis L., Hamamelis virginiana L., Juniperus communis L., Alchemilla vulgaris and Ilex paraguariensis are analysed for the phytochemical content, antimicrobial activity, antiradical activity and antiradical kinetics. The phytochemical composition of the plants is investigated by LC-MS analysis and the most active antioxidants in plant extracts are determined by online HPLC-DPPH assay. The kinetic parameters of the antiradical reaction are determined both for the s…
Multi-technique approach for qualitative and quantitative characterization of furazidin degradation kinetics under alkaline conditions
Degradation of drug furazidin was studied under different conditions of environmental pH (11-13) and temperature (30-60°C). The novel approach of hybrid hard- and soft-multivariate curve resolution-alternating least squares (HS-MCR-ALS) method was applied to UV-vis spectral data to determine a valid kinetic model and kinetic parameters of the degradation process. The system was found to be comprised of three main species and best characterized by two consecutive first-order reactions. Furazidin degradation rate was found to be highly dependent on the applied environmental conditions, showing more prominent differences between both degradation steps towards higher pH and temperature. Complim…
CCDC 910846: Experimental Crystal Structure Determination
Related Article: Kārlis Bērziņš, Artis Kons, Ilze Grante, Diana Dzabijeva, Ilva Nakurte, Andris Actiņš|2016|J.Pharm.Biomed.Anal.|129|433|doi:10.1016/j.jpba.2016.07.039
CCDC 910834: Experimental Crystal Structure Determination
Related Article: Kārlis Bērziņš, Artis Kons, Ilze Grante, Diana Dzabijeva, Ilva Nakurte, Andris Actiņš|2016|J.Pharm.Biomed.Anal.|129|433|doi:10.1016/j.jpba.2016.07.039