RESUMO
A new ultra HPLC (UHPLC) method using both MS and fluorescence detection (FD) was developed for the determination of five fluoroquinolones in wastewaters. Systematic method development approach was compared with a conventional one. During the systematic approach, a possibility of automatic switching among four independent analytical columns of different chemistries has been used. Acidic as well as basic pH using ACN and methanol as organic modifiers was tested. The best separation of fluoroquinolones was obtained on phenyl analytical column at pH 10.5, which is a completely novel approach for separation of fluoroquinolones. Further, a new SPE procedure was developed for the sample preparation using basic pH as well. The sensitivity and selectivity of FD and MS detection were compared. FD at basic pH 10.5 demonstrated lower sensitivity than at acidic pH, which is conventionally performed. At basic pH, UHPLC-MS/MS was found about two orders of magnitude more sensitive than FD. Both methods were validated and subsequently UHPLC-FD method was used for the evaluation of stability of fluoroquinolones. UHPLC-MS/MS method was used for the analysis of wastewater samples. Norfloxacin and ciprofloxacin were detected in samples of influent and effluent from wastewater treatment plant. Ofloxacin was detected only in influent from wastewater treatment plant.
Assuntos
Antibacterianos/análise , Cromatografia Líquida de Alta Pressão/métodos , Fluoroquinolonas/análise , Espectrometria de Massas/métodos , Esgotos/química , Espectrometria de Fluorescência/métodos , Poluentes Químicos da Água/análise , Animais , Cromatografia Líquida de Alta Pressão/instrumentação , Humanos , Espectrometria de Massas/instrumentação , Estrutura Molecular , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Fluorescência/instrumentaçãoRESUMO
Total phenolic content, reducing power, antioxidant and free radical scavenging activities of ethanol extracts of five mosses were determined in vitro. No correlation between the total phenolic content and antioxidant or scavenging activities was found.
Assuntos
Antioxidantes/farmacologia , Briófitas/classificação , Fitoterapia , Extratos Vegetais/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/uso terapêutico , Compostos de Bifenilo , Sequestradores de Radicais Livres/administração & dosagem , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/uso terapêutico , Radicais Livres/química , Humanos , Concentração Inibidora 50 , Óxido Nítrico/química , Picratos/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêuticoRESUMO
The thiophene polyacetylene (E)-1-[5-(hept-5-en-1,3-diynyl)-2-thienyl]ethan-1,2-diol, isolated from the roots of Leuzea carthamoides, showed phototoxic activity in the assay systems of histidine photo-oxidation, Artemia and Tubifex assays. The effects were compared with the standard photosensitizer xanthotoxin.
