Estudo da retenção de vitaminas lipossolúveis e hidrossolúveis empregando cromatografia com fluído supercrítico de ultra alta eficiência e desenvolvimento de métodos de acordo com os conceitos de analytical quality by desing  

Abstract

The objective of this work was to describe the retention and separation of the major fat soluble and water soluble vitamins in the Ultra High Performance Supercritical Fluid Chromatography (UHPSFC) technique as a function of the main experimental factors involved and to use the concepts of Analytical Quality by Design for the development of analytical methods. Initially, through a screening study, the stationary phases Acquity HSS C18 SB and Acquity Torus 2-PIC were identified as the most promising along with methanol as the organic modifier of the mobile phase and ammonium formate (10 mmol L -1 ), water (5%) and ammonium hydroxide (10 mmol L -1 ) as additives, which were mandatory for the improvement of chromatographic parameters for water soluble vitamins. Then, a Central Composite Design was performed to study the variables that influence the fluid density: percentage of organic modifier at the end of the gradient, counter-pressure and temperature. The evaluated responses were: retention factor (k), number of plates (N), asymmetry (As), area of the peaks and resolution (Rs). The multivariate study showed that the three factors influenced in a different way each analytical response and allowed, by means of desirability functions, the construction of the Design Space, which is the region where robustness and adequacy of the parameters of the chromatographic method are guaranteed. All vitamins presented analytical responses (areas) directly proportional to the concentration, with r > 0.99. In the analysis of a pharmaceutical soft capsule, no interferences of the matrix and the diluent were detected.Palavras-chave: Vitamins, Ultra high performance supercritical fluid chromatography (UHPSFC), Analytical Quality by Design (A-QbD).

Técnicas De Identificação Química De Metabólitos Produzidos Por Microrganismos Endofíticos

“…A CFS tem se mostrado uma técnica muito vantajosa pois apresenta menor consumo de solvente orgânico, maior estabilidade dos analitos termicamente instáveis, pois existe a possibilidade de utilizar baixas temperaturas (utilização de CO 2 ), além de apresentar um tempo curto de análise devido à baixa viscosidade e a possibilidade do aumento das vazões da fase móvel (BRUHN, 2018).…”