How to obtain higher efficiency with superficially porous particles in HPLC
Santos Neto, Álvaro José
Palavras-chave: HPLC, UHPLC, superficially porous particles, extra-column volume, efficiency, instrumentation.
Resumo: Recent developments in liquid chromatography have enabled faster and more efficient separations. We can cite the recent introduction of UHPLC systems (Ultra-High Performance Liquid Chromatography) with the use of columns packed with sub-2 μm porous particles, as well as the development of columns with sub-3 μm superficially porous particles, which are not strictly restricted to the use of a UHPLC system. Although columns with sub-3 μm superficially porous particles exhibit almost the same efficiency of those with sub-2 μm totally porous particles, under considerably lower backpressure, the use of a non-optimized HPLC system can hinder part of that performance. This article depicts implications related with the use of a non-optimized conventional HPLC system when sub-3 μm superficially porous particles columns are employed. Furthermore, procedures for optimizing a conventional HPLC are described in order to obtain performance similar to those of UHPLC systems, when using the above mentioned sub-3 μm stationary phases.
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