Como obter maior eficiência com partículas superficialmente porosas em HPLC

Santos Neto, Álvaro José

Palavras-chave: HPLC, UHPLC, partículas superficialmente porosas, volume extracoluna, eficiência, instrumentação.

Resumo:  Os recentes desenvolvimentos da cromatografia líquida têm permitido separações mais eficientes e rápidas. Pode-se citar a recente introdução da UHPLC (Ultra-High Performance Liquid Chromatography), com o uso de colunas preenchidas com partículas porosas menores do que 2 μm de diâmetro (sub-2 μm), bem como o desenvolvimento de colunas com partículas superficialmente porosas sub-3 μm as quais não dependem estritamente de um sistema UHPLC. Apesar de as colunas com partículas superficialmente porosas sub-3 μm apresentarem quase a mesma eficiência daquelas com partículas sub-2 μm totalmente porosas, sob pressões consideravelmente mais baixas, o uso das primeiras em um sistema HPLC “não-otimizado” pode prejudicar parte desse desempenho. Este artigo descreve as implicações do uso de um sistema HPLC convencional sem as possíveis otimizações quando se empregam as colunas com essas fases estacionárias sub-3 μm. Ademais, são descritos os procedimentos necessários para otimizar um HPLC convencional, de maneira a se obter um desempenho próximo ao de um UHPLC ao usar essas fases estacionárias sub-3 μm.

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