Cromatografia líquida capilar: 2. Alargamento das bandas por efeitos extracoluna

Coutinho, Lincoln F. M.; Lanças, Fernando M.

Palavras-chave: Cromatografia líquida capilar, alargamento de bandas, fatores extra coluna, micro LC, LC capilar.

Resumo: O alargamento da banda é um fator altamente indesejável em todas as técnicas cromatográficas, uma vez que diminui a eficiência da coluna (menor número de pratos, N) e deteriora a resolução (menor Rs). Este efeito é particularmente crítico na cromatografia líquida capilar (c-LC) devido aos pequenos volumes da instrumentação, conexões, colunas, etc., empregados na técnica. Como parte de uma série de artigos a respeito da c-LC, neste trabalho serão abordados os principais fatores que ocasionam o alargamento das bandas cromatográficas em c-LC, assim como a maneira de evitá-lo.

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