Determination of critical micelle concentrations and aggregation numbers by fluorescence correlation spectroscopy: aggregation of a lipopolysaccharide.
Anal Chim Acta
; 556(1): 216-25, 2006 Jan 18.
Article
em En
| MEDLINE
| ID: mdl-17723352
ABSTRACT
Fluorescence correlation spectroscopy (FCS) is often used to determine the mass or radius of a particle by using the dependence of the diffusion coefficient on the mass and shape. In this article we discuss how the particle size of aggregates can be measured by using the concentration dependence of the amplitude of the autocorrelation function (ACF) instead of the temporal decay. We titrate a solution of aggregates or micelles with a fluorescent label that possesses a high affinity for these structures and measure the changes in the amplitude of the ACF. We develop the theory describing the change of the ACF amplitude with increasing concentrations of labels and use it to fit experimental data. It is shown how this method can determine the aggregation number and critical micelle concentration of a standard detergent nonaethylene glycol monododecyl ether (C12E9) and a lipopolysaccharide (LPS Escherichia coli 0111B4).
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Anal Chim Acta
Ano de publicação:
2006
Tipo de documento:
Article
País de afiliação:
Singapura