Retention behavior of β-cyclodextrin complexes of anthracene and pyrene using reversed-phase liquid chromatography: The effects of tert.-butanol and cyclopentanol

• Published in: Journal of Chromatography A 1992-03, Vol.594 (1), p.37-43
• Main Authors: Anigbogu, Vincent C., de la Peña, Arsenio Muñoz, Ndou, Thilivhali T., Warner, Isiah M.
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Chemistry; Chromatographic methods and physical methods associated with chromatography; Exact sciences and technology; Other chromatographic methods
• ISSN: 0021-9673
• DOI: 10.1016/0021-9673(92)80311-H

The effects of tert.-butanol and cyclopentanol on the formation of β-cyclodextrin (β-CD)-anthracene and β-CD-pyrene complexes have been studied using reversed-phase liquid chromatography. The retention times of anthracene and pyrene were monitored when eluted in a C 18 column with mobile phase mixtures consisting of methanol, water, β-CD, and a small amount of tert.-butanol or cyclopentanol. Plots of capacity factor of anthracene versus concentration of β-CD in the mobile phase in methanol-water mixtures and in mixtures containing 1% (v/v) cyclopentanol or tert.-butanol as secondary modifiers showed very similar trends. This suggests that anthracene forms weak complexes with β-CD, and that the presence of these secondary mobile phase modifiers have little effect on the β-CD-anthracene inclusion reaction. In contrast, pyrene showed no discernable change in retention time with increases in β-CD concentration. However, in the presence of 1% (v/v) tert.-butanol or cyclopentanol, capacity factor of pyrene decreased drastically, more in 1% (v/v) cyclopentanol than in 1% (v/v) tert.-butanol. Formation of a ternary β-CD-pyrene-alcohol complex has been proposed to explain the effects.