HOST-GUEST ROOM TEMPERATURE PHOSPHORESCENCE OF 1-NAPHTHALENACETIC ACID INCLUDED IN β-CYCLODEXTRIN IN PRESENCE OF 1,3-DIBROMOPROPANE

Abstract

The processes of inclusion of 1-naphthalenacetic acid in β-cyclodextrin, in the presence of bromoalkanes and bromoalcohols have been studied and compared by luminiscence methods. In both cases, room temperature phosphorescence emission was observed, with higher intensity in the presence of bromoalkanes than in the presence of bromoalcohols. The deoxygenation of the solutions is necessary, in order to avoid the quenching of phosphorescence, and was achieved by flowing nitrogen, by the addition of sodium sulphite and the combination of both methods, which is the most effective approach. The presence of an excess of bromoalkane produced a turbid suspension which seems necessary to obtain phosphorescence emission from the ternary system. The room temperature phosphorescence emission obtained in the presence of 1,3-DBP has been optimized and the analytical figures of merit of the system have been evaluated.

Keywords:

• Room temperature phosphorescence
• β-CD
• 1-Naphthalenacetic acid
• 1,3-Dibromopropane

ACKNOWLEDGMENTS

The authors acknowledge the DGESIC (Proyect PB 98-0999) and the Consejería de Educación, Ciencia y Tecnología, Junta de Extremadura (Proyect IPR00C018) for financial support of this work. A. Bautista Sánchez acknowledges a fellowship from the Consejería de Educación, Ciencia y Tecnología, Junta de Extremadura (DOE 29/3/97).