Enhancement Of Room-temperature Phosphorescence Research Articles

Selective enhancement of room temperature phosphorescence using cyclodextrin-treated cellulose substrate

The selective enhancement of room temperature phosphorescence (RTP) for a wide variety of polynuclear aromatic hydrocarbons (PNAs) on cyclodextrin-treated filter paper was investigated. Filter paper substrates were treated by simple impregnation in saturated solutions of ..cap alpha.., ..beta.., and ..gamma..-cyclodextrins. The results show different RTP enhancement factors for PNAs depending on the type of cyclodextrin (CD) used and on the binding strength between the cyclodextrin and the PNAs. A two-component mixture of PNAs was analyzed by RTP and synchronous RTP in order to illustrate the improved sensitivity of the RTP technique and demonstrate the selective enhancement by cyclodextrin (SCED) methodology in multicomponent analysis.

Enhanced Room-Temperature Phosphorescence of Anthracene on Cyclodextrin-Treated Filter Paper

This study investigates the enhancement of room-temperature phosphorescence (RTP) for anthracene when the compound is adsorbed on cyclodextrin (CD)-treated filter paper. The results show that β-CD treatment induces a significant increase in anthracene RTP emission, which is normally extremely weak. The α-CD does not produce any strong RTP enhancement, while γ-CD produces relatively lower enhancement than does β-CD. The CD treatment procedure is very simple and improves the analytical usefulness of the RTP method. The binding constants of anthracene to cyclodextrin were measured with the use of thin-layer chromatographic retention values. Anthracene has a higher binding constant with β-CD than with γ-CD, in agreement with the RTP enhancement results.