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Experimental values of fluorescence quantum yield, phosphorescence quantum yield, and phosphorescence lifetime were acquired at temperatures from 23° to −180°C for the protonated form of benzo(f)quinoline adsorbed on filter paper. From the experimental values, triplet formation efficiencies, rate constants for phosphorescence, and rate constants for the radiationless transition from the triplet state were calculated. The results showed the various interrelationships of the solid-surface radiative and nonradiative processes. In addition, the results indicated that the modulus of the solid matrix is an important factor in enhancing phosphorescence quantum yield.

The solid-surface fluorescence and phosphorescence quantum yield values and phosphorescence lifetime values were obtained for p-aminobenzoic acid (PABA) and 4-phenylphenol adsorbed on α-cyclodextrin/NaCl mixtures. From the luminescence quantum yield and phosphorescence lifetime data, the triplet formation efficiency values, the phosphorescence rate constants, and the rate constants for radiationless transition from the triplet state were determined for PABA and 4-phenylphenol on α-cyclodextrin/NaCl mixtures. In addition, the percentages of radiative and nonradiative transitions were calculated for the two compounds. The various luminescence parameters obtained in this work provided important insights into the analyte/α-cyclodextrin substrate interactions responsible for the observed solid-surface room-temperature fluorescence (RTF) and phosphorescence (RTP). Furthermore, the RTF and RTP intensities of PABA and 4-phenylphenol were obtained from several α-cyclodextrin/NaCl mixtures. These data showed the importance of the initial wet chemistry in the sample preparation procedure.

Fifty-five organic compounds of various sizes and functionalities were investigated for solid-surface room-temperature fluorescence (RTF) and phosphorescence (RTP) on an 80% α-cyclodextrin-NaCl matrix. Forty-two of these compounds showed either RTP and/or RTF on this matrix. The relative RTP intensities of the compounds were compared, and the results showed that triphenylene gave the strongest RTP signal, while phenanthridine gave the weakest signal. The range of the RTP limit of detection of the phosphorescent compounds on an 80% α-cyclodextrin-NaCl mixture was determined to be between 0.2 ng and 15 ng. The results showed the general analytical potential of this approach because of the large number of compounds yielding luminescence signals and the selectivity and sensitivity achieved.