Comparison of non-protected fluid room temperature phosphorescence properties of #alpha#-naphthyloxyacetic acid and #beta#-naphthyloxyacetic acid

摘要

In this paper, the non-protected room temperature phosphorescence (NP-RTP) properties of #alpha#-naphthyloxyacetic (#alpha#-NOA) and #beta#-naphthyloxyacetic acid (#beta#-NOA) and effects of organic solvents have been studied to clarify the effects of position of substituent on the luminescence. Both #alpha#-NOA and #beta#-NOA aqueous solutions can emit strong and stable RTP signal in the absence of a protecting medium by addition of KI or TINO_3 as heavy atom perturber (HAP) and Na_2SO_3 as deoxygenator. The fluid RTP system is completely transparent and stable. A good linearity between the RTP intensity and the concentration was obtained with detection limits of 1.0 * 10~(-8) and 1.2 * 10~(-8) mol/l, respectively, for #alpha#-NOA and #beta#-NOA. The kind and amount of organic solvent added to the luminescent system not only affect the RTP intensity and the pre-irradiation time requred to attain a stable RTP signal, but also the selection of HAP. Under the same conditions, the RTP intensity of the system using TINO_3 as HAP is much stronger than that of the system using KI a HAP, but the detection limits of both systems for analytical determination are comparable. The RTP intensity of #beta#-NOA is lower than that of #alpha#-NOA, but the influence of organic solvent on its RTP emission is also less. Determination of #alpha#-NOA in spiked pond water using standard additions method was performed, the recoveries are 97-102%.