Application of functional group modified substrate in room temperature phosphorescence, II—heavy atom‐chelated filter paper for selective determination of α‐naphthalene acetic acid

Heavy atom-chelated filter paper was synthesized and used as the substrate for room-temperature phosphorescence (RTP). The synthesis conditions for chelated paper were studied. The Pb-chelated filter paper could selectively induce the RTP of alpha-naphthalene acetic acid (alpha-NAA). The excitation and emission wavelengths of RTP of alpha-NAA were 300 nm and 521 nm, respectively. The concentration of alpha-NAA was linear with the RTP intensity in the range 2 x 10(-6)-6 x 10(-4) mol/L (correlation coefficient, 0.9999). The concentration detection limit was 1.35 x 10(-7) mol/L and the absolute detection limit was 0.25 ng/spot. The RSD (n = 10) was 1.7%. The method was applied to the analysis of water and vegetable samples with satisfactory results. Because the heavy atom was directly chelated onto the filter paper, the heavy-atom effect on the RTP of NAA was further increased and the analysis procedure was simple, fast and economical.