Abstract:

Starting from pyridine-2,6-dicarboxylicacid(DPA),a series of novel pyridine-2,6-dicarboxylic acid derivatives were synthesized. In these compounds,4-(hydroxymethyl)pyridine-2,6-dicarboxylate(4-HMDPA) and 4-{［bis(carboxymethyl)amino］ methyl}pyridine-2,6-dicarboxylate(4-BMDPA) were used as multifunctional ligands to coordiate with Tb(Ⅲ) and Eu(Ⅲ) and their complexes were prepared. The fluorescence properties of the solid complexes and their solutions were investigated in detail. The results indicate that the weak election-withdrawing group 4-hydroxymethyl in 4-position of pyridine in 4-HMDPA could weaken the fluorescence intensity of the lanthanide complexes. The contradistinctive experimental results show that the fluorescence intensities of these complexes are related to pH value of the aqueous solution and the dipole moment of solvent molecule: in the neutral aqueous solution,the fluorescence intensities of these complexes were strongest,while the less the dipole moment was,the stronger the fluorescence intensity was. 4-BMDPA is the better sensitizer and may be used as time-resolved fluorommunoassay.

Key words: Pyridine-2,6-dicarboxylic acid; Fluorescence property; Lanthanide complex