Design of an antenna effect Eu(iii)-based metal-organic framework for highly selective sensing of Fe3+

Highly selective sensing of Fe3+ is very important due to its great effect on biological systems. A novel ligand [1,1 ':4 ',1 '':4 '',1 ''':4 ''',1 ''''-quinquephenyl]-2,2 '',2 '''',5 ''-tetracarboxylic acid (H(4)qptca) was designed and successfully obtained for the first time via three steps in high total yields according to the absorption spectrum of Fe3+. The europium(iii)-based metal-organic framework derived from H(4)qptca, {[Eu(qptca)(1/2)(H(2)qptca)(1/2)(H2O)(2)]center dot DMF}(n) (referred to as SLX-1), was then synthesized and used as a water-stable and highly selective luminescent sensor for Fe3+ in aqueous solution with a comparable detection limit using Ln-MOF probes (6.45 mu M) through the antenna effect of SLX-1. Furthermore, the luminescence quenching mechanism was also proposed as a competitive absorption mechanism.