Impressive near-infrared brightness and singlet oxygen generation from strategic lanthanide–porphyrin double-decker complexes in aqueous solution

Abstract Although lanthanide double-decker complexes with hetero-macrocyclic ligands as functional luminescent and magnetic materials have promising properties, their inferior water solubility has negated their biomedical applications. Herein, four water-soluble homoleptic lanthanide ( Ln = Gd , Er , Yb and La ) sandwiches with diethylene-glycol-disubstituted porphyrins ( DD ) are reported, with their structures proven by both quantum chemical calculations and scanning tunneling microscopy. Our findings demonstrate that the near-infrared emission intensity and singlet oxygen ( 1 O 2 ) quantum yields of YbDD and GdDD in aqueous media are higher than those of the reported capped lanthanide monoporphyrinato analogues, YbN and GdN ; the brightness and luminescence lifetime in water of YbDD are greater than those of YbN . This work provides a new dimension for the future design and development of molecular theranostics-based water-soluble double-decker lanthanide bisporphyrinates.