A Terbium‐Organic Framework Material for Highly Sensitive Sensing of Fe³⁺ in Aqueous and Biological Systems: Experimental Studies and Theoretical Analysis

Abstract

Abstract Owing to the paramount importance of iron in biological and environmental systems, advanced agents towards the detection of iron ions with high sensitivity and selectivity have been targeted for decades.Here a new super water‐stable agent, namely terbium metal‐organic framework (Tb‐MOF), [H 2 N(CH 3 ) 2 ][Tb(cppa) 2 (H 2 ‐ O) 2 ],( CTGU‐1 , CTGU=China Three Gorges University, H 2 cppa=5‐(4‐carboxyphenyl)picolinic acid),has been successfully synthesized and demonstrated as a fluorescent turn‐off sensor for highly sensitive detection of Fe 3+ with the detection limit of 10 −9 M in dimethylformamide (DMF), 10 −7 M in water and 10 −7 M in biological environment,respectively. Such detecting capacity, to our knowledge, is the best compared to those of reported lanthanide‐baed MOF fluorescent probes so far. With the combination of first principle calculations, the detecting capacity has been analysed from the interaction between metal ions and organic ligands, particularly the effect of metal ions on the frontier molecular orbitals. This work offers a new Ln–MOF probe towards the detection of metal irons with high sensitivity and selectivity.