Efficient Tb3+-to-Eu3+ energy transfer for colorimetric luminescence sensing

State-of-the-art Tb-to-Eu energy transfer (TEET) efficiency (> 90%) under ultralow Eu3+ proportion (< 6%) has been achieved in Eu/Tb bimetallic lanthanide coordination polymers (LnCPs). The yellow-light-emitting sample as sensor exhibits micromolar l-phenylalanine (l-Phe) in water and serum via obvious yellow-to-green lumino-metric behavior, meanwhile nanomolar-level detection limits are determined in terms of an updated Stern-Volmer equation with high selectivity and competitiveness. Excited-state inter-ligand photon transfer (ESILPT) greatly contributes to superior TEET property and outstanding luminometric behavior. This work opens a window for developing sensitive and stable visualization sensing, being of values on monitoring biochemical markers.

Automated summary

This study achieves high-efficiency Tb-to-Eu energy transfer (>90%) in Eu/Tb bimetallic lanthanide coordination polymers with ultralow Eu3+ proportion (<6%). As a sensor, the yellow-light-emitting material exhibits visible luminescence behavior for micromolar-level detection of L-phenylalanine in water and serum, with high selectivity and competitiveness determined by an updated Stern-Volmer equation. The excited-state inter-ligand photon transfer is found to greatly contribute to the superior energy transfer and luminometric behavior of the material.