The quinoline derivative of ratiometric and sensitive fluorescent zinc probe based on deprotonation

A new quinoline derivative probe (QZn1) with DPA as recognition group was designed and prepared for selective detection of Zn²⁺ in aqueous solution. The recognizing affinity is based on the selective deprotonation and coordination. The resulting fluorescence λem via ICT is at 499 nm, while the original fluorescence is at 407 nm. The fluorescence ratio (F₄₉₉/F₄₀₇) shows high selectivity and sensitivity (nanomolar level) to Zn²⁺ in aqueous solutions. QZn1 has ideal chemical and spectroscopic properties that satisfy the criteria for further biological and environmental applications.