Tb^(3+)-xylenol orange complex-based colorimetric and luminometric dual-readout sensing platform for dipicolinic acid and metal ions

A dual-readout sensing platform based on two signal transduction channels can integrate the unique advantages of each sensing pattern,compensate for the deficiency in the adaptive capacity,and enable a more convincing performance in analytical applications.Here,we introduce a responsive molecule dye,xylenol orange(XO),to combine with lanthanide terbium ions(Tb^(3+)).The resultant Tb^(3+)-XO complex exhibited tunable optical properties and was used as a novel colorimetric and luminometric dual-readout sensing platform for assaying the anthrax biomarker,dipicolinic acid(DPA).In the presence of Tb^(3+),the XO solution underwent a color change from yellow to magenta;however,upon adding DPA,the color changed back to yellow immediately,accompanied by the characteristic luminescence emission of Tb^(3+).Considering the strong affinity between DPA/XO and metal ions,the proposed sensing platform was further employed for the determination and differentiation of certain metal ions using linear discriminant analysis.This convenient dual-readout sensing platform offers several notable features and significantly promotes the application and development of lanthanide-based materials.