DNA Encountering Terbium(III): A Smart “Chemical Nose/Tongue” for Large-Scale Time-Gated Luminescent and Lifetime-Based Sensing

摘要

Recent years have witnessed the rapid development of pattern-based sensors due to their potential to detect and differentiate a wealth of analytes with only few probes. However, no one has found or used the combination of DNA and terbium(III) (Tb) as a pattern recognition system for large-scale mix-and-measure assays. Here we report for the first time that DNA-sensitized Tb (DNA/Tb), as a label-free and versatile “chemical nose/tongue”, can be employed for wide-scale time-gated luminescent (TGL) monitoring of metal ions covering nearly the entire periodic table in a cost-effective fashion. A series of guanine/thymine (G/T)-rich DNA ligands was screened to sensitize the luminescence of Tb (referring to the antenna effect) as smart pattern responders to metal ions in solution, and metal ion–DNA interactions can differentially alter the antenna effect of DNA toward Tb as pattern signals. Our results show that as few as 3 DNA/Tb label-free sensors could successfully discriminate 49 analytes, including alkali-metal ions, alkaline-earth-metal ions, transition/post-transition metal ions, and lanthanide ions. A blind test with 49 metals further confirmed the discriminating power of DNA/Tb sensors. Moreover, the lifetime-based pattern recognition application using DNA/Tb sensors was also demonstrated. This DNA/Tb pattern recognition strategy could be extended to construct a series of “chemical noses/tongues” for monitoring various biochemical species by using different responsive DNA ligands, thus promising a versatile and powerful tool for a sensing application and investigation of DNA-involving molecular interactions.