Exactly Matching the FRET Energy of the Functionalized Upconversion Nanoprobe to Boost the Sensing Performance toward Perchlorate

The design and development of ultra-accurate probe is of great significance, but there is still a big challenge for chemical sensing in complex practical detection scenes. Here, a unique optical nanoprobe with high sensitivity and anti-interference capability toward perchlorate is designed by exactly matching the FRET energy of the functionalized ligand with the green emission of the UCNPs. Benefiting from the design of specific recognition sites and the intrinsic superiority of the FRET mechanism, the nanoprobe demonstrates an ultralow detection limit of 1.6 nM, rapid response within 4 s, and excellent anti-interference ability even in the presence of 22 potential interferents. The reliable detection performance in complicated real cases is further verified in recognizing trace perchlorate from interferents with various fluorescent emissions and colors existing simultaneously. The proposed design strategy of nanoprobe is expected to open up a brand new methodology for ultra-accurate sensing.