One Pot Generation of Blue and Red Carbon Dots in One Binary Solvent System for Dual Channel Detection of Cr and Pb Based on Ion Imprinted Fluorescence Polymers.

Blue and red dual channel dual emission carbon dots (DDCDs) were synthesized by a one-step hydrothermal method in water-formamide binary system using citric acid and ethylenediamine as precursors. Then, the as-prepared DDCDs were directly employed for preparation of ion imprinted fluorescence polymers without further separation. Since Cr can only quench the fluorescence of blue CDs, while Pb only quenches the fluorescence of red CDs, dual channel detection of Cr and Pb can be achieved simultaneously based on ion imprinted fluorescence polymers. Under optimized conditions, the quenching effect [( - )/] at 440 nm for the blue channel against the concentration of Cr was linear from 0.1 to 6.0 μM, while that for the red channel at 580 nm against the concentration of Pb was linear from 0.1 to 5.0 μM. The detection limits for Cr and Pb can reach 27 nM and 34 nM, respectively. Satisfied recoveries have also been obtained for detection of Cr and Pb in real water samples. The application of this dual channel detection method will greatly simplify the heavy metal ion detection process in complicated water environments.