A MnO-[Ru(dpp)]Cl system for colorimetric and fluorimetric dual-readout detection of HO.

Two-dimensional (2D) MnO nanosheets were synthesized by a template-free and one-step route, and the dye [Ru(dpp)]Cl was linked onto the MnO nanosheet surface electrostatic interaction. The formed MnO-[Ru(dpp)]Cl hybrid was used for a dual optical detection for HO, an important reactive oxygen species (ROS). Upon addition of HO, the reaction of MnO with HO results in the dissolution of MnO nanosheets and simultaneous generation of O. The fading of the solution and simultaneous fluorescence change of [Ru(dpp)]Cl, sensitive to O, enables colorimetric and fluorimetric dual-mode detection of HO. The dual-output assay in a single probe provides a good sensitivity with a detection limit of 0.18 μM HO. The dual-signal strategy can efficiently overcome the shortcoming of the single detection mode, and improve the detection accuracy by an additional correction of output signals from each other. Moreover, the successful determination of HO in the serum samples demonstrates the potential applicability of the MnO-[Ru(dpp)]Cl based probe in biosensing and bioanalysis.