The preparation of MnO₂/BSA/CdTe quantum dots complex for ratiometric fluorescence/ T₁-weighted MRI detection of H₂O₂

Hydrogen peroxide, as the second messenger in cells, plays an essential regulatory role in cell proliferation, differentiation and migration. How to effectively identify H₂O₂ signals, and detect H₂O₂ in circulating tumor cells, are essential for the early diagnosis of tumors. Herein a fluorescence and T₁-weighted MR dual-mode imaging material, named MnBQ, has been successfully prepared and characterized. Based on the chemical redox reaction between MnBQ and H₂O₂, a fluorescence/T₁-weighted MRI dual-mode sensor has been developed for quantitative analysis of H₂O₂, of which the lowest limit detection obtained from fluorescence and MRI could reach 2.841 μmol/L and 43.85 μmol/L, respectively. This imaging sensor has dual advantages of high sensitivity and high spatial resolution, which could be a good candidate for monitoring of H₂O₂ in vivo.