One-pot aqueous synthesis of gadolinium doped CdTe quantum dots with dual imaging modalities

A facile one-pot strategy has been developed for the aqueous synthesis of Gd doped CdTe (Gd:CdTe) QDs as fluorescence and magnetic resonance imaging dual-modal agent. The prepared Gd:CdTe QDs showed narrow size distribution and the average size was less than 5 nm. The amount of Gd³⁺ dopant in Gd:CdTe QDs significantly affected the optical properties of obtained QDs. The highest PL QY for the prepared Gd:CdTe QDs was up to 42.5%. The QDs showed the weak toxicity and significant enhancement in MRI signal. The specific relaxivity value (r1) was determined to be 4.22 mM^-1s^-1. These properties make the prepared Gd:CdTe QDs be an effective dual-modal imaging agent and have great potential applications in biomedical field.