Using gadopentetic acid monomeglumine (GdPM) as precursor to provide simultaneously the carbon source and gadolinium (3+) source, gadolinium-doped carbon quantum dots (Gd3+/CQDs-MH) with uniformly small size were obtained at a mild condition by microwave hydrothermal method which can realize a molecular level mixing. When GdPM was pyrolyzed under 250℃ for 45 min, Gd3+/CQDs-MH with high quantum yield (QY) and longitudinal relaxation rate (r1) were obtained. The contradiction between quantum yield and the relaxation properties has been well balanced, which is very difficult to avoid using traditional heating method. The prepared Gd3+/CQDs-MH with an average diameter of about 1.0 nm show little cell toxicity and exhibit a high photoluminescence quantum yield of 11.0%, as well as a high r1 value of 4 545.3 mmol-1·L·s-1 ([Gd3+]=0.01 mmol·L-1) with the doping mass fraction of gadolinium (3+) of 16.9%. Therefore, the Gd3+/CQDs-MH show big possibility for application in magnetic resonance/fluorescence bimodal molecular imaging. © 2015, SCIENCE PRESS. All right reserved.
