Surface Ligand Induced Synthesis Of Low Cytotoxic Cadmiun Telluride Quantum Dots And The Morphology Revolution

CdTe quantum dots is a kind of high-performance, versatile nanomaterials. The good biocompatibility of CdTe quantum dots makes them have good applications in the field of cell images. However, not only CdTe quantum dots themselves, but also the surface ligand TGA are highly toxic materials, and they may have conspicuous influence on cell viability. Moreover, in order to conform with some special demands, for example photoelectric property, one-dimensional CdTe nanorods have appeal a lot of attention. Nevertheless, the synthesis conditions of CdTe nanorods are rigorous. Therefore, it is important to explore the novel method to overcome the cytotoxicity and the difficulties of synthesis. This paper is centered on these two questions. The main content of research is as follows:(1) We mixed the CdTe quantum dots and gold nanoparticles together, which made the complete ligand transformation of CdTe quantum dots from toxic TGA to green citrate. It was attributed to the Cd-S bond breaking and the Au-S bond formation. The new-born citrate capped CdTe quantum dots exhibited high stability in a wide pH range and high salt concentration. In comparison with the original TGA-capped quantum dots, the citrate capped CdTe quantum dots could induce minimal cytotoxicity against human hepatocellular liver carcinoma even at high dosages.(2) We developed a new way to synthesize one-dimensional CdTe nanorods. Compared with other synthetic methods, this kind of means would be more convenient and exercisable. The fluorescence property of the as-prepared CdTe nanorods was superior. The generation from dots to rods was attributed to the electronegative carboxyl of TGA, which would partially change to uncharged with the pH of colloid solution. Moreover, the growth mechanism of CdTe nanorods was oriented attachment, which was accorded with the thermodynamic principle.