Aqueous Synthesis of Tunable Highly Photoluminescent CdTe Quantum Dots Using Rongalite and Bioimaging Application

Rongalite is a cheap, strong and stable reducing agent with broad industrial applications. Herein we report novel method for the preparation of water-soluble and small-size CdTe quantum dots (QDs) using rongalite to produce Te2− species in reaction medium for the first time. The synthesized QDs were characterized with transmission electron microscopy, spectroscopy, and confocal laser scanning microscopy. The influence of parameters such as the pH value of the precursor solution and the molar ratio of Cd2+ to TGA and Cd2+ to Te2− on the quantum yields of CdTe QDs was systematically investigated. Under the optimal conditions at pH 11.6 and selecting thioglycolic acid as capping agent, the as-synthesized CdTe QDs possessed 66% quantum yield with narrow bandwidth of 24 nm. Moreover, methyl thiazolyl tetrazolium (MTT) assays were employed to evaluate the cytotoxicity of the as-prepared semiconductor nanocrystals on HeLa cell lines. Bioimaging studies showed that the as-synthesized QDs were quickly taken up by HeLa cells and did not have obvious damage to the cells within an incubation period of 24 h. The results show that Rongalite is a very promising agent for the synthesis of a variety of quantum dots and Rongalite-based QDs may find broad applications.

Rongalite, a stable, cheap and strong reducing agent with broad industrial applications, was exploited for synthesizing quantum dots for the first time. Quantum dots with high quantum yield up to 66% and narrow bandwidth down to 24 nm were obtained and employed for bioimaging study.Figure optionsDownload as PowerPoint slide