A Clean Route for Preparation of CdTe Nanocrystals and Their Conjugation with Bacterium

Abstract

The thiol-capped CdTe nanocrystals were obtained by a clean chemical approach with hydrazine hydrate. In alkaline aqueous solution, hydrazine hydrate reduced commercial tellurium to be active reactant, and further reduced to negative bivalent telluride for the preparation of CdTe nanocrystals. The resulting CdTe nanocrystals were characterized by UV-Vis absorption spectra, photoluminescence spectra, X-ray diffraction, and high-resolution transmission electron microscopy. The synthesized CdTe nanocrystals were stable with relatively strong photoluminescence in neutral and close neutral range, and further combined with living Corynebacterium glutamicum without any post-preparative treatment. The conjugation samples were observed on laser confocal microscope, and the photoluminescence signals can only be detected at the positions of Corynebacterium glutamicum, which suggests that the CdTe nanocrystals have been combined with Corynebacterium glutamicum successfully.