CdTe quantum dots (QDs) capped with two relevant biological thiols, glutathione (GSH) or cysteine (Cys) were synthesized in aqueous solution using CdCl 2, K 2TeO 3 and NaBH 4 and their chemical, spectroscopic and biocompatibility properties were assessed. Synthesized nanoparticles (NPs) are 3-6 nm in diameter, with emission spectra between 480-580 nm depending on QDs size, and emission quantum yields between 0.35-0.65. The toxicity of thiol-capped CdTe NPs to different bacterial strains was determined. Increased biocompatibility for Cys-capped QDs was observed. In addition, QDs uptake by eukaryotic cells was evaluated by fluorescence microscopy. CdTe-GSH NPs were incorporated into MKN45 cells only in the presence of lipofectamine. On the other hand, although CdTe-Cys NPs were freely incorporated into these cells, the amount of incorporation as well as the number of fluorescent cells was lower than that observed with GSH-capped QDs. Finally, no significant changes in cell morphology as a consequence of GSH- or Cys-capped QDs incorporation were observed. Summarizing, our results indicate that the as-synthesized GSH- and Cys-capped QDs display differential spectroscopic properties and cellular interactions, being CdTe-Cys more biocompatible than CdTe-GSH NPs.
Áreas temáticas de ASJC Scopus
- Ciencia de los materiales (todo)