Direct synthesis of high-quality water-soluble CdTe:Zn2+ quantum dots.

The synthesis of water-soluble and low-cytotoxicity quantum dots (QDs) in aqueous solution has received much attention recently. A one-step and convenient method has been developed for synthesis of water-soluble glutathione (GSH)-capped and Zn(2+)-doped CdTe QDs via a refluxing route. Because of the addition of Zn ions and the epitaxial growth of a CdS layer, the prepared QDs exhibit superior properties, including strong fluorescence, minimal cytotoxicity, and enhanced biocompatibility.

Toxicity evaluation of CdTe quantum dots with different size on Escherichia coli.

Quantum dots (QDs) have a great potential for applications in nanomedicine. However, a few studies showed that they also exhibited toxicity. We used Escherichia coli (E.

Study of the bioeffects of CdTe quantum dots on Escherichia coli cells.

Quantum dots (QDs) hold great potential for applications in nanomedicine, however, only a few studies investigate their toxic- and bio-effects. Using Escherichia coli (E. coli) cells as model, we found that CdTe QDs exhibited a dose-dependent inhibitory effect on cell growth by microcalorimetric technique and optical density (OD(600)).

Bovine serum albumin-directed synthesis of biocompatible CdSe quantum dots and bacteria labeling.

A simple method was developed for preparing CdSe quantum dots (QDs) using a common protein (bovine serum albumin (BSA)) to sequester QD precursors (Cd(2+)) in situ. Fluorescence (FL) and absorption spectra showed that the chelating time between BSA and Cd(2+), the molar ratio of BSA/Cd(2+), temperature, and pH are the crucial factors for the quality of QDs. The average QD particle size was estimated to be about 5 nm, determined by high-resolution transmission electron microscopy.

Conjugation and fluorescence quenching between bovine serum albumin and L-cysteine capped CdSe/CdS quantum dots.

Water-soluble, biological-compatible, and excellent fluorescent CdSe/CdS quantum dots (QDs) with L-cysteine as capping agent were synthesized in aqueous medium. Fluorescence (FL) spectra, absorption spectra, and transmission electron microscopy (TEM) were employed to investigate the quality of the products. The interactions between QDs and bovine serum albumin (BSA) were studied by absorption and FL titration experiments.

The damage of outer membrane of Escherichia coli in the presence of TiO2 combined with UV light.

The biological consequences of exposure to TiO2, UV light, and their combined effect were studied on the Escherichia coli (E. coli) cells. The damage of outer membrane was observed for the cells after treatment of TiO2 or UV light.

The envelope damage of Tetrahymena in the presence of TiO2 combined with UV light.

The biological consequences of exposure to TiO(2), UV light and their combined effects were studied on the cellular envelopes of Tetrahymena. For Tetrahymena cells treated with TiO(2) or UV light alone, the cell membrane shrunk while still maintaining the original elliptoid shape. Cells treated by TiO(2) under UV light irradiation experienced the most serious damage by peroxidation.