Cell toxicity and preparation of streptavidin-modified iron nanoparticles and glutathione-modified cadmium-based quantum dots

Abstract

This paper is focused on the investigation of conjugate nanostructures consisting of superparamagnetic γ-Fe2O3 nanoparticles (NPs) and CdSe/CdS quantum dots (QDs) with core/shell structure. In the first step, we prepared streptavidin (STP) conjugated Fe2O3 magnetic particles. The next stage was preparation of QDs using method based on surface modification of hydrophobic core/shell CdSe/CdS with biotinylated glutathione. Glutathione (GSH) belongs to the most abundant peptides in organisms maintaining redox status, which, from the “particle” point of view, makes the QDs water-soluble and stabilized in aqueous solution. Biotin molecule is known for its excellent affinity to streptavidin and hence allows the conjugation of both nanostructures (magnetic and light-emitting). We tested the influence of both prepared nanostructures on growth and viability of fibroblasts and BY-2 tobacco cells, respectively. NPs-STP and QDs-GSH may not pose a threat to cells, but non-modified nanoparticles and QDs without GSH had a very adverse effect on cells.