Biosynthesis of cadmium sulphide quantum dots by using Pleurotus ostreatus (Jacq.) P. Kumm

The development of green' technologies in nanoparticle synthesis is of considerable importance to broaden their biological applications. Cadmium sulphide nanoparticles are considered very promising in applied chemistry, bioscience and medicine. The aim of this study was to develop an efficient, easily reproducible and environmentally friendly method for biosynthesis of cadmium sulphide quantum dots based on the usage of mycelium of the basidiomycete fungus Pleurotus ostreatus. By incubating P. ostreatus mycelium with inorganic cadmium sulphate and sodium sulphide, we synthesized stable luminescent CdS nanocrystals. They showed absorption peaks at 453 nm (ultraviolet-visible spectrometry) and a main luminescent peak at 462 nm. Transmission electron microscopy revealed that the obtained quantum dots were of a spherical shape and predominantly from 4 to 5 nm in size. The electron diffraction pattern confirmed the wurtzite crystalline structure of the synthesized cadmium sulphide quantum dots. The obtained results confirm for the first time that the system based on basiodiomycete fungi could be considered promising for synthesizing semiconductor quantum dots.