Preparation and Characterization of Water-soluble and Highly Fluorescent Biopolymer-conjugated CdS Quantum Dots

Water-soluble, highly fluorescent (FL) and very stable biopolymer-conjugated CdS quantum dots (QDs) were prepared via ligand exchange process of CdS-TG QDs with a biopolymer based ligand. The salep biosource polymer can attach to the surface of CdS QDs to yield quantum dots having great properties. To provide evidences for the occurrence of ligand exchange process, the prepared bioconjugate CdS nanocrystals were characterized by thermo gravimetric analysis (TGA), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR).