PEG molecular weight effect on stabilization of quantum dots in aqueous dispersions
발표자
()
초록
내용
Polyethylene glycol (PEG) ligands are widely used for stabilization of biologically functional nanoparticles (NPs). The major factors for choosing right PEG ligands are the chemical stability of the PEG anchors to the NP surface and the effective blocking of the PEG brushes against the proteins (so-called stealth effect). We address these issues by using di-thiol end-functionalization and varying the molecular weight of the PEG ligands with the model CdSe@Cd0.5Se0.5Zn quantum dots (QDs). The molecular weight is expected to affect the colloidal stabilization and prevention of the protein adsorption through changing the maximum grafting density and the thickness of the PEG brush. After substituting the native ligand with the synthesized di-thiol PEGs, QDs are transferred to aqueous phase and then challenged by acid/base, salinity, and albumin as a model plasma protein. The hydrodynamic diameter and spectroscopic results are used to assess the stabilizing capabilities of the PEGs.