title: Bioactivation and cell targeting of semiconductor CdSe/ZnS nanocrystals with phytochelatin-related peptides.
abstract: Synthetic phytochelatin-related peptides are used as an organic coat on the surface of colloidal CdSe/ZnS semiconductor nanocrystals synthesized from hydrophobic coordinating trioctyl phosphine oxide (TOPO) solvents. The peptides are designed to bind to the nanocrystals via a C-terminal adhesive domain. This adhesive domain, composed of multiple repeats of cysteines pairs flanked by hydrophobic 3-cyclohexylalanines, is followed by a flexible hydrophilic linker domain to which various bio-affinity tags can be attached. This surface coating chemistry results in small, buffer soluble, monodisperse peptide-coated nanoparticles with high colloidal stability and ensemble photophysical properties similar to those of TOPO-coated nanocrystals. Various peptide coatings are used to modulate the nanocrystal surface properties and to bioactivate the nanoparticles. CdSe/ZnS nanocrystals coated with biotinylated peptides efficiently bind to streptavidin and are specifically targeted to GPI-anchored avidin-CD14 chimeric proteins expressed on the membranes of live HeLa cells. This peptide coating surface chemistry provides a novel approach for the production of biocompatible photoluminescent nanocrystal probes.
authors.affiliation: Department of Chemistry & Biochemistry, University of California Los Angeles, Los Angeles, California 90095, USA. fpinaud@chem.ucla.edu
authors.forename: Fabien
authors.initials: F
authors.lastname: Pinaud
authors.forename: David
authors.initials: D
authors.lastname: King
authors.forename: Hsiao-Ping
authors.initials: HP
authors.lastname: Moore
authors.forename: Shimon
authors.initials: S
authors.lastname: Weiss
mesh_terms: D000268:Adhesiveness; D001672:Biocompatible Materials; D001710:Biotin; D002614:Chelating Agents / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005978:Glutathione; D006367:HeLa Cells; D006801:Humans; D008163:Luminescent Measurements; D008667:Metalloproteins / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D008854:Microscopy, Electron; D036103:Nanotechnology; D009943:Organophosphorus Compounds; D010316:Particle Size; D010455:Peptides / Q000737:chemistry*; D054811:Phytochelatins; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000737:chemistry; D012666:Semiconductors; D012995:Solubility; D012997:Solvents; D019809:Streptavidin / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D002614:Chelating Agents; D008667:Metalloproteins; D009943:Organophosphorus Compounds; D010455:Peptides; D011993:Recombinant Fusion Proteins; D012997:Solvents; D001710:Biotin; C044965:trioctyl phosphine oxide; D019809:Streptavidin; D054811:Phytochelatins; D005978:Glutathione