Rigid, specific, and discrete gold nanoparticle/antibody conjugates.
A general method of rigid, specific labeling of proteins with gold clusters has been devised. The method relies on the conjugation of a glutathione monolayer-protected gold cluster (MPC) with a single chain Fv antibody fragment (scFv), mutated to present an exposed cysteine residue. Efficient formation of a gold-thiolate bond between the MPC and scFv depends on activation of the gold cluster by chemical oxidation. Once formed, the MPC-scFv conjugate is treated with a reductant to quench cluster reactivity. The procedure has been performed with an MPC with an average Au(71) core and an scFv directed against a tetrameric protein, the influenza neuraminidase. A complex of the MPC-scFv conjugate with the neuraminidase was isolated, and the presence of four gold clusters was verified by cryoelectron microscopy.
Department of Structural Biology, Stanford University School of Medicine, California 94305, USA.
Christopher J
CJ
Ackerson
Pablo D
PD
Jadzinsky
Grant J
GJ
Jensen
Roger D
RD
Kornberg
D002852:Chromatography, Ion Exchange; D003545:Cysteine / Q000737:chemistry; D005978:Glutathione / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D018796:Immunoconjugates / Q000737:chemistry* / Q000302:isolation & purification; D007128:Immunoglobulin Fragments / Q000737:chemistry*; D016297:Mutagenesis, Site-Directed; D049329:Nanostructures / Q000737:chemistry*; D009439:Neuraminidase / Q000737:chemistry; D010084:Oxidation-Reduction
D018796:Immunoconjugates; D007128:Immunoglobulin Fragments; D006046:Gold; D009439:Neuraminidase; D005978:Glutathione; D003545:Cysteine