title: Ethylene glycol monolayer protected nanoparticles for eliminating nonspecific binding with biological molecules.
abstract: The usefulness of the hybrid materials of nanoparticles and biological molecules in many occasions depends on how well one can achieve a rational design based on specific binding and programmable assembly. Nonspecific binding between nanoparticles and biomolecules is one of the major barriers for achieving its utilities in a biological system. In this paper, we demonstrate a new approach to eliminate nonspecific interactions between nanoparticles and proteins by synthesizing ethylene glycol protected gold nanoparticles. We discovered that with the water content optimized in the range of 9-18% in the reaction mixture, di-, tri-, and tetra(ethylene glycol) protected gold nanoparticles Au-S-EGn (n = 2, 3, and 4) could be directly synthesized. These gold nanoparticles that are bonded with a uniform monolayer with defined length varying from 0.8 to 1.6 nm (from molecular modeling) have great stability in aqueous solutions with a high concentration of electrolyte and organic solutions. Using ion-exchange chromatography and gel electrophoresis, we demonstrated that these Au-S-EGn (n = 2, 3, or 4) nanoparticles have complete resistance to protein nonspecific interactions. These types of nanoparticles provide a fundamental starting material for designing hybrid materials composed of metallic nanoparticles and biomolecules.
authors.affiliation: DuPont Central Research and Development, Experimental Station, Wilmington, Delaware 19880, USA.
authors.forename: Ming
authors.initials: M
authors.lastname: Zheng
authors.forename: Fredric
authors.initials: F
authors.lastname: Davidson
authors.forename: Xueying
authors.initials: X
authors.lastname: Huang
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry*; D003574:Cytochrome c Group / Q000737:chemistry; D005026:Ethylene Glycols / Q000138:chemical synthesis / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D009113:Muramidase / Q000737:chemistry; D009211:Myoglobin / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods; D010316:Particle Size; D011485:Protein Binding; D011506:Proteins / Q000737:chemistry*; D012259:Ribonuclease, Pancreatic / Q000737:chemistry; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D003574:Cytochrome c Group; D005026:Ethylene Glycols; D009211:Myoglobin; D011506:Proteins; D013438:Sulfhydryl Compounds; D006046:Gold; D012259:Ribonuclease, Pancreatic; D009113:Muramidase