(26b) Specific Targeting Stealth Nanoparticles Coated with Ultra-Low Fouling Peptide

Nanoparticle-based biotechnology is relevant to many biomedical applications including drug delivery, diagnosis, and biosensing. A large obstacle to these applications is nonspecific protein adsorption, which can result in cellular uptake, nanoparticle aggregation, or an immune system response. Here we present an ultra-low fouling all -natural peptide coating based on the design principle of alternating positively and negatively charged residues. These mixed charge peptides exhibit high resistance to nonspecific protein adsorption. Furthermore, they can be extended with a functional peptide sequence to achieve specific targeting. Integrating the ultra-low fouling peptide sequence with a functional peptide sequence allows replacement of nonfouling synthetic materials and avoids the complex chemistries used in bioconjugation. These peptide-coated gold nanoparticles display stability in salt solution, protein solutions, and even undiluted human blood serum. Particles lacking specific targeting moieties possess stealth properties, whereas particles containing specific targeting moieties (RGD) are specifically uptaken by cells. This talk will discuss the assembly conditions, characterization, stability, and versatility of the peptide-based gold nanoparticle system.