Cellular Response of Polyvalent Oligonucleotide-Gold Nanoparticle Conjugates

Nanoparticles are finding utility in myriad biotechnological applications, including gene regulation, intracellular imaging, and medical diagnostics. This chapter uses genome-wide expression profiling to study the biological response of HeLa cells to gold nanoparticles functionalized with nucleic acids. It finds that the biological response to gold nanoparticles stabilized by weakly bound surface ligands is significant, yet when these same nanoparticles are stably functionalized with covalently attached nucleic acids, the cell shows no measurable response. One nanomaterial that is particularly promising for therapeutic and diagnostic applications is the polyvalent oligonucleotide-gold nanoparticle. Consisting of a gold core densely functionalized with DNA or RNA surface ligands, this nanomaterial exhibits many surprising properties as a result of its high surface density. DNA was synthesized using an Expedite 8909 Nucleotide Synthesis System using solid-phase phosphoramidite chemistry.