Isolating Discrete Silver Nanoparticle-Single Stranded DNA Conjugates through Affinity Chromatography

Abstract

Noble Metal Nanoparticles are of huge interested because of their LSPR which gives rise to local field enhancement when two nanoparticles are in close proximity, also known as plasmon coupling.1The distance between the nanoparticles greatly affects this property and thus creating plasmonic structures that self-assembly in a repeatable and specific way is advantageous.1–3Thus methods to isolate discrete species are of huge interests, but until now it was difficult to isolate discrete plasmonic species with larger nanoparticles.4–6 Through the Yang Lab, an Affinity Chromatography (AC) method has been successful in isolating of discrete AuNP bioconjugates with diameters larger than 20nms.5 The focus of this project is to apply this method to silver nanoparticles (AgNP), which of huge interest since creating AgNPs self-assembled structures have proven to be difficult.7–10 In this process we have attempted to create 10nm AgNPs conjugates and 4-nm AgNPs conjugates. However, in both circumstances the conjugates either were not binding specifically, the ssDNA would fall off, or the conjugate conditions were two severe for AC isolation.