Authors: D. Thompson, K. Faulds, W.E. Smith and D. Graham
Affilation: University of Strathclyde, United Kingdom
Pages: 271 - 274
Keywords: silver nanoparticles, DNA, SERRS
Modification of oligonucleotides with gold nanoparticles was first reported ten years ago and opened up several new avenues of research as they can be used as a novel nanostructured building material but the conjugate can also be used to colorimetrically detect low concentrations of a target oligonucleotide, differentiating between full complementarity and a single nucleotide polymorphism visually. However, almost all the research has been concerned with using gold with little work on other metal nanoparticles such as silver. This is due to the synthesis method making it difficult to attain repeatable size and optical characteristics. What work has been done utilises direct conjugate – conjugate hybridisation or hybridisation to a functionalised surface. A benefit of using silver nanoparticles is that they open the door to other detection techniques. With silver nanoparticles dye molecules can be complexed to the surface along with oligonucleotides, creating a dual – functionalised Raman – active DNA – silver nanoparticle conjugate. Here we report the first use of DNA – silver nanoparticle conjugates in a sandwich assay format with colorimetric oligonucleotide analysis used to differentiate a single nucleotide polymorphism and creation of a DNA – silver nanoparticle Raman Biosensor that uses surface enhanced resonance Raman scattering (SERRS) to identify single nucleotide polymorphisms.