Dark field (DF) optical detection of gold nanoparticles (GNPs) is a single-molecule method which can be used for sensitive and specific detection of nucleic acid strands such as DNA and RNA. This thesis describes the development of a novel biosensor based on scattering GNPs, from a theoretical idea on paper to a working sensor system which is sensitive for specific DNA detection in the femtomolar range. Furthermore, the modification chemistry and theoretical simulations are described to provide insight into the reported sensing method and experimental setup. The light scattering and absorption properties of GNPs can be utilised for the detection of DNA. Binding of molecules to the GNP influences the local refractive index. The increase in refractive index can be measured as a proportional red-shift of the GNP extinction maximum; therefore GNPs are suitable for use as nanoparticle chemical sensors. Utilizing this approach it is possible to detect DNA in naturally occurring quantities. In total, five different DNA detection assays were investigated.
|Award date||5 Sep 2012|
|Place of Publication||Enschede|
|Publication status||Published - 5 Sep 2012|