Chemical and Biochemical Silica Surface Modifications for the Development of Medical Analyses
Thesis or dissertation
University of Exeter
This report can be divided into two parts. The first part studying the aggregation kinetics for citrate-reduced 15 nm gold nanoparticles at the native silica and modified silica-water interfaces. At the native, negatively charged silica-water interfaces a two-phase adsorption is observed: a pseudo-Langmurian adsorption phase and, after an acid wash to remove the citrate ligand from the adsorbed particles, a further pseudo-Langmurian adsorption phase. A kinetic analysis of these phases shows an average adsorption rate constant of (2.0 ± 2.5) 105 M 1 s 1 with no measurable desorption. The second part of this report describes protocol development for tethering DNA onto gold nanoparticles and the development of hybridization procedures. 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/N-Hydroxysuccinimide (EDC/NHS) activation of a thioctic acid monolayer on a gold nanoparticle shows the most promising method.
MPhil in Biological Sciences