Authors: G.A. Sotiriou, C.O. Blattmann, S.E. Pratsinis
Affilation: ETH Zurich, Switzerland
Pages: 49 - 52
Keywords: Ag nanoparticles, fabrication, LSPR, biotin, streptavidin
Development of biosensors for medical applications is an on-going research field of great importance. In particular localized surface plasmon resonance (LSPR) biosensors show a high potential to detect analytes at low concentrations in biological fluids. The sensor’s basic build-up is a usually transparent substrate onto which plasmonic nanoparticles (e.g. silver and gold) are structured. State of the art synthesis techniques are based upon lithographic methods which allow for sophisticated and highly sensitive nanoparticle constellations. Sensors will only find an application outside of the research laboratories if their manufacturing is inexpensive, scalable and reproducible. These key points reveal themselves as the major drawbacks of lithographic synthesis methods. In this project a new synthesis method, utilizing flame-spray pyrolysis, a scalable nanoparticle synthesis method, was investigated. These manufacturing issues were of primary importance. Silver, showing greater sensing capabilities and reduced costs in comparison to the conventionally used gold, were the heart of these sensors. Co-oxidizing different support materials with the silver as well as silica coating the nanoparticles allowed for the tuning of the sensitivity. Flow cell studies with adsorption of bovine serum albumin as well as the well-studied biotin-streptavidin system, showed their effectiveness and potential nevertheless their quick and facile fabrication.