(746b) Plasmonic Biosensors with Biocompatible Nanosilver
Noble metal nanoparticles and their unique plasmonic properties allow them to be used as agents for novel in-vivo bio-applications, such as targeted drug delivery and cancer cell therapy . Nanosilver is the optimum such material because of its lowest losses of the plasmonic properties in the visible spectrum. The toxic nanosilver surface , however, can destroy the surrounding healthy tissue and thus, challenges its safe employment . Therefore, “curing” nanosilver’s toxicity would open up its use for such innovative biological applications. Here, nanosilver particles are hermetically coated with a thin SiO2 layer using a scalable aerosol method . Uncoated or partially coated nanosilver exhibits substantial toxicity against E. coli bacteria, while encapsulating it prevents this. The performance of these ready-to-use, biocompatible nanosilver particles as biosensors is demonstrated by measuring the adsorption of bovine serum albumin (BSA) in a model sensing experiment. The silica coating prevents nanosilver agglomeration and thus, apart from the limited toxicity, enhances the biosensitivity.
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 Sotiriou, G. A., Sannomiya, T., Teleki, A., Krumeich, F., Vörös, J. & Pratsinis, S. E. Non-Toxic Dry-Coated Nanosilver for Plasmonic Biosensors. Adv. Funct. Mater. 20, 4250-4257 (2010).