Fractal Silver Dendrites as 3D SERS Platform for Highly Sensitive Detection of Biomolecules in Hydration Conditions

In this paper, we report on the realization of a highly sensitive and low cost 3Dsurface-enhanced Raman scattering (SERS) platform. The structural features of the Ag dendritenetwork that characterize the SERS material were exploited, attesting a remarked self-similarity andscale invariance over a broad range of length scales that are typical of fractal systems. Additionalstructural and optical investigations confirmed the purity of the metal network, which wascharacterized by low oxygen contamination and by broad optical resonances introduced by the fractalbehavior. The SERS performances of the 3D fractal Ag dendrites were tested for the detection oflysozyme as probe molecule, attesting an enhancement factor of ~2.4×106. Experimental resultsassessed the dendrite material as a suitable SERS detection platform for biomolecules investigationsin hydration conditions.