Cellulose Acetate-Based Plasmonic Crystals for Surface-Enhanced Raman and Fluorescence Spectroscopy.

In order to meet environmental concerns, there is an increasing demand for biodegradable and sustainable materials in many areas, including photonics. Cellulose and its derivatives are potentially eco-friendly alternatives to conventional plastics, because of their abundance and lower environmental impact. Here, we report the fabrication of plasmonic structures by molding cellulose acetate into submicrometric periodic lattices, using soft lithography. The fabricated platforms can be used for the enhancement of Raman and fluorescence signals of a range of analytes including a model immunoassay utilizing a streptavidin-conjugated dye, which is characterized by a 23-fold enhancement in fluorescence signal intensity, which shows the potential of the platform to be further used for the assay-based development of diagnostic tools.