Localized surface plasmon resonance effects by naturally occurring Chinese yam particles

In this paper, localized surface plasmon resonance (LSPR) effects by naturally occurring Chinese yam particles are observed and quantified. Chinese yam particles were found by atomic force microscope and high-speed optical dark-field microscope. The particles with diameters greater than 200 nm are found to contribute most of ultraviolet and visible absorption. LSPR effects of silver nanoparticles by the Chinese yam particles lead to the redshifts in the extinction peaks of the silver nanoparticles. The wavelength shifts are quantitatively predicted based on discrete dipole approximation of the LSPR effects, which are sensitive to the local dielectric constant changed by the Chinese yam particles. The finding may open a new avenue to detect the biological submicron particles or virus in solution.