Magneto-plasmonic Co@M (M = Au/Ag/Au-Ag) core-shell nanoparticles for biological imaging and therapeutics

In this paper, the optical properties of magnetic-plasmonic core-shell nanoparticles are studied using the Mie theory and DDA method. DDA results are compared with Mie theory results for spherical core-shell NPs as it gives the exact solution. It is observed that the position of LSPR peak in core-shell nanostructures is tuned by changing the cores and shell thickness in the core-shell spherical nanostructures and aspect ratio as well as shell thickness in spheroidal core-shell nanostructures. In addition, the yolk-shell nanostructures exhibit enhancement of LSPR peaks, bandwidth, and their corresponding intensities, as compared to spherical core-shell nanostructures. The calculated absorption spectra at lambda(max) are obtained in the wavelength range of 336-698 nm. This study opens up the new potential of appropriate core-shell nanostructures in bio-imaging, drug delivery, biomedicine, and therapeutic uses. (C) 2020 Elsevier Ltd. All rights reserved.