This presentation was delivered during the EOS Annual Meeting 2021 (https://www.europeanoptics.org/events/eos/eosam2021.html). It overviews the realization, characterization, and application of bio-inspired gold nanoparticles, coated with a thin layer of wool-extracted keratin (Ker-AuNPs), designed to be utilized as a photo-thermal agent in cancer treatment.  In vitro experiments performed on a human glioblastoma cell line (i.e., U87-MG), using viability assays, confirm the biocompatibility of Ker-AuNPs and localized photo-thermal heating capabilities. In addition, the versatility of the photo-thermal properties of AuNPs is utilized in the fight against COVID-19 by realizing a personalized and reusable face mask with smart self-destruction of pathogens.