Preliminary Assays towards Melanoma Cells Using Phototherapy with Gold-Based Nanomaterials

Supplementary Materials - The following are available online at https://www.mdpi.com/2079-4991/10/8/1536/s1, Video S1: Thermal activation of HAOA-coated GNPs.Cancer like melanoma is a complex disease, for which standard therapies have significant adverse side effects that in most cases are ineffective and highly unspecific. Thus, a new paradigm has come with the need of achieving alternative (less invasive) and effective therapies. In this work, biocompatible gold nanoparticles (GNPs) coated with hyaluronic acid and oleic acid were prepared and characterized in terms of size, morphology and cytotoxicity in the presence of Saccharomyces cerevisiae, and two cell lines, the keratinocytes (healthy skin cells, HaCat) and the melanoma cells (B16F10). Results showed that these GNPs absorb within the near-infrared region (750–1400 nm), in the optical therapeutic window (from 650 to 1300 nm), in contrast to other commercial gold nanoparticles, which enables light to penetrate into deep skin layers. A laser emitting in this region was applied and its effect also analyzed. The coated GNPs showed a spherical morphology with a mean size of 297 nm without cytotoxic effects towards yeast and tested cell lines. Nevertheless, after laser irradiation, a reduction of 20% in B16F10 cell line viability was observed. In summary, this work appears to be a promising strategy for the treatment of non-metastatic melanoma or other superficial tumors.This research was funded by Fundação para a Ciência e a Tecnologia (FCT) through the projects: UIDB/00645/2020, UID/DTP/04138/2019, PTDC/MED-QUI/31721/2017 as well as by the PhD fellowship SFRH/BD/148044/2019 (J.L.).