 This study examined the effectiveness of a new polymeric hydrogel formulation containing nitric oxide donors and copper oxide nanoparticles against melanoma cells. The hydrogel was shown to reduce cell viability and increase levels of reactive oxygen species which led to cell death through nuclear damage, loss of mitochondrial membrane potential, and lipid peroxidation. These results suggest that the hydrogel could potentially be used as a therapeutic agent for treating skin cancer. This article was authored by Fernanda V. Cabral, Bianca de Mello Santana, Camila N. Lang, and others.