With its receptors expressed on brain capillary endothelial cells (Visser et al., 2004; Johnsen and Moos, 2016), NPs modified with transferrin (Tf) are being extensively studied for drug delivery as potential treatments for brain cancers and several neurodegenerative diseases (Wiley et al., 2013; Johnsen et al., 2019; Ullman et al., 2020). Here, TF is linked to brain cancer.