Figure 2.

Schematic of the uptake and general toxicity mechanism of ion-releasing nanoparticles. NPs can enter cells by active internalization processes or endocytosis-free mechanisms. In case of uptake regulated by energy-dependent processes, NPs are rapidly confined in vesicular structures, endosomes, and finally in lysosomes. The acidic lysosomal pH triggers a lysosome-enhanced Trojan horse effect and enhanced release of the relatively toxic ions which subsequently results in elevated ROS levels, apoptosis, DNA and membrane damage. This figure has been reproduced with permission from Mir et al. [26] © 2020, Nature Publishing Group.