Substrate softness increases magnetic microdiscs-induced cytotoxicity, in Nanoscale Adv.

Magnetic nanoparticles hold great promises as tools for manipulating cells in vivo or altering cellular processes. But they face a challenge of toxicity due to the magnetic materials. We show here that assessing their cytotoxicity in vitro in cells grown on substrates that exhibit mechanical properties close to those of their tissue of origin provide information that differs from standard assays performed on plates with non-physiological stiffness. This suggests that the interaction of cells with magnetic particles is sensitive to the stiffness of cell environment and must be anticipated from the design stage.