Figure 2.

Understanding and modeling nanoparticle-chloroplast interactions. (A) The lipid exchange envelope penetration (LEEP) model was developed on isolated plant chloroplasts. It predicts that highly charged nanoparticles localize within chloroplasts while more neutrally charged nanoparticles are unable to enter these organelles (Reprinted with permission from Wong et al., 2016). (B) Similarly, the LEEP model for isolated plant protoplasts that includes a plant cell membrane as a barrier, predicts that nanomaterial charge magnitude determines whether particles enter plant protoplasts or localize in the cytosol or chloroplasts (Reprinted with permission from Lew et al., 2018). (C) Systematic studies of foliar delivery of nanoparticles of various sizes and charges in planta indicated that there is a size limit for uptake in leaf cells in which highly positively charged nanoparticles were more efficiently delivered into these organelles (Reprinted with permission from Hu et al., 2020).