Foliar application of Pluronic P85-grafted single-walled carbon nanotubes induces thylakoid membrane structural remodeling

Moderation and optimization of the photosynthetic function of higher plants by nanomaterials is under intensive investigation, but remain still far from practical utilization. We have previously demonstrated that foliar spraying of Pluronic P85-grafted single-walled carbon nanotubes (P85-SWCNT) affects the functionality and structural organization of the photosynthetic thylakoid membranes in pea plants. In the present work, we further study in more details the structural changes in the photosynthetic machinery induced by P85-SWCNT treatment. Evidences are provided that P85-SWCNT induces thylakoid membrane remodeling, namely—partial membrane unstacking, thermal stabilization of the major light-harvesting complex of photosystem II and its migration toward the stroma lamellae. The observed effects are most pronounced for the highest used concentration of 300 mg/L P85-SWCNT. Our results reveal that P85-SWCNT in concentrations below 300 mg/L is an interesting object for further investigation of the potential application of nanomaterials in plant science, e.g., as nanocarriers of beneficial substances reaching the photosynthetic apparatus.