Real-Time Subcellular Imaging of Plant Signaling Molecules and Bio-Coronas by Near-Infrared Nanosensors

Chemical imaging at high spatiotemporal resolution is crucial for advancing plant sciences and biotechnology. We demonstrate optical nanosensors for subcellular imaging of signaling molecules (H 2 O 2 ) and lipid corona formation in plant tissues at high spatial (<1 μm) and temporal resolution (1 s) in the tissue transparent near-infrared (nIR) window. Nanosensor fluorescence peak quenching (12–25%) over time revealed the rapid propagation (<30 s) of exogenous H 2 O 2 waves (100 μM) from plant mesophyll to stomata and pavement cells. Ca 2+ induced higher endogenous H 2 O 2 in mesophyll cells, whereas organelle electron transport chain disruptors and salt stress generated similar H 2 O 2 across all leaf cell types. Furthermore, the nanosensor quenching kinetics in photosynthetic mesophyll (0.018 s –1 ) and epidermal (0.004 s –1 ) cells enabled the detection of plant lipid corona formation…