Targeted Carbon Nanostructures for Chemical and Gene Delivery to Plant Chloroplasts

ACS Nano. 2022 Aug 23;16(8):12156-12173. doi: 10.1021/acsnano.2c02714. Epub 2022 Aug 9.


Nanotechnology approaches for improving the delivery efficiency of chemicals and molecular cargoes in plants through plant biorecognition mechanisms remain relatively unexplored. We developed targeted carbon-based nanomaterials as tools for precise chemical delivery (carbon dots, CDs) and gene delivery platforms (single-walled carbon nanotubes, SWCNTs) to chloroplasts, key organelles involved in efforts to improve plant photosynthesis, assimilation of nutrients, and delivery of agrochemicals. A biorecognition approach of coating the nanomaterials with a rationally designed chloroplast targeting peptide improved the delivery of CDs with molecular baskets (TP-β-CD) for delivery of agrochemicals and of plasmid DNA coated SWCNT (TP-pATV1-SWCNT) from 47% to 70% and from 39% to 57% of chloroplasts in leaves, respectively. Plants treated with TP-β-CD (20 mg/L) and TP-pATV1-SWCNT (2 mg/L) had a low percentage of dead cells, 6% and 8%, respectively, similar to controls without nanoparticles, and no permanent cell and chloroplast membrane damage after 5 days of exposure. However, targeted nanomaterials transiently increased leaf H2O2 (0.3225 μmol gFW-1) above control plant levels (0.03441 μmol gFW-1) but within the normal range reported in land plants. The increase in leaf H2O2 levels was associated with oxidative damage in whole plant cell DNA, a transient effect on chloroplast DNA, and a decrease in leaf chlorophyll content (-17%) and carbon assimilation rates at saturation light levels (-32%) with no impact on photosystem II quantum yield. This work provides targeted delivery approaches for carbon-based nanomaterials mediated by biorecognition and a comprehensive understanding of their impact on plant cell and molecular biology for engineering safer and efficient agrochemical and biomolecule delivery tools.

Keywords: agrochemical delivery; chloroplast biotechnology; gene delivery; nanomaterial−plant interactions; peptides; smart agriculture.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Agrochemicals / analysis
  • Agrochemicals / metabolism
  • Agrochemicals / pharmacology
  • Chloroplasts / metabolism
  • Hydrogen Peroxide / metabolism
  • Nanostructures* / chemistry
  • Nanotubes, Carbon* / chemistry
  • Photosynthesis
  • Plant Leaves / chemistry
  • Plants


  • Nanotubes, Carbon
  • Hydrogen Peroxide
  • Agrochemicals