(691j) A Plant Nanobionic Approach to Enhance Solar Energy Conversion of Extracted Chloroplasts Using Spontaneously Assembled Nanoparticles

The interface between plant organelles and non-biological nanostructures has the potential to impart the former with new and enhanced functions, and unlike photosynthetic proteins, has been relatively unexplored for energy applications. This nanobionic approach can yield isolated chloroplasts – plant organelles responsible for converting CO₂ and solar energy to glucose – that are more stable to reactive oxygen species ex vivo, possess enhanced solar conversion efficiencies, are able to produce glucose, and allow real time information exchange via embedded nanosensors for free radicals. We show that cationic or anionic single walled carbon nanotubes (SWNT) have the ability to passively transport and irreversibly localize within the lipid envelope of extracted plant chloroplasts from Spinacia oleracea. This mechanism extends to poly (acrylic acid) nanoceria (PAA-NC) and their corresponding nanotube complexes (SWNT-NC). Concentration of superoxide can be suppressed 59% by assembling PAA-NC inside chloroplasts. SWNT-NC promote photoactivity 3.1 times above controls while PAA-NC extend glucose production from 0.5 to 88 hours. SWNT chloroplast complexes also allow fluorescent reporting of nitric oxide generation. Nanobionic engineering of extracted plant organelles may contribute to developing biomimetic light-harvesting materials with regenerative properties, enhanced efficiency and prolonged lifetimes.