Revving up photosynthesis with nanotechnology – take that, greenhouse effect!

What happens when you insert single-walled carbon nanotubes into the leaves of Arabidopsis? The semiconducting nanotubes integrate themselves into the chloroplasts’ outer envelope and triple photosynthetic activity by enhancing electron transport.

So should we be making genetically modified plants containing carbon nanotubes? Well probably not – you have to believe that 3.5 billion years of evolution has optimised photosynthesis pretty well to achieve a nice balance. But that doen’t mean that this research is without applications, such as making living leaves that perform non-biological functions (for example, detecting pollutants or pesticides), or constructing artificial energy harvesting systems which don’t contribute to climate change.

Plant nanobionics approach to augment photosynthesis and biochemical sensing. (2014) Nature Materials 13, 400–408 doi:10.1038/nmat3890 [Subscription] Abstract: The interface between plant organelles and non-biological nanostructures has the potential to impart organelles with new and enhanced functions. Here, we show that single-walled carbon nanotubes (SWNTs) passively transport and irreversibly localize within the lipid envelope of extracted plant chloroplasts, promote over three times higher photosynthetic activity than that of controls, and enhance maximum electron transport rates. The SWNT–chloroplast assemblies also enable higher rates of leaf electron transport in vivo through a mechanism consistent with augmented photoabsorption. Concentrations of reactive oxygen species inside extracted chloroplasts are significantly suppressed by delivering poly(acrylic acid)–nanoceria or SWNT–nanoceria complexes. Moreover, we show that SWNTs enable near-infrared fluorescence monitoring of nitric oxide both ex vivo and in vivo, thus demonstrating that a plant can be augmented to function as a photonic chemical sensor. Nanobionics engineering of plant function may contribute to the development of biomimetic materials for light-harvesting and biochemical detection with regenerative properties and enhanced efficiency.

Bioinspired materials: Boosting plant biology. Nature Materials News & Views (2014) 13, 329–331 doi:10.1038/nmat3926 [Subscription]