Hybrid Spectroscopy Helps Elucidate Fine Cell Wall Structure

Traditional light-based microscopy cannot provide nanometre-scale details because of the diffraction limit.

The Science

A key obstacle to large-scale production of biofuels is the resistance of biomass to deconstruction into simple biomolecules that can be converted to the desired fuels. This so-called recalcitrance is being studied intensively at the cellular level. Non-destructive, simultaneous chemical and physical characterization of materials at the nanoscale is a highly sought-after capability for understanding the underlying mechanisms of this cell wall recalcitrance to deconstruction. However, a combination of physical limitations of existing nanoscale technologies has made achieving this goal challenging. To overcome these obstacles, researchers at the Department of Energy’s BioEnergy Science Center (BESC) have developed a hybrid approach for nanoscale material characterization based on nanomechanical force microscopy in conjunction with infrared photoacoustic spectroscopy. The researchers targeted the outstanding problem of spatially and spectrally resolving plant cell walls. Nanoscale characterization of plant cell walls and the effect of complex phenotype treatments on biomass are challenging but necessary in the search for sustainable and renewable bioenergy. The BESC scientists were able to reveal both the morphological and compositional substructures of the cell walls. They found that the measured biomolecular traits are in agreement with the lower-resolution chemical maps obtained with infrared and confocal Raman microspectroscopies of the same samples. These results should prove relevant in fields such as energy production and storage, as well as medical research, where morphological, chemical, and subsurface studies of nanocomposites, nanoparticle uptake by cells, and nanoscale quality control are in demand.

Principal Investigator

Ali Passian
Oak Ridge National Laboratory

BER Program Manager

Shing Kwok

U.S. Department of Energy, Biological and Environmental Research (SC-33)
Biological Systems Science Division
[email protected]

References

Tetard, L., A. Passian, R. H. Farahi, T. Thundat, and B. H. Davison. 2015 “Opto-Nanomechanical Spectroscopic Material Characterization,” Nature Nanotechnology, DOI: 10.1038/NNANO.2015.168.