Chiral Nanomaterials

One of the rapidly expanding fields of inorganic materials is chiral inorganic nanostructures.  This interest to this type of biomimetic nanostructures was spurred by unusually strong circular dichroism (CD) observed for individual nanoparticles and their assemblies due to strong light-matter interactions with chiral plasmonic and excitonic states of nanoscale metals and semiconductors.  Since that time, significance of chiral nanomaterials to some of the new and old problems of chemistry, physics, biology, mathematics, and potentially to astronomy, exemplified by spintronics, chiral catalysis, and origin of Earrh’s homochirality, became also clear.   

We are working both on experiment and theory of chiral nanostructures with emphasis on understanding the biomimetic geometries and functions of chiral nanostructures.  Besides the well-established chirality transfer from bioorganic molecules extensively used in organic chemistry, other methods to impart handedness to nanoscale matter are being utilized.  They include multiphoton chirality transfer, and polarization effects in nanoscale assemblies, and others macro-to-nano chirality transfer via mechanical deformations.  Multiple chiral geometries were observed with characteristic scales from Ångströms to microns.

Currently we are working on the following questions in this field.

What are the differences and similarities with chiral structures known from biology and biochemistry?

How the chirality of individual nanoparticles at Ångström- and nano scale is being transferred through the scales to meso-, micro,- and macro inorganic structures?

Plasmonic inorganic nanostructures reveal particularly intense CD bands that exceed those for similarly sized organic and biological matter by at least an order of the magnitude. The chiroplasmonic nanoscale assemblies from gold nanoparticles and enabled high sensitivity of DNA/protein/peptides detection at single molecular levels.   Besides biosensors other practical implementations of chiral nanostructures being developed in this group include cancer therapy, chiral catalysis, and chiral photonics.