Giuliano Zanchetta, featured ILCC liquid crystal artist, February 2011

Giuliano Zanchetta received his PhD in Physics in December 2007 from the University of Milano (advisor Tommaso Bellini) with a thesis on LC ordering of short DNA fragments, for which he was awarded the Glenn Brown Prize in 2008.

In 2008 he was a post-doctoral research associate at the University of Colorado at Boulder, in the Liquid Crystal Materials Research Center directed by Noel Clark, and he is currently a postdoc at the University of Milano, in the Complex Fluids and Molecular Biophysics Lab.

His research focuses on the experimental investigation of complex fluids and self-assembly of biomolecules, in particular the liquid crystalline ordering and phase separation in DNA and RNA aqueous solutions, interactions between liquid crystals and biomolecules, aggregation phenomena in colloids, polymers and proteins.
Aqueous solutions of short DNA helices were recently found to show chiral nematic and hexagonal columnar LC phases, although they are poorly anisotropic in shape. Such phases are produced by the end-to-end adhesion and consequent stacking of the duplex oligomers into long rod-shaped aggregates, which can order into liquid crystals (M.Nakata et al. Science 318, 1276 (2007)).

The picture reproduces the columnar liquid crystalline (LC) phase in a concentrated aqueous solution of small fragments of double-stranded DNA (20 nucleotides long self-complementary sequences: AACGCAAAGATCTTTGCGTT). The sample drop is surrounded by sealing oil (black).

The picture was taken in polarized transmitted optical microscopy on a TE200 Nikon Microscope, with a Nikon DS-5M camera. Image size is about 800 x 600 micrometers (10x objective). The sample is between two glass slides spaced by a 10 micrometers film.

Jury comment: What makes this plain columnar liquid crystal appear like a contorted and crinkled metal band with tempering colors? Unbelievable! Zanchetta is one of the masters of liquid crystal art!