The marvel of supermolecules which trap solvent and active ingredients
Liquid crystals change in response to temperature or electrical fields enabling their use in LCDs.
Dr Victor Chechik, Professor John Goodby, Dr Kathryn Harkup, Dr Isabel Saez, Dr David Smith and Professor Paul Walton.
University of York.
Tiny molecules with limited practical use often exhibit extraordinarily useful properties when they group together to form 'supermolecules'. A good example is the liquid crystal displays (LCDs) found everywhere from watches to mobile phones. 'Liquid crystals form spontaneously from small molecules and have the extremely useful property of changing orientation in response to temperature or electrical fields, enabling their use for visual display', explains John Goodby, of the Department of Chemistry at the University of York.
John and colleagues in three other research groups at York use a variety of approaches to manipulate molecules to generate nanoscale (one-billionth of ametre) structures with interesting applications. 'These nanoscale supermolecules are underpinned by fundamental chemistry, and show how engineering on a molecular level can give rise to real effects and properties on the macroscopic scale of the real world', says David Smith who works on nanoscale structures known as dendrimers.
Dendrimers are branching molecular structures which are able to spontaneously combine with DNA. The combined DNA dendrimer complex is then able to cross cell walls something that DNA can't do on its own. David and his colleagues are hoping that these structures could deliver DNA into cancer cells. Once in the cell, the DNA will encode for proteins that would destroy the cancer cell. David's research is also looking at ways of putting targets onto the DNA-dendrimer complexes so they enter only cancer cells rather than healthy cells. Dendrimers that self- assemble into gels with useful properties are being explored for use in pharmaceuticals and cosmetics. 'Imagine a gel which breaks down on rubbing into warm skin, to deliver its active ingredients into the body', says David.