| Zusammenfassung |
The aim of this proposal is to use two dimensional ordered structures created under ultra high vacuum (UHV) conditions as a template for crystal growth in solution. These highly ordered nanostructures will be used to exploit molecular recognition and select desired molecules from solution. For example chiral surfaces will be created in order to exact enantiomeric discrimination from a racemic mixture. This will be achieved by evaporating small biomolecules, either nucleic acid bases or chiral amino acids, onto a gold single crystal surface. Such a surface will have a high level of molecular order as indicated by surface crystallography. The UHV evaporation technique will afford a high degree of control with regards to surface coverage, periodicity and orientation that could not be achieved via liquid deposition. Due to the inert characteristics of gold it will be possible to take out these surfaces from the UHV chamber and insert them into solution. Monolayers of the nucleic acid bases will also be produced on gold and the molecular recognition/selectivity from a solution of mixed bases will be measured. It is also envisaged that such well ordered monolayers could act as templates for three dimensional crystal growth from solution. Thus epitaxy, molecular recognition and selectivity will be examined using electrochemical scanning tunnelling microscopy (STM), scanning tunnelling spectroscopy and atomic force microscopy. |
