Synthesis and characterisation of peptide-based materials

Nature is an important source of inspiration for the creation of innovative materials that meet the demands of today’s society. The formation of complex materials from simple components is often driven by self-assembly and occurs on a large scale in Nature. This allows the formation of a host of ordered systems such as the cell membrane, proteins and DNA. For decades scientists have been interested in mimicking these materials by using self-assembling molecules composed of naturally occurring building blocks such as amino acids, sugars, lipids and nucleic acids. Peptides are composed of amino acids and easily synthesised, thus they lend themselves well to the incorporation into novel materials. This research focused on the synthesis and characterisation two types of peptide-based materials. Firstly a series of peptide amphiphile were synthesised, each consisting of a short peptide coupled to a diacetylene containing fatty acid tail. The self-assembly behaviour of these fibres was investigated using a series of techniques, including FTIR. In addition to this we were able to align these fibres using a high magnetic field and subsequently encapsulate the aligned fibres in a biocompatible hydrogel matrix. The diacetylene functionality can be polymerised using UV-light and becomes a characteristic blue colour. The colour of the polydiacetylene is subject to change as a direct result of environmental changes and as such these polydiacetylene containing peptide amphiphile fibres were used as sensors for polymer growth and cell adhesion to the surface of the fibres. The second part of the work focused on a synthetic route toward the virus capsid of a bacteriophage. The advantage of using a completely synthetic approach is that the virus capsid can then be easily functionalised to suit a particular need