CRACKLE - the pattern of minute surface cracks on paintworks - is an ageing phenomenon caused by the dehydration and polymerization of the paint surface. My PhD project CRACKLE will explore the role of water in degradation and explore the degree to which solvation shells structure the water. What happens when the water threshold begins to limit the number of water molecules around each residue?

In order to do this, I will target gelatin, widely used as glue and binder and one of the most commonly reported proteins in cultural heritage. Gelatin is the highly disordered version of the fibrous protein, type I collagen, found in abundance in connective tissues, skin and bone. Following the published structure of collagen, this gives me the opportunity to contrast the same protein sequence in both a crystalline and disordered state.

The project will thermally degrade (a) freeze-dried and (b) freeze-dried and rehydrated samples of collagen and gelatin, and (c) dissolved gelatin (the latter at pH 4, 7, & 10). Time series of thermally degraded samples will be analysed using LC-MS/MS. This data will be directly comparable with large datasets on degraded collagen and gelatin in archaeological and cultural heritage samples in the Palaeoproteomics group at SNM. The second element of the project is MD and QM simulations of (i) solvation of collagen intact and degraded gelatin (ii) hydrolysis of gelatin peptide bonds respectively.

The abundance of collagen, its longevity and widespread application as a biomaterial (for example by Industrial partner, Devro) means that the results will have resonance outside the narrow world of Cultural Heritage. CRACKLE combines together my skills in experimental and computational chemistry with my passion for the study of cultural heritage. My exposure to industry and leading computational groups, as well as heritage partners, will be an obvious advantage to enhance my career.