The research fellow will dedicate entirely her/his activity to set up some elastic gels and macro-porous sponge/foams with the appropriate composition and viscoelastic properties able to selectively adsorb and detach the starch grains from the surface of hard porous materials such as stones, bones, tooth, without altering them allowing the subsequent release of them for the analysis typical of molecular archaeology. Starting from some well-known formulations (highly viscous polymeric dispersions composed by polyvinyl alcohol covalently crosslinked with borax and poly-dimethyl-siloxane macro-porous sponges/foams), these large interface systems will be adapted in terms of chemical composition and viscoelastic properties to reach the goal indicated above. The first part of the research activity will be articulated in two different steps: (i) formulation of some stable smart materials that succeed in interacting with starch grains without altering them, and (ii) physicochemical characterization and optimization of the systems set up with particular focus on their structure and dynamics that will be investigated by means of FTIR, SEM, micro-CT, SAXS, DSC, and rheology. The fellow’s research will continue with the application of the best materials to (i) some lab mockup simulating real samples, and (ii) to archaeological finds with the subsequent characterization of the biogenic residues extracted. The experimental conditions will be optimized in terms of water and/or solvent content, contact time, temperature, viscoelasticity of the materials, etc. The evaluation of the performances and the quality of the smart materials set up, besides the chemistry of the extracted biogenic residues, will be carried out by FTIR and UV-vis spectroscopy, microscopy, GC-MS, LC-MS. A comparison between the physicochemical characterization performed on the starch grains extracted by traditional methods and by the new smart materials will be provided.
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