Seminars Archive
Biomolecular Self-Assembly for the Development of Advanced Biomaterials: A Multi-Technique Spectroscopic Approach
Department of Physics and Geology, University of Perugia
Abstract
Nanostructures formed through the self-assembly of biological molecules possess intriguing physicochemical properties, making them excellent candidates for developing new materials. Various strategies have been explored to induce the formation of ordered architectures and to control their structure and morphology. Among these, globular proteins, lipids, and peptides have drawn significant attention due to their capacity to form versatile supramolecular architectures. The first focus of this study is a multi-scale spectroscopic analysis of β-lactoglobulin (1) and albumin aggregation. This work combines molecular-level insights from FTIR and UVRR spectroscopy with nanoscale structural information obtained through SAXS. Molecular interactions are shown to influence both the size and morphology of the aggregates, as well as their macroscopic viscoelastic properties, measured using transient grating spectroscopy (2). A strong correlation between the macroscopic, mesoscopic, and molecular properties of β-lactoglobulin and albumin aggregation was revealed, providing valuable insights for improving the preparation of protein-based composite hydrogels with tunable viscoelasticity an essential characteristic in the food industry. The second system we studied is monolinolein lipid, which self-assembles in water to form lipid mesophases (3). We focused on the structural and molecular characterization of this system during its phase transitions from the double gyroid (Ia3d) to double diamond (Pn3m) cubic phases, and subsequently to the reverse hexagonal (HII) phase. By combining FTIR and SAXS techniques, we found that in the HII phase, a larger fraction of water is hydrogen-bonded to the lipid headgroups at higher temperatures compared to the cubic phase at lower temperatures. These lipid mesophases remain stable even in the presence of excess water (4), highlighting their potential as drug delivery systems. The third system we investigated is the short peptide diphenylalanine (FF), recognized as an excellent building block due to its ability to form well-ordered architectures with diverse morphologies. We explored how FF self-assembly properties can be modulated by adjusting the interactions between the aromatic side chains and their microenvironment, achieved by varying the acetonitrile/water ratio (5). Our findings revealed a hierarchical aggregation process, where the morphology can be precisely tuned by altering the AcN content. This strong morphological tunability makes FF a promising candidate for developing theranostic particles when chromophores are attached to the peptide scaffold.
1 Venturi, Sara, et al. "Amyloidogenic and non-amyloidogenic molten globule conformation of β-lactoglobulin in self-crowded regime." International Journal of Biological Macromolecules 242 (2023): 124621.
2 Catalini, Sara, et al. "Multi-length scale structural investigation of lysozyme self-assembly." Iscience 25.7 (2022).
3 Yao, Yang, et al. "Probing water state during lipidic mesophases phase transitions." Angewandte Chemie 133.48 (2021): 25478-25484.
4 Yao, Yang, et al. "Water–lipid interface in lipidic mesophases with excess water." Faraday Discussions 249 (2024): 469-484.
5 Catalini, Sara, et al. "Multiple length-scale control of Boc-protected diphenylalanine aggregates through solvent composition." Materials Advances 5.9 (2024): 3802-3811.
