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Abstract: We report on the lyotropic phase behaviour of fully-hydrated mixtures of α-tocopherol (α-toc) with the unsaturated phospholipid dioleoyl phosphatidylcholine (DOPC), as studied by synchrotron small-angle x-ray diffraction. Increasing amounts of α-toc progressively swell the layer spacing of the fluid lamellar Lα phase of DOPC, and then induce a transition to an inverse hexagonal HII phase. Low-resolution electron density profiles show that this increase is largely due to an increased thickness of the bilayer, with little change in the water layer thickness. In the range 30 – 50 mol% α-toc, additional weak low-angle peaks were observed, whose characteristic ratios are in agreement with the presence of swollen inverse bicontinuous cubic phases of spacegroups Im3m / Pn3m. This research has applications both in the biological field and for industrial product development. We show that the effect of α-toc addition in DOPC membranes has some similarities to that of cholesterol by stabilizing inverse curvature structures, which play crucial roles in cell division, membrane trafficking and endocytosis. Concerning industrial applications, the stabilization of inverted hexagonal (HII) and swollen bicontinuous cubic phases offers the opportunity to develop new delivery systems.

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Abstract: Understanding the assembly of small molecules in aqueous media is crucial for the development of adaptive biomaterials. The mechanical properties of supramolecular networks, including stiffness and stress relaxation, play a key role in cellular spreading and can be tuned via formulation strategies or monomer design. Here, we demonstrate the modulation of supramolecular polymerization and cellular response of ureidopyrimidinone (UPy) monomers in water by tailoring the length of the alkyl spacer within the monomer structure. A library of four UPy derivatives with varying hydrophilic–hydrophobic balances was synthesized by using an optimized synthetic approach. The assembly behavior and dynamics of the supramolecular polymers were investigated both in solution and gel states using a wide range of techniques. The results revealed that the alkyl spacer length significantly affects the supramolecular polymer dynamics, kinetics, and stability. Monomers with 6 and 8 methylene units formed dynamic elongated structures, while those with 10 and 12 units yielded robust and stable bundled fibers. In the gel state, a physical cross-linker was required for gel formation. The gels formed by the monomers featuring 8 and 10 methylene units exhibited optimal mechanical properties, promoting the spreading of human normal dermal fibroblasts in both 2D and 3D cultures. These findings highlight the impact of the monomer architecture on the properties of UPy supramolecular systems, paving the way for the rational design of biomaterials with tunable properties.

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Abstract: Structural biomarkers determined by X-ray scattering of the tissues can complement conventional diagnostics and provide a pathway for early detection of diseases. In the present study, mouse models were utilized to observe the progression of prostate cancer. We induced cancer in the left lobe of the mouse prostate, whilst the right lobe was left uninoculated. The mice were sacrificed at increasing systematic time points, and lobe samples were subsequently analyzed using X-ray scattering. Control samples were also collected from healthy mice sacrificed at the same time points. This investigation revealed that the ratio between the X-ray scattering peaks associated with the lipids and water can serve as a structural biomarker of cancer, and this biomarker develops as the tumor advances. The obtained cancer trajectory can serve as a baseline for the determination of the disease stage, and the biomarker movement along the trajectory can be evidence of the healing or disease progression.

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Abstract: The mixing of Guanosine (Gua) and Guanosine 5′-monophosphate (GMP) in water in selected compositions yields highly hydrated, transparent, and self-healing self-assembled supramolecular G-hydrogels, attractive for biomedical applications. This work investigates how hydrogel composition affects solute transport, including diffusion, binding, loading, and release properties, using a set of fluorescent probes with varying size and polarity. Although small/wide-angle X-ray scattering techniques showed that no structural changes are induced by probe addition, even when intercalation into G-quadruplexes is expected, the internal mesh structure of the hydrogel, modulated by the Gua:GMP ratio, directly impacts probe diffusivity and loading. Tighter networks (e.g., 1:1) slow diffusion and enhance retention compared to looser configurations (e.g., 1:4). Moreover, UV–visible titrations revealed markedly different binding affinities (Kb ≈ 5.7 × 104 M–1 for DAPI, 8.0 × 103 M–1 for ThT, and 1.4 × 102 M–1 for RhB), which are expected to result in lower diffusion coefficients and slower release, especially for DAPI and ThT. Indeed, diffusion coefficients, obtained via fluorescence recovery after photobleaching and time-resolved fluorescence spectroscopy, reach 90, 20, and 60 μm2/s for FITC-dextran, ThT, and RhB, respectively. Probe release kinetics, modeled via Weibull fitting, indicated sustained release with characteristic times (τ) between 9.6 and 23.2 h and β ≈ 1 in 1× PBS, consistent with predominantly Fickian diffusion. Remarkably, switching to 10× PBS significantly accelerated release (τ reduced by ≈ 40–50%), suggesting that ionic strength and/or pH changes critically affect not only probe-hydrogel interactions but also the internal gel architecture, altering porosity, mesh size, and network tortuosity, thus enhancing molecular mobility. Overall, the G-hydrogel system offers a structurally tunable and composition-dependent platform capable of finely regulating molecular transport and release profiles, making it highly suitable for controlled drug delivery and adaptive biomaterial applications.

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Abstract: Benzophenone-based materials remain widely used as photoinitiators for ultraviolet light-induced free radical polymerizations. Traditionally, polymerization is spatially controlled using top-down techniques such as photomasks, which produce well-defined polymeric films. In contrast, we present an alternative method for controlling polymerization by employing supramolecular materials to localize the photoinitiator. This approach uses benzophenone-functionalized dipeptides that are specifically tuned to enable supramolecular gel noodle formation, which act as structural templates. We show that polymerization of acrylate monomers around the gel noodles can increase the Young’s modulus by up to 2 orders of magnitude and produce mechanically robust structures that can be handled. The self-assembly of the supramolecular photoinitiators is also explored using viscosity and SAXS measurements, providing an understanding of why only 4BPAcFF successfully forms gel noodles. Our method offers a simple yet effective technique for localizing polymerization, enabling fine-tuning of mechanical properties and the fabrication of intricate designs such as hollow-core structures.