Raj Kumar Rajaram Baskaran, Alexander van Teijlingen, Tell Tuttle, « Automated Descriptors for High-Throughput Screening of Peptide Self-Assembly », Faraday Discussions, 2025, 13596640
Open Access publication available here
Abstract: We present five automated descriptors: Aggregate Detection Index (ADI); Sheet Formation Index (SFI); Vesicle Formation Index (VFI); Tube Formation Index (TFI); and Fiber Formation Index (FFI), that have been designed for analysing peptide self-assembly in molecular dynamics simulations. These descriptors, implemented as Python modules within a Conda environment, enhance analytical precision and enable the development of screening methods tailored to specific structural targets rather than general aggregation. Initially tested on the FF dipeptide, the descriptors were validated using a comprehensive dipeptide dataset. This approach facilitates the identification of promising self-assembling moieties with nanoscale properties directly linked to macroscale functions, such as hydrogel formation.
Lamisse H. El-Qarra, Niccolò Cosottini, Chayanan Tangsombun, David K. Smith, « Formulation and Release of Active Pharmaceutical Ingredients Using a Supramolecular Self-Healing Two-Component Gel », Chem. Eur. J. 2024, e202402530
Open Access publication available here
Abstract: A two-component low-molecular-weight gelator (LMWG) formed from a modified amino acid and an aldehyde was formulated with active pharmaceutical ingredients (APIs). Basic APIs (propranolol, atropine) can be mixed with the LMWG prior to gel assembly while acidic APIs (naproxen, rosuvastatin) inhibit assembly by disrupting the LMWG imine bond and were loaded by diffusion after gel assembly. For diffusion-loaded gels, the API in the liquid-like phase was rapidly released, with the remainder, interacting with gel fibres, retained in the gel. Rosuvastatin release was particularly low with Saturation Transfer Difference (STD) NMR indicating interactions between the aromatic ring and the self-assembled gel network. Propranolol also interacted with the gel via its aromatic unit, and its release led to gel erosion. Using agarose as a polymer gelator additive reinforced the gel, restricting erosion. In contrast, atropine was readily released over a period of hours – it is primarily in the liquid-like phase with STD NMR indicating no interactions with the gel network. The atropine-loaded gel retained its thixotropic properties. Overall, APIs must be carefully chosen to optimise formulation/release. Of the APIs investigated, atropine has most potential for further development. Atropine has applications in treating myopia, and our results suggest potential ophthalmic applications of supramolecular gels.
Florian Trummer, Oliver Lade, Otto Glatter, Thomas Sottmann, Cosima Stubenrauch, « Microemulsions supported by octyl monoglucoside and geraniol. 3. Microstructure & general pattern », Colloids and Surfaces A: Physicochemical and Engineering Aspects, Volume 676, Part A, 2023, 132133
Open Access publication available here
Abstract: This paper completes previous studies on the phase behaviour and microstructure of the quaternary microemulsion water – cyclohexane – n-octyl-β-D-glucoside (β-C8G1) – geraniol. The properties of this system are almost insensitive to temperature, while they can be tuned easily by adding an alcohol as co-surfactant. The addition of the alcohol changes the composition of the interfacial film, which, in turn, is the tuning parameter for the quaternary system. Studies of the phase behaviour together with SANS and NMR measurements allo drawing a quantitative picture of how the domain size ξ, the curvature H, and the interfacial tension σab depend on the composition of the interfacial film. The SANS data of both oil-inwater and water-in-oil droplet microemulsions recorded near the emulsification failure boundary were evaluated with the Generalised Indirect Fourier Transformation (GIFT), revealing a growth towards cylindrical structures when approaching the respective critical end point. We will show that the general behaviour of ternary and quaternary systems is equal if the appropriate tuning parameters are chosen. In addition, we will show that it is possible to apply the scaling description derived for temperature-dependent ternary systems to composition-dependent quaternary systems: plotting the reduced domain size, the reduced curvature and the reduced interfacial tension against the proper reduced tuning parameter, i.e, either the reduced temperature or the reduced interfacial composition, leads to one master curve for all systems.
David K. Smith, « Supramolecular gels – a panorama of low molecular-weight gelators from ancient origins to next-generation technologies », Soft Matter, 20, 2024, 10-70
Open Access publication available here
Abstract: Supramolecular gels, self-assembled from low-molecular-weight gelators (LMWGs), have a long history and a bright future. This review provides an overview of these materials, from their use in lubrication and personal care in the ancient world, through to next-generation technologies. In academic terms, colloid scientists in the 19th and early 20th centuries first understood such gels as being physically assembled as a result of weak interactions, combining a solid-like network having a degree of crystalline order with a highly mobile liquid-like phase. During the 20th century, industrial scientists began using these materials in new applications in the polymer, oil and food industries. The advent of supramolecular chemistry in the late 20th century, with its focus on non-covalent interactions and controlled self-assembly, saw the horizons for these materials shifted significantly beyond their historic rheological applications, expanding their potential. The ability to tune the LMWG chemical structure, manipulate hierarchical assembly, develop multi-component systems, and introduce new types of responsive and interactive behaviour, has been transformative. Furthermore, the dynamics of these materials are increasingly understood, creating metastable gels and transiently-fueled systems. New approaches to shaping and patterning gels are providing a unique opportunity for more sophisticated uses. These supramolecular advanced are increasingly underpinning and informing next-generation applications – from drug delivery and regenerative medicine to environmental remediation and sustainable energy. In summary, this article presents a panoramaover the field of supramolecular gels, emphasizing how both academic and industrial scientists are building on the past, and engaging new fundamental insights and innovative concepts to open up exciting horizons for their future use.