B21-High Throughput SAXS
|
Bridget
Tang
,
Philip
Kitchen
,
Luke M.
Broadbent
,
Steven D.
Quinn
,
Nawal
Hassan
,
Siriporn
Chaimueangchuen
,
Barbara
Gerbelli
,
Katsuaki
Inoue
,
Nathan
Cowieson
,
Fátima
Herranz-Trillo
,
Alice J.
Rothnie
,
Roslyn M.
Bill
,
Paul D.
Topham
,
Alan D.
Goddard
,
Jacob J. K.
Kirkensgaard
,
Matthew J.
Derry
,
Andreas Haahr
Larsen
Diamond Proposal Number(s):
[39511]
Open Access
Abstract: Amphiphilic copolymers have emerged as powerful, detergent-free tools for solubilizing biological membranes, enabling the extraction and stabilization of membrane proteins within native-like lipid environments. We report a comprehensive, multi-technique elucidation of how polymer:lipid stoichiometry governs the formation, size, and stability of styrene-maleic acid lipid particles (SMALPs). Using commercial SMA2000, a styrene-maleic acid copolymer made using free radical polymerization and 1,2-ditetradecanoyl-sn-glycero-3-phosphocholine (DMPC) as a model phospholipid, we prepared SMALPs across a wide range of polymer-to-lipid weight ratios and employed an integrated suite of orthogonal characterization methods, including size exclusion chromatography (SEC), dynamic light scattering (DLS), flow-induced dispersion analysis (FIDA), mass photometry, ensemble and time-resolved Förster resonance energy transfer (FRET), and small-angle X-ray scattering (SAXS), to establish the structural consequences of varying polymer content. Our data reveal that efficient lipid solubilization into nanodiscs requires a minimum amount of polymer. Above ~1% (w/v) SMA2000: 1% DMPC, well-defined nanodiscs of ~10 nm diameter are formed that, on average, exhibit a consistent stoichiometry of ~130 lipids encircled by ~11 polymer chains. Through a new molecularly-constrained SAXS model, we show that these nanodiscs possess a stable bilayer height across variations in polymer to lipid ratio and a narrow polymer belt, and that their structural parameters remain invariant once excess polymer is used. In contrast, insufficient polymer (<1% w/v) generates bimodal populations including substantially larger discs. Notably, nanodiscs formed at optimal polymer:lipid ratios remain structurally stable for at least two months. Together, these results provide a rigorous quantification of SMALP composition and preferred size, enhancing our understanding of polymer-lipid nanodisc formation and offering critical design rules for detergent-free membrane protein extraction.
|
Jul 2026
|
|
labSAXS-Offline SAXS and Sample Environment Development
|
Diamond Proposal Number(s):
[34017, 37151, 39136]
Open Access
Abstract: Alpha olefin sulfonate (AOS) is a widely used anionic surfactant, yet its phase behaviour has not previously been systematically mapped. Here, a comprehensive phase diagram is constructed over a concentration range of 2–70 wt% and temperatures from 25 to 80 °C using cross-polarized optical microscopy and small-angle X-ray scattering (SAXS). Polarized microscopy was used to delineate isotropic and anisotropic regions and identify phase boundaries, while SAXS provided quantitative structural characterisation, including lattice parameters, electron density reconstructions, and micellar size and shape analysis. Measurements were performed in sealed capillaries under controlled thermal conditions, with refined temperature increments used to resolve phase transitions. Five distinct phases were identified with decreasing water content: a micellar dispersion; a 2D hexagonal phase; a 2D ribbon phase; a previously unreported 3D hexagonal phase; and two lamellar phases. This temperature- and concentration-dependent sequence is structurally analogous to that of sodium dodecyl sulfate (SDS), though key distinctions arise from the molecular architecture of AOS, which promotes unique intermediate mesophases through differences in molecular packing and constrained hydration. Structural analysis reveals a systematic evolution of spatial water organisation, progressing from excess bulk water in the micellar phase, to tubular confinement within hexagonal and ribbon phases, to discrete water pockets embedded within surfactant bilayers in the 3D hexagonal phase, and finally to residual interfacial hydration in the lamellar phases. This work establishes the relationship between hydration state and mesophase structure, and provides the first complete structural phase diagram for this important surfactant system, enabling prediction of phase behaviour under the complex conditions encountered in industrial processing.
|
Jun 2026
|
|
I22-Small angle scattering & Diffraction
|
Diamond Proposal Number(s):
[33748, 35376, 35348]
Open Access
Abstract: Pulsed potential (PP) electrodeposition was utilized for the first time to fabricate three-dimensional (3D) platinum (Pt) nanostructures within phytantriol-based double diamond cubic templates, both with or without 20 % w/w Brij-56 as a pore swelling agent. Unlike conventional direct potential (DP) deposition, the PP approach yielded Pt nanostructures with markedly enhanced uniformity and superior lattice ordering. Small Angle X-ray Scattering (SAXS) revealed that PP-grown structures exhibited sharp, well-defined Bragg peaks corresponding to lattice parameters of 134.2 ± 2.1 Å without Brij-56 and 236.7 ± 2.5 Å with 20 % w/w Brij-56, whereas DP-grown structures showed broader, less distinct peaks with smaller lattice parameter (130.7 ± 1.9 Å and 197.1 ± 2.8 Å, respectively). Notably, In-situ SAXS measurements provided real-time insights into the evolution of 3D Pt nanostructures, enabling direct monitoring of orientational and lateral ordering within the templated phases. High resolution SEM further confirmed the superior quality of PP-grown structures, revealing highly ordered 3D nanowire network with uniform pore sizes of 89.5 ± 1.3 (without Brij-56) and 102.0 ± 0.7 Å (with 20 % w/w Brij-56). Overall, these findings highlight the effectiveness of PP electrodeposition in mitigating structural inhomogeneities, establishing it as a powerful strategy for fabricating well-ordered 3D Pt nanostructures.
|
Nov 2025
|
|
B21-High Throughput SAXS
|
Diamond Proposal Number(s):
[31378]
Open Access
Abstract: Amphiphilic compounds, such as phospholipids or surface-active substances, are present in biological systems and can be part of pharmaceutical formulations. As a consequence, all pharmaceutically active ingredients will encounter amphiphilic compounds, either in the formulation or after administration. With the growing interest in peptide-based pharmaceuticals, there is a need to enhance the understanding of the interactions between peptides and amphiphilic compounds.
In this particular study, we have chosen to study mixtures of the comparatively small cyclical octapeptide lanreotide and the conventional anionic surfactant sodium dodecylsulfate (SDS). This was done by examining the self-assembly structures formed in lanreotide-SDS mixtures using light scattering and small-angle X-ray scattering (SAXS).
Above the critical micelle concentration (cmc) of SDS, the large excess of SDS could solubilize all lanreotide and form small micelles with lanreotide attached to the interface. Upon dilution to concentrations below the cmc of SDS, a suspension with dispersed solid nanoparticles is formed. The solid nanoparticles grow in size with decreasing concentration and, eventually, precipitate. The precipitated material is arranged in a liquid crystalline micellar phase, consisting of small close-packed SDS micelles with peptide adsorbed at the interface.
We were able to conclude that lanreotide does not form mixed micelles with SDS, indicating that it lacks the amphiphilic properties required to integrate fully with SDS behaving as a cosurfactant. In contrast, lanreotide attaches to the interface of SDS micelles, resembling the interactions of polymers, proteins, and nucleic acids with surfactants.
|
Nov 2025
|
|
B18-Core EXAFS
|
Diamond Proposal Number(s):
[36104]
Abstract: Seawater splitting has been considered an environmentally friendly and cost-effective method for hydrogen production. However, developing efficient electrocatalysts capable of enduring the severe corrosive conditions of natural seawaters for extended durations remains a notable technical challenge. Herein, the Ni3S2 supported NiFe oxalate ((NiFe)C2O4/Ni3S2) nanorod arrays were synthesised through hydrothermal and impregnation precipitation methods. Structural and spectroscopic analyses revealed that the (NiFe)C2O4/Ni3S2 catalyst formed an integrated oxide-sulfide interface with coexisting Ni–O/Ni–S coordination. This dual coordination environment, coupled with the presence of Fe in a higher oxidation state, confirmed interfacial electronic reorganization characterized by directional electron transfer from Ni to Fe. The resulting charge transfer pathway enhanced the electron delocalisation between active centers, thereby improving active site utilization. The obtained (NiFe)C2O4/Ni3S2 demonstrated remarkable catalytic activity for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in a simulated alkaline seawater solution (NaCl + KOH), with overpotentials of 363 mV (HER) and 295 mV (OER) at a current density of 500 mA cm−2 for industrial electrolysis requirements and remarkable stability over 100 h of durability testing. Additionally, the (NiFe)C2O4/Ni3S2 electrode pairs only required a cell voltage of 1.81 V to achieve 100 mA cm−2 with Faradaic efficiency of 98 % in 1.0 M KOH + seawater. This study presents a novel approach for fabricating multifunctional electrocatalysts, providing a promising pathway for advancing seawater electrolysis and supporting the development of cost-effective green hydrogen production technologies.
|
Nov 2025
|
|
I12-JEEP: Joint Engineering, Environmental and Processing
|
Diamond Proposal Number(s):
[26730]
Open Access
Abstract: Hydrogen (H2) storage in porous geological formations offers a promising means to balance supply and demand in the renewable energy sector, supporting the energy transition. Important unknowns to this technology include the H2 fluid flow dynamics through the porous medium which affect H2 injectivity and recovery. We used time-resolved X-ray computed microtomography to image real-time unsteady and steady state injections of H2 and brine (2 M KI) into a Clashach sandstone core at 5 MPa and ambient temperature. In steady state injections, H2 entered the brine-saturated rock within seconds, dispersing over several discrete pores. Over time, some H2 ganglia connected, disconnected and then reconnected from each other (intermittent flow), indicating that the current presumption of a constant connected flow pathway during multiphase fluid flow is an oversimplification. Pressure oscillations at the sample outlet were characterized as red noise, supporting observations of intermittent pore-filling. At higher H2 fractional flow the H2 saturation in the pore space increased from 20-22 % to 28 %. Average Euler characteristics were generally positive over time at all H2 flow fractions, indicating poorly connected H2 clusters and little control of connectivity on the H2 saturation. In unsteady state injections, H2 displaced brine in sudden pore-filling events termed Haines jumps, which are key to understanding fluid dynamics in porous media. Our results suggest a lower H2 storage capacity in sandstone aquifers with higher injection-induced hydrodynamic flow and suggest a low H2 recovery. For more accurate predictions of H2 storage potential and recovery, geological models should incorporate energy-dissipating processes such as Haines jumps.
|
Apr 2025
|
|
B21-High Throughput SAXS
|
Diamond Proposal Number(s):
[28659]
Abstract: In this research, we studied two novel lipopeptide sequences containing the amino acid serine (SPRWG) with one (compound 1) or two aliphatic tails (compound 2) to optimize the detection capabilities for organophosphate pesticides, specifically glyphosate. The study comprehensively explored how the incorporation of serine influences the physicochemical properties and supramolecular assembly of the lipopeptides, leading to enhanced interactions with glyphosate. Advanced analytical methods were employed to investigate these modifications, including fluorescence spectroscopy, circular dichroism, and small-angle X-ray scattering (SAXS). The results showed that serine significantly reduces the critical aggregation concentration, increases the hydrophilicity of the lipopeptides, and promotes the formation of distinct secondary structures—-turns in compound 1 and -sheets in compound 2. Moreover, isothermal titration calorimetry (ITC) and molecular dynamics confirmed the improved binding affinity with glyphosate strongly modulated by pH and pesticide load. Compound 1, with one alkyl chain, demonstrated notably higher catalytic activity and sensitivity linked to its pH equilibrium and structural features, marking it as particularly effective for acetylcholinesterase mimicry in pesticide detection. Density functional theory and molecular dynamics calculations showed that, when compared to the PRWG sequence, SPRWG has more unprotonated N-terminal sites due to a lower pKa, more beta-turn-like structures that improve stabilization, and more hydrogen bonds between N-(phosphonomethyl)glycine (PNG, commonly known as glyphosate) and aggregates across a wide pH range and P/L, which explains its enhanced reactivity in Ellman’s test and better inhibitory effects under the influence of PNG. Our results suggest that serine-functionalized lipopeptides have great potential as biomimetic sensors in environmental monitoring.
|
Mar 2025
|
|
I20-Scanning-X-ray spectroscopy (XAS/XES)
|
Diamond Proposal Number(s):
[19223]
Open Access
Abstract: High-charge micas exhibit improved adsorption properties and are a promising alternative clay material for the engineered barrier in deep geological repositories. When combined with Eu3+ cations, they serve as an in situ luminescent probe for tracking the physical–chemical changes occurring in this engineered barrier over the long term. Therefore, a better understanding of the local environment of the lanthanide is highly desirable to comprehend the specific behavior of these systems. A combination of different techniques, (X-ray diffraction, thermogravimetry, fluorescence, and X-ray absorption spectroscopy), has allowed the study of the local environment of two luminescent lanthanide cations, Eu3+ and Gd3+, embedded in the galleries of two high-charge micas with different Si/Al tetrahedral ratio. The results show that the hydration state of these cations is primarily influenced by the layer charge of the aluminosilicate, and secondarily by the cation’s hydration enthalpy. High-charge micas doped with trivalent lanthanide cations are more hydrated compared to the original clays with Na+ in the interlayer. Nevertheless, both Eu3+ and Gd3+ are adsorbed as inner-sphere complexes in the galleries of high-charge micas. They are located inside the distorted hexagonal cavity in all cases, coordinated by 3 oxygens from the tetragonal sheet, one fluorine from the octahedral sheet, and by 2–4 oxygens from water molecules, all at distances around 2.4 Å. An additional oxygen atom at a distance of 3.45–3.50 Å, is proposed from an H2O molecule in the second coordination shell.
|
Jan 2025
|
|
B18-Core EXAFS
E01-JEM ARM 200CF
|
Diamond Proposal Number(s):
[23723, 17198]
Abstract: Electrochemical nitrate (NO3−) reduction reaction (NO3−RR) to ammonium (NH4+) or nitrogen (N2) provides a green route for nitrate remediation. However, nitrite generation and hydrogen evolution reactions hinder the feasibility of the process. Herein, dual single atom catalysts were rationally designed by introducing Ag/Bi/Mo atoms to atomically dispersed Nisingle bondNsingle bondC moieties supported by nitrogen-doped carbon nanosheet (NCNS) for the NO3−RR. Ni single atoms loaded on NCNS (Ni/NCNS) tend to reduce NO3− to valuable NH4+ with a high selectivity of 77.8 %. In contrast, the main product of NO3−RR catalyzing by NiAg/NCNS, NiBi/NCNS, and NiMo/NCNS was changed to N2, giving rise to N2 selectivity of 48.4, 47.1 and 47.5 %, respectively. Encouragingly, Ni/NCNS, NiBi/NCNS, and NiAg/NCNS showed excellent durability in acidic electrolytes, leading to nitrate conversion rates of 70.3, 91.1, and 93.2 % after a 10-h reaction. Simulated wastewater experiments showed that NiAg/NCNS could remove NO3− up to 97.8 % at −0.62 V after 9-h electrolysis. This work afforded a new strategy to regulate the reaction pathway and improve the conversion efficiency of the NO3−RR via engineering the dual atomic sites of the catalysts.
|
Aug 2024
|
|
B21-High Throughput SAXS
|
Open Access
Abstract: Achieving a controlled preparation of nanoparticle superstructures with spatially periodic arrangement, also called superlattices, is one of the most intriguing and open questions in soft matter science. The interest in such regular superlattices originates from the potentialities in tailoring the physicochemical properties of the individual constituent nanoparticles, eventually leading to emerging behaviors and/or functionalities that are not exhibited by the initial building blocks. Despite progress, it is currently difficult to obtain such ordered structures; the influence of parameters, such as size, softness, interaction potentials, and entropy, are neither fully understood yet and not sufficiently studied for 3D systems. In this work, we describe the synthesis and characterization of spatially ordered hierarchical structures of coated cerium oxide nanoparticles in water suspension prepared by a bottom-up approach. Covering the CeO2 surface with amphiphilic molecules having chains of appropriate length makes it possible to form ordered structures in which the particles occupy well-defined positions. In the present case superlattice arrangement is accompanied by an improvement in photoluminescence (PL) efficiency, as an increase in PL intensity of the superlattice structure of up to 400 % compared with that of randomly dispersed nanoparticles was observed. To the best of our knowledge, this is one of the first works in the literature in which the coexistence of 3D structures in solution, such as face-centered cubic (FCC) and Frank-Kasper (FK) phases, of semiconductor nanoparticles have been related to their optical properties.
|
Apr 2024
|
|
