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In this work, we studied TEMPO-oxidized cellulose nanofibril (OCNF) suspensions in the presence of diverse surfactants. Using a combination of small angle neutron scattering (SANS) and rheology, we compared the physical properties of the suspensions with their structural behavior. Four surfactants were studied, all with the same hydrophobic tail length but different headgroups: hexaethylene glycol

The controlled delivery of micronutrients to soil and plants is essential to increase agricultural yields. However, this is today achieved using fossil fuel-derived plastic carriers, posing environmental risks and contributing to global carbon emissions. In this work, a novel and efficient way to prepare biodegradable zinc-impregnated cellulose acetate beads for use as controlled release fertilize

The common Deep Eutectic Solvent (DES) ‘ethaline’ (1:2 choline chloride:ethylene glycol) was examined here as a basis for the self-assembly of the surfactant dodecyltrimethylammonium bromide (C12TAB). A phase diagram was constructed, showing evidence for a L1 (micellar) phase, confirmed by tensiometry to have a room temperature critical micelle concentration (CMC) of 1.2 wt.%. Small angle neutron

A series of lanthanide nitrate hydrate:urea "Type IV" deep eutectic solvents (DES; Ln = Ce, Pr, Nd) were prepared and their physical properties measured, showing very high surface tension and density, with low viscosity and glass transition temperatures. Calculated Gordon parameters were similar to water, with lower molecular volumes than "Type III" DES. The LnDES were used as reaction media for

The delivery of ibuprofen into and through the skin from novel formulations containing TEMPO-oxidized cellulose nanofibril-based (TOCN) gels was compared to that from two conventional and commercially available products. The gels were evaluated in-vitro (using both silicone membranes, and pig skin) and in-vivo in human volunteers. All gels showed consistent behaviour in a standard in vitro release

Controlling polymer thin-film morphology and crystallinity is crucial for a wide range of applications, particularly in thin-film organic electronic devices. In this work, the crystallization behavior of a model polymer, poly(ethylene oxide) (PEO), during spin-coating is studied. PEO films were spun-cast from solvents possessing different polarities (chloroform, THF, and methanol) and probed via i

The liquid structure of the archetypal Deep Eutectic Solvent (DES) reline, a 1:2 molar mixture of choline chloride and urea, has been determined at 303 K. This is the first reported liquid-phase neutron diffraction experiment on a cholinium DES. H/D isotopic substitution is used to obtain differential neutron scattering cross sections, and an Empirical Potential Structure Refinement (EPSR) model i

Hypothesis: Owing to structural similarities between sulfobetaine lipids and phospholipids it should be possible to form stable Langmuir monolayers from long tail sulfobetaines. By modification of the density of lipid tail group (number of carbon chains) it should also be possible to modulate the two-dimensional phase behaviour of these lipids and thereby compare with that of equivalent phospholip

Over the past 50 years there has been considerable progress in our understanding of biomolecular interactions at an atomic level. This in turn has allowed molecular simulation methods employing full atomistic modelling at ever larger scales to develop. However, some challenging areas still remain where there is either a lack of atomic resolution structures or where the simulation system is inheren

The characterization of structure over a wide range of length scales from atomic to microns is a common requirement for understanding the behaviour of many soft matter systems. In the case of self-assembling and colloidal materials, the final properties will depend sensitively on intermolecular as well as interparticle interactions. Experimental methods such as wide and small angle scattering, whi

This work aimed to understand the relationship between the physical properties of scattering particle layers in dye-sensitized solar cells (DSSCs) and their performance, to assist optimization of this component of the DSSC. Highly ordered anatase 2D-hexagonal mesoporous titania (meso-TiO2) nanoparticles with a high surface area and large pore size were fabricated. Meso-TiO2 was used as scattering

We currently use Convection-Enhanced Delivery (CED) of the platinum-based drug, carboplatin as a novel treatment strategy for high grade glioblastoma in adults and children. Although initial results show promise, carboplatin is not specifically toxic to tumour cells and has been associated with neurotoxicity at high infused concentrations in pre-clinical studies. Our treatment strategy requires in

Film formation and film structure in films formed on solutions of cationic surfactants with polyethylenimine is influenced by the surfactant structure, including both the tail length and the nature of the headgroup, which alter the micelle properties. Experiments: A series of cationic surfactants were synthesized and conductivity measurements were used to compare the critical micelle concentration

Beyond biomimicry! We are at a threshold where technology and life converge, where living machines modify and adapt the environments that they construct and persist within. Who is working at this frontier? How are scientists, engineers, programmers, designers and biologists converging to capture organismal construction algorithms from nature and play them back to emerging swarm robotic and digital

Improvements in the efficiency of combustion within a vehicle can lead to reductions in the emission of harmful pollutants and increased fuel efficiency. Gas sensors have a role to play in this process, since they can provide real time feedback to vehicular fuel and emissions management systems as well as reducing the discrepancy between emissions observed in factory tests and 'real world' scenari

In the past few years there has been a growth in the use of nanoparticles for stabilizing lipid membranes that contain embedded proteins. These bionanoparticles provide a solution to the challenging problem of membrane protein isolation by maintaining a lipid bilayer essential to protein integrity and activity. We have previously described the use of an amphipathic polymer (poly(styrene-co-maleic

Poly(lactide-co-glycolide)-block-poly(ethylene glycol) (PLGA-PEG) nanoparticles are commonly used as drug carriers in controlled drug release and targeting. To achieve predictable and clinically relevant volumes of drug distribution, nanoparticle size, surface charge, and especially composition and structure must be controlled. Understanding the internal structures within the particles is fundamen

Free-standing titania films were grown at the air-water interface, a novel method to synthesize robust TiO2 nanowire/nanoparticle composite films. The calcined films contain an anatase crystal phase and have a high surface area with a structure composed of one-dimensional long nanowires and mesoporous nanoparticle branches. These suggest a promising way to manufacture large areas of thick porous t

N-Oxyl mediated oxidations are becoming widely applied to the selective oxidation of a range of substrates bearing primary alcohol groups, including renewable biopolymers such as cellulose, but screening of mediators and oxidation conditions can be a laborious process, potentially limiting discovery of new mediators and/or optimised conditions for reaction. We describe a simple method for rapid vo

PLGA/PLA polymeric nanoparticles could potentially enhance the effectiveness of convective delivery of drugs, such as carboplatin, to the brain, by enabling a more sustained dosage over a longer time than otherwise possible. However, the link between the controlled release nanoparticle synthesis route, and the subsequent drug release profile obtained, is not well-understood, which hinders design o