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Continuous production of cellulose microbeads by rotary jet atomization

The replacement of plastic microbeads with biodegradable alternatives is essential due to the environmental persistence of plastics and their accumulation within the human food chain. Hypothesis: Cellulose microbeads could be such alternative, but their production is hindered by the high viscosity of cellulose solutions. It is expected that this viscosity can be harnessed to induce filament thinni

Production of sub-10 micrometre cellulose microbeads using isoporous membranes

The production of sub-10 µm cellulose microbeads via membrane emulsification using isoporous membranes is reported here for the first time. Poly(ethylene terephthalate) membranes, with defined interpore distances, pore diameters and straight-through pores were fabricated via photolithography. A dispersed phase of 8 wt% cellulose solution was extruded through the membrane pores, forming, due to she

Enzyme-Functionalized Cellulose Beads as a Promising Antimicrobial Material

The extensive use of antibiotics over the last decades is responsible for the emergence of multidrug-resistant (MDR) microorganisms that are challenging health care systems worldwide. The use of alternative antimicrobial materials could mitigate the selection of new MDR strains by reducing antibiotic overuse. This paper describes the design of enzyme-based antimicrobial cellulose beads contai

Ensilicated tetanus antigen retains immunogenicity : in vivo study and time-resolved SAXS characterization

Our recently developed ensilication approach can physically stabilize proteins in silica without use of a pre-formed particle matrix. Stabilisation is done by tailor fitting individual proteins with a silica coat using a modified sol-gel process. Biopharmaceuticals, e.g. liquid-formulated vaccines with adjuvants, frequently have poor thermal stability; heating and/or freezing impairs their potency

Impact of wormlike micelles on nano and macroscopic structure of TEMPO-oxidized cellulose nanofibril hydrogels

In this work, we investigated the effect of adding surfactant mixtures on the rheological properties of TEMPO-oxidized cellulose nanofibril (OCNF) saline dispersions. Three surfactant mixtures were studied: cocamidopropyl betaine (CAPB)/sodium dodecyl sulfate (SDS), which forms wormlike micelles (WLMs); cocamidopropylamine oxide (CAPOx)/SDS, which forms long rods; and CAPB/sodium lauroyl sarcosina

Hydrophobization of Cellulose Nanocrystals for Aqueous Colloidal Suspensions and Gels

Surface hydrophobization of cellulose nanomaterials has been used in the development of nanofiller-reinforced polymer composites and formulations based on Pickering emulsions. Despite the well-known effect of hydrophobic domains on self-assembly or association of water-soluble polymer amphiphiles, very few studies have addressed the behavior of hydrophobized cellulose nanomaterials in aqueous medi

Adsorption of a styrene maleic acid (SMA) copolymer-stabilized phospholipid nanodisc on a solid-supported planar lipid bilayer

Over recent years, there has been a rapid development of membrane-mimetic systems to encapsulate and stabilize planar segments of phospholipid bilayers in solution. One such system has been the use of amphipathic copolymers to solubilize lipid bilayers into nanodiscs. The attractiveness of this system, in part, stems from the capability of these polymers to solubilize membrane proteins directly fr

Filler size effect in an attractive fibrillated network : A structural and rheological perspective

The effect of the filler size on the structural and mechanical properties of an attractive fibrillated network composed of oxidised cellulose nanofibrils (OCNF) in water was investigated. Silica nanoparticles with a diameter of ca. 5 nm (SiNp5) and and ca. 158 nm (SiNp158) were chosen as non-interacting fillers of the OCNF network. These filler sizes were chosen, respectively, to have a particle s

Toward Process-Resilient Lignin-Derived Activated Carbons for Hydrogen Storage Applications

Activated carbons are promising sorbents that have been heavily investigated for the physisorptive storage of hydrogen. The industrial process for production of activated carbons is finely tuned and requires a reliable and uniform feedstock. While the natural biopolymer lignin, a byproduct of several industries, has received increasing interest as a potentially sustainable and inexpensive activate

Cationic surfactants as a non-covalent linker for oxidised cellulose nanofibrils and starch-based hydrogels

Rheological properties of hydrogels composed of TEMPO-oxidised cellulose nanofibrils (OCNF)-starch in the presence of cationic surfactants were investigated. The cationic surfactants dodecyltrimethylammonium bromide (DTAB) and cetyltrimethylammonium bromide (CTAB) were used to trigger gelation of OCNF at around 5 mM surfactant. As OCNF and DTAB/CTAB are oppositely charged, an electrostatic attract

Bacteriophage M13 Aggregation on a Microhole Poly(ethylene terephthalate) Substrate Produces an Anionic Current Rectifier : Sensitivity toward Anionic versus Cationic Guests

Bacteriophage material (M13, wild-type) deposited as a film onto a poly(ethylene terephthalate) (PET) substrate (6 μm thick with a 20 μm diameter laser-drilled microhole) has been investigated for ion conductivity and ionic current rectification effects for potential applications in membranes. The M13 aggregate membrane forms under acidic conditions (in aqueous 10 mM acids) and behaves like a micr

Charge-driven interfacial gelation of cellulose nanofibrils across the water/oil interface

Interfacial gels, obtained by the interaction of water-dispersible oxidised cellulose nanofibrils (OCNF) and oil-soluble oleylamine (OA), were produced across water/oil (W/O) interfaces. Surface rheology experiments showed that the complexation relies on the charge coupling between the negatively-charged OCNF and OA. Complexation across the W/O interface was found to be dependent on the ζ-potentia

Influence of Aromatic Structure on the Thermal Behaviour of Lignin

Lignin, a natural biopolymer and abundant by-product, is a particularly promising feedstock for carbon-based materials and a potentially sustainable alternative to phenolic resins, which are typically derived from crude oil. The source and method used to isolate lignin have a large impact on the thermal properties of the polymer, and can affect resultant materials prepared from lignin. Previous in

Structure and implications

This chapter reviews the evolving understanding of structuring in deep eutectic solvents (DESs) with a focus on choline chloride-based systems as the most popularly studied DES. Recent literature is critically evaluated to attempt to identify common aspects of the structure and interactions in different DESs to improve our fundamental understanding of these solvents.

Assessing molecular simulation for the analysis of lipid monolayer reflectometry

Using molecular simulation to aid in the analysis of neutron reflectometry measurements is commonplace. However, reflectometry is a tool to probe large-scale structures, and therefore the use of all-atom simulation may be irrelevant. This work presents the first direct comparison between the reflectometry profiles obtained from different all-atom and coarse-grained molecular dynamics simulations.

Nano-encapsulated Escherichia coli Divisome Anchor ZipA, and in Complex with FtsZ

The E. coli membrane protein ZipA, binds to the tubulin homologue FtsZ, in the early stage of cell division. We isolated ZipA in a Styrene Maleic Acid lipid particle (SMALP) preserving its position and integrity with native E. coli membrane lipids. Direct binding of ZipA to FtsZ is demonstrated, including FtsZ fibre bundles decorated with ZipA. Using Cryo-Electron Microscopy, small-angle X-ray

In Situ Monitoring of Nanoparticle Formation during Iridium-Catalysed Oxygen Evolution by Real-Time Small Angle X-Ray Scattering

Real-time Small Angle X-Ray Scattering (SAXS) has been used to investigate the homogeneity of a series of molecular iridium complexes during water oxidation catalysis in aqueous NaIO4 solution through a continuous flow cell. The results obtained for the unstable [Cp*Ir(OH2)3]2+ precursor forming amorphous IrOx nanoparticles (NPs) in-situ validate and complement previous Dynamic Light Scattering (D

Temperature and concentration effects on decyltrimethylammonium micelles in water

Wide-angle neutron scattering experiments combined with Empirical Potential Structural Refinement modelling have been used to study the detailed structure of decyltrimethylammonium bromide (C10TAB) micelles at two different temperatures; 25°C and 50°C and two concentrations; 0.4 and 0.8 M in water. At higher temperature, the micelles become smaller, and fewer counterions bind to the micelle surfac

Influence of levofloxacin and clarithromycin on the structure of DPPC monolayers

Research on lipid/drug interactions at the nanoscale underpins the emergence of synergistic mechanisms for topical drug administration. The structural understanding of bio-mimetic systems employing 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) as a lung surfactant model mixed with antibiotics, as well as their biophysical properties, is of critical importance to modulate the effectiveness of

An introduction to classical molecular dynamics simulation for experimental scattering users

Classical molecular dynamics simulations are a common component of multi-modal analyses of scattering measurements, such as small-angle scattering and diffraction. Users of these experimental techniques often have no formal training in the theory and practice of molecular dynamics simulation, leading to the possibility of these simulations being treated as a `black box' analysis technique. This ar