1. A multi-scale approach linking self-aggregation & surface interactions of synthesised foulants to fouling mitigation strategies
Author: Domna-Maria Kaimaki, Barnaby HaireHugh Ryan, Guadalupe Jiménez-Serratos, Richard Marcos Alloway, Mark LittleJohn Morrison, Ibrahim Salama, Marcus Tillotson, Benjamin E. Smith, Saul Moorhouse, Tim S. Totton, Michael G. Hodges, Stephen G. Yeates, Peter Quayle, Stuart ClarkeErich A Muller and Colm Durkan
Journal: Energy Fuels
Abstract: Fouling of oil-exposed surfaces remains a crucial issue due to the continued importance of oil as the world’s primary energy source. The key perpetrators in crude oil fouling have been identified as asphaltenes, a poorly-described mixture of diverse polyfunctional molecules that form part of the heaviest fractions of oil. Asphaltenes are responsible for a decrease in oil production and energy efficiency, and an increase in the risk of environmental hazards. Hence, understanding and managing systems that are prone to fouling is of great value but constitutes a challenge due to their complexity.
2. A Facile Surface Modification Method for Synergistically Enhancing Biocompatibility and Bioactivity of Polyetheretherketone with Inducing Osteo-differentiation
Authors: Yuchen Zhu, Zhe Cao, Ying Peng, Liqiu Hu, Tankut Guney and Bin Tang
Journal: ACS Applied Materials & Interfaces
Abstract: Polyetheretherketone (PEEK) is a promising material in biomedical engineering due to its suitable mechanical properties, excellent chemical resistance and biocompatibility. However, biological inertness of PEEK limits its applications. In this study, we developed a facile approach of immersion to generating a biocompatible and bioactive PEEK that induced osteo-differentiation.
3. Influence of NaCl Concentration on Bicelle-Mediated SLB Formation
Authors: Tun Naw Sut, Joshua A. Jackman, Bo Kyeong Yoon, Soohyun Park, Kavoos Kolahdouzan, Gamaliel Junren Ma, Vladimir P. Zhdanov and Nam-Joon Cho
Abstract: The deposition of two-dimensional bicellar disks on hydrophilic surfaces is an emerging approach to fabricate supported lipid bilayers (SLBs) that requires minimal sample preparation, works at low lipid concentrations, and yields high-quality SLBs. While basic operating steps in the fabrication protocol mimic aspects of the conventional vesicle fusion method, lipid bicelles and vesicles have distinct architectural properties and understanding how experimental parameters affect the efficiency of bicelle-mediated SLB formation remains to be investigated. Herein, by using the quartz crystal microbalance-dissipation (QCM-D) and localized surface plasmon resonance (LSPR) techniques, we investigated the effect of bulk NaCl concentration on bicelle-mediated SLB formation on silicon dioxide surfaces.
4. Effect of External Salt Addition on the Structural, Morphological and Electrochemical Properties of Flexible PEDOT: PSS Based LbL Multilayered Films
Authors: Merve Okutan and HüseyinDeligöz
Journal: Colloids and Surfaces A: Physicochemical and Engineering Aspects
Abstract: This article concerns with the effect of external salt addition on the structural, morphological and electrochemical properties of linear poly(ethylene imine) (LPEI) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) based LbL assembled films that is a cathodic color changing electrode for electrochromic device. For this purpose, cationic and anionic commercial polyelectrolytes (PEs) with/without 0.3 M NaCl were deposited on PET-ITO with automatized dip coating system. From QCM-D, it was found that the multilayer deposition became larger for LbL assembled films obtained from salt-free PEs. While the dissipation change (ΔD) of (LPEI/PEDOT:PSS)10/NaCl (150 × 10-6) exhibited relatively soft/flexible structure compared to the (LPEI/PEDOT:PSS)10 (110 × 10-6), ΔD changes became more obvious during PEDOT:PSS adsorption.
5. Layer-by-layer polyelectrolyte architectures with ultra-fast and high loading/release properties for copper ions
Authors: Florin Bucatariu, Claudiu-Augustin Ghiorghita, Dana Schwarz, Tudor Boita and Marcela Mihai
Journal: Colloids and Surfaces A: Physicochemical and Engineering Aspects
Abstract: The solid surfaces functionalization with high number of organic moieties from polymer chains became an interesting route to obtain new materials which can load/release a wide variety of chemical compounds due to the stimuli responsiveness (pH, ionic strength, temperature, solvent quality) of the organic part. Weak polyelectrolytes are very useful materials in construction of composite systems with thin layer-by-layer organic films on the surface with high potential in solid phase extraction. Herein, two facile strategies to modify silica microparticlesurfaces with single branched poly(ethyleneimine) (PEI) multilayers are reported, the formed composites having ultra-fast response and high capacity for multiple loading/release of copper ions from aqueous solutions.
6. The stabilization of food grade copper-chlorophyllin in low pH solutions through association with anionic polysaccharides
Authors: Michael J.Selig, Sara Gamaleldin, Giovana B. Celli, Meghan A. Marchuk, Detlef-M. Smilgies and Alireza Abbaspourrad
Journal: Food Hydrocolloids
Abstract: This work investigates the potential for anionic polysaccharides, such as alginate and xanthan gum, to impart solution and color stability to dilute solutions of copper chlorophyllin (Cu-ChP) buffered at acidic pH. Under cold storage, both polysaccharides tested were shown with sufficient loading to mitigate Cu-ChP aggregation at pH 3.0 and 5.0; xanthan gum use required lower loadings than the sodium alginate tested. Analysis of polysaccharide stabilized Cu-ChP solutions by dynamic light scattering suggests complex formation does occur; this is likely driven by electrostatic interactions between copper cations coordinated at the pigment core and the heavily anionic surfaces of the polyccharide matrices created by the large number of uronic acid substituents on the hydrocolloids.
7. Novel biodegradable and non-fouling systems for controlled-release based on poly (ε-caprolactone)/Quercetin blends and biomimetic bacterial S-layer coatings
Authors: Eva Sanchez-Rexach, Jagoba Iturri, Jorge Fernandez, Emilio Meaurio, Jose-Luis Toca-Herrera and Jose-Ramon Sarasua
Journal: RSC Advances
Abstract: Quercetin is a strong antioxidant with low bioavailability due to its high crystallinity. A further drawback is that Quercetin has potentially toxic effects at high concentrations. To improve this low water solubility, as well as control the concentration of the flavonoid in the body, Quercetin is incorporated into a polymeric matrix to form an amorphous solid dispersion (ASD) stable enough to resist the recrystallization of the drug. For this purpose, miscible poly(ε-caprolactone) (PCL) and Quercetin (Q) blends are prepared, provided that they have complementary interacting groups.
8. Design and Testing of a Bending‐Resistant Transparent Nanocoating for Optoacoustic Cochlear Implants
Authors: Alessandra Griffo, Yingying Liu, Riitta Mahlberg, Dr. Hanna‐L. Alakomi, Dr. Leena‐S. Johansson and Dr. Roberto Milani
Journal: Chemistry Open
Abstract: A nanosized coating was designed to reduce fouling on the surface of a new type of cochlear implant relying on optoacoustic stimulation. This kind of device imposes novel design principles for antifouling coatings, such as optical transparency and resistance to significant constant bending. To reach this goal we deposited on poly(dimethylsiloxane) a PEO‐based layer with negligible thickness compared to the curvature radius of the cochlea.
9. Reversible membrane-tethering by ZipA determines FtsZ polymerization in two and three dimensions
Authors: Marta Sobrinos-Sanguino, Marisela Vélez, Ralf P. Richter and Germán Rivas
Abstract: In most bacteria, the early step of septum formation implies the association of soluble FtsZ polymers to the cytoplasmic membrane. ZipA, together with FtsA, provide membrane tethering to FtsZ in Escherichia coli, forming a dynamic proto-ring that serves as an assembly scaffold for the remaining elements of the divisome. Despite their importance for bacterial cell division, multivalent interactions between proto-ring elements at membrane surfaces remain poorly characterized in quantitative terms. Here we measured the binding of FtsZ to ZipA incorporated in supported lipid bilayers at controlled densities by using a combination of biophysical surface-sensitive techniques (quartz crystal microbalance and spectroscopic ellipsometry) and analyzed how ZipA density and FtsZ concentration control the state of assembly of FtsZ.