Photo-responsive supramolecular polymer bottle-brushes: The key role of the solvent on self-assembly and responsiveness.

Hypothesis: Supramolecular polymer bottlebrushes (SPBs) consist in the 1D self-assembly of building blocks composed of a self-assembling core with pendant polymer arms. Kinetic hurdles often hinder their stimuli-responsiveness in solution. Changing the nature of the solvent should alleviate these hurdles by modulating the self-association strength, leading to stimuli-responsive SPBs.

Role of the Protein Corona in the Colloidal Behavior of Microplastics.

Microparticles of polyethylene and polypropylene are largely found in aquatic environments because they are the most produced and persistent plastic materials. Once in biological media, they are covered by a layer of molecules, the so-called corona, mostly composed of proteins. A yeast protein extract from was used as a protein system to observe interactions in complex biological media.

Vapor Phase Ammonia Curing to Improve the Mechanical Properties of Antireflection Optical Coatings Designed for Power Laser Optics.

Projects of inertial confinement fusion using lasers need numerous optical components whose coatings allow the increase in their transmission and their resistance to high laser fluence. A coating process based on the self-assembly of sol-gel silica nanoparticles and a post-treatment with ammonia vapor over the surfaces of the optical components ("ammonia curing process") was developed and successfully optimized for industrial production. Manufacturing such antireflective coatings has clear advantages: (i) it is much cheaper than conventional top-down processes; (ii) it is well adapted to large-sized optical components and large-scale production; and (iii) it gives low optical losses in transmission and high resistances to laser fluence.

Correction: Galenic lab-on-a-chip concept for lipid nanocapsules production.

Correction for 'Galenic Lab-on-a-Chip concept for lipid nanocapsules production' by Nicolas Rolley , , 2021, , 11899-11912, DOI: 10.1039/D1NR00879J.

Galenic Lab-on-a-Chip concept for lipid nanocapsules production.

The continuous production of drug delivery systems assisted by microfluidics has drawn a growing interest because of the high reproducibility, low batch-to-batch variations, narrow and controlled particle size distributions and scale-up ease induced by this kind of processes. Besides, microfluidics offers opportunities for high throughput screening of process parameters and the implementation of process characterization techniques as close to the product as possible. In this context, we propose to spotlight the GALECHIP concept through the development of an instrumented microfluidic pilot considered as a Galenic Lab-on-a-Chip to formulate nanomedicines, such as lipid nanocapsules (LNCs), under controlled process conditions.

Design of tethered bilayer lipid membranes, using wet chemistry via aryldiazonium sulfonic acid spontaneous grafting on silicon and chrome.

We describe a bottom-up surface functionalization to design hybrid molecular coatings that tether biomembranes using wet chemistry. First, a monolayer was formed by immersion in a NH-Ar-SOH solution, allowing aryldiazonium salt radicals to spontaneously bind to it via strong C bonding. After formation of the air-stable and dense molecular monolayer (-Ar-SOH), a subsequent activation was used to form highly reactive -Ar-SOCl groups nearly perpendicular to the monolayer.

Electrodes for Membrane Surface Science. Bilayer Lipid Membranes Tethered by Commercial Surfactants on Electrochemical Sensors.

Commercial surfactants, which are inexpensive and abundant, were covalently grafted to flat and transparent electrodes, and it appears to be a simple functionalization route to design biomembrane sensors at large-scale production. Sparsely tethered bilayer lipid membranes (stBLM) were stabilized using such molecular coatings composed of diluted anchor-harpoon surfactants that grab the membrane with an alkyl chain out of a PEGylated-hydrogel layer, which acts as a soft hydration cushion. The goal of avoiding the synthesis of complex organic molecules to scale up sensors was achieved here by grafting nonionic diblock oligomers (Brij58 = C H(OCHCH) OH with x = 16 and n = 23) and PEO short chains ((OCHCH) OH with n = 9 and n = 23) from their hydroxyl (-OH) end-moiety to a monolayer of -Ar-SOCl groups, which are easy to form on electrodes (metals, semiconducting materials, .

Surface functionalization determines behavior of nanoplastic solutions in model aquatic environments.

Plastic debris are classified as a function of their size and recently a new class was proposed, the nanoplastics. Nano-sized plastics have a much greater surface area to volume ratio than larger particles, which increases their reactivity in aquatic environment, making them potentially more toxic. Only little information is available about their behavior whereas it crucially influences their toxicity.

Grafting Commercial Surfactants (Brij, CiEj) and PEG to Electrodes via Aryldiazonium Salts.

Grafting commercial surfactants appears to be a simple way to modify electrodes and conducting interfaces, avoiding the synthesis of complex organic molecules. A new surface functionalization route is presented to build surfactant coatings with monolayer thickness grafting molecules considered as nonreactive. A monolayer of -SOCl functions (from a p-benzenesulfonyl chloride) was first electrografted.

Assessing the antimicrobial activity of polyisoprene based surfaces.

There has been an intense research effort in the last decades in the field of biofouling prevention as it concerns many aspects of everyday life and causes problems to devices, the environment, and human health. Many different antifouling and antimicrobial materials have been developed to struggle against bacteria and other micro- and macro-organism attachment to different surfaces. However the "miracle solution" has still to be found.

Fluorescent self-assembled monolayers of umbelliferone: a relationship between contact angle and fluorescence.

Self-assembled monolayers (SAMs) that contain fluorophore units are nowadays widely used to tune surface properties and design new chemical sensor chips. It is well-known that the nature of the substrate may strongly interfere with the emission properties of the grafted molecules, but the organization of the monolayer may also have an important role. To study the influence of the SAM organization on the luminescence properties, we prepared different coumarin-based derivatives endowed with tethered chains of different lengths and elaborated the corresponding SAMs on glass slides.

Dynamic arm exchange facilitates crystallization and jamming of starlike polymers by spontaneous fine-tuning of the number of arms.

The effect of dynamic arm exchange on the crystallization and the jamming of multiarm starlike polymers was studied using small angle x-ray scattering and rheology. Poly(ethylene oxide) end capped with a small hydrophobic chain formed spherical micelles in water. Dynamic arm exchange allowed rapid crystallization and caused a discontinuous liquid-solid transition in dense suspensions after cooling.

Mechanism of lipid nanodrop spreading in a case of asymmetric wetting.

Using the surface enhanced ellipsometric contrast microscopy, we follow the last stage of the spreading of egg phosphatidylcholine nanodroplets on a hydrophilic substrate in a humid atmosphere, focusing on the vanishing trilayer in terraced droplets reduced to coexisting monolayer and trilayer. We find that the line interface between them exhibits two coexisting states, one mobile and one fixed. From there, it is possible to elucidate the internal structure and the spreading mechanism of the stratified liquid in a case of asymmetric wetting, i.

Study of titanium oxide sol-gel condensation using small angle X-ray scattering.

Transparent gels prepared from an acid solution of TiOCl(2) in N,N-dimethylformamide (DMF) and water have been studied by small-angle X-ray scattering (SAXS). The sol-gel transformation of the titanium inorganic polymer was studied as a function of chemical composition of the sol and of the annealing time. Quantitative information was obtained by modeling the SAXS data with the Burford and Beaucage models.

Dynamics of bulk fluctuations in a lamellar phase studied by coherent x-ray scattering.

Using x-ray photon correlation spectroscopy, we studied the layer fluctuations in the lamellar phase of an ionic lyotropic system. We measured the relaxation rate of in-plane (undulation) fluctuations as a function of the wave vector. Static and dynamic results obtained during the same experiment were combined to yield the values of both elastic constants of the lamellar phase (compression and bending moduli) as well as that of the sliding viscosity.

The role of counterions on the elasticity of highly charged lamellar phases: a small-angle x-ray and neutron-scattering determination.

The structure and fluctuations of the swollen L(alpha) lamellar phase of highly charged surfactant didodecyldimethylammonium halide fluid bilayers (DDA+X-) are studied using high-resolution small-angle x-ray scattering and medium-resolution, high-contrast small-angle neutron-scattering. The Caille parameter eta, as a function of the swelling (L(alpha) periodicity d), was determined from the full q-range fits of the measured scattering profiles for three different counterions (X- = Cl-, Br-, and NO3-). This parameter quantifies the amplitude of the membrane fluctuations within the Landau-de Gennes smectic-A linear elasticity theory.

Biomolecular and amphiphilic films probed by surface sensitive X-ray and neutron scattering.

In this review article we discuss the thin film analytical techniques of interface sensitive X-ray and neutron scattering applied to aligned stacks of amphiphilic bilayers, in particular phospholipid membranes in the fluid L(alpha) phase. We briefly discuss how the structure, composition, fluctuations and interactions in lipid or synthetic membranes can be studied by modern surface sensitive scattering techniques, using X-rays or neutrons as a probe. These techniques offer an in-situ approach to study lipid bilayer systems in different environments over length scales extending from micrometer to nanometer, both with and without additional membrane-active molecules such as amphiphilic peptides or membrane proteins.

A highly unusual palindromic transmembrane helical hairpin formed by SARS coronavirus E protein.

The agent responsible for the recent severe acute respiratory syndrome (SARS) outbreak is a previously unidentified coronavirus. While there is a wealth of epidemiological studies, little if any molecular characterization of SARS coronavirus (SCoV) proteins has been carried out. Here we describe the molecular characterization of SCoV E protein, a critical component of the virus responsible for virion envelope morphogenesis.