Biomacromolecules Update: Welcome to Our New Editors and New Procedure for Review Submission

Despite the pandemic and the difficulties posed by it to researchers around the world, 2020 has been a great year for Biomacromolecules as it achieved some significant milestones in the past year. First, Biomacromolecules reached the highest level in history with a record impact factor of above 6.0. Furthermore, what a year I have had! I have truly enjoyed my first year as Editor-in-Chief. Thanks to all at the ACS, from the journal office to production to marketing to the leadership at ACS Publications, for making the transition smooth and providing me all the support to continue to expand the influence of Biomacromolecules. A special thanks to our Managing Editor, Dr. Paulomi Majumder, for her unwavering support. In an effort to provide our community with fast, smooth, fair, and ethical editing and review processes, we have implemented and continue to implement several processes. For instance, we now have established a new procedure to optimize the process for a review proposal. Even if the majority of reviews are solicited by members of the editorial board in accordance with editorial policy, the editorial office welcomes suggestions for reviews that may be suitable for the journal

Polymer vesicles (from virus to cell biomimicry)

Les polymersomes, obtenus par auto-assemblage en solution aqueuse de copolymères à blocs amphiphiles en structure vésiculaire, sont présentés comme d excellent mimes synthétiques des virus, dont les propriétés membranaires principalement élasticité, perméabilité, fonctionnalité- peuvent être très proches. Il y a ainsi un fort engouement quant à leur utilisation en biotechnologie et surtout en vectorisation d actifs pharmaceutiques ou cosmétiques. Afin d aller encore plus loin dans le biomimétisme ou la bio-inspiration, une étape devait être franchie : encapsuler ces polymersomes les uns dans les autres. Ce cloisonnement ou multi-compartimentalisation permet de mimer cette fois la structure d une cellule dite eukaryote, elle-même constituée de compartiments internes (organelles) et d un cytoplasme (lui conférant entre autres une certaine stabilité mécanique) contenues dans le compartiment externe représenté par la membrane cellulaire. Toutefois, l obtention d un simple mime structural d une structure si complexe représente déjà un challenge en soi, nécessitant maîtrise de la physico-chimie des systèmes, de la stabilisation des interfaces et des outils de formulation. Une méthode d émulsion-centrifugation a été développée et a permis d obtenir de telles structures compartimentalisées (mimes d organelles) à cavité gélifiée (mime de cytoplasme). Finalement, différentes voies d exploitation de ces systèmes sont présentées, allant de l encapsulation multiple, la libération contrôlée jusqu au développement de réactions enzymatiques en cascade confinées, mimant ainsi le métabolisme cellulaire.Amphiphilic block copolymers self-assemble in water into vesicles, coined polymersomes ; these vesicles are described as excellent synthetic mimics of viral capsids due to the resemblance of their respective membrane properties (in terms of elasticity, permeability, and functionality). As a result, they were massively investigated over the last years regarding applications in biotechnology and more particularly for the targeted delivery of pharmaceutical or cosmetic actives.In order to go further towards bio-inspiration and cell biomimicry, the next step required the encapsulation of polymersomes in other polymersomes. This multicompartmentalization indeed enables to mimic the structure of an eukaryotic cell; an outer cellular membrane compartment encloses internal compartments (organelles) and a cytoplasm responsible amongst others for a certain mechanic stability. However, alone the controlled formation of a system mimicking such a complex structure represents a technological challenge in terms of control over the physical chemistry of these systems, the stabilization of their interfaces and their formulation. A formation method based upon an emulsion-centrifugation has been developed and enabled the formation of such multicompartmentalized structures (organelle mimics) with a gelified lumen (cytoplasm mimic). Finally, various potential applications of these systems are presented: from multiple encapsulation, controlled drug release, to the development of enzymatic and confined cascade reactions that mimick the cellular metabolism.BORDEAUX1-Bib.electronique (335229901) / SudocSudocFranceF

Assemblages de copolymères à blocs pour la vectorisation de siRNA

Les siRNA sont des molécules double brin d acide ribonucléique capables d inhiber l expression d un gène spécifique, présentant ainsi un fort potentiel thérapeutique pour les maladies génétiques, les cancers et les infections virales. Cependant, son utilisation in vivo est restreinte par sa sensibilité à la dégradation enzymatique. Le projet de thèse consiste à créer un système de vectorisation des siRNA pour des applications in vivo. Nous avons synthétisé des copolymères à blocs amphiphiles biocompatibles et biodégradables capable de s auto-assembler en diverses structures et d encapsuler les siRNA. Les propriétés physico-chimiques des assemblages formées et l évaluation cellulaire préliminaire est réaliséeAmphiphilic block copolymers are molecules composed of hydrophilic and hydrophobic segments having the capacity to spontaneously self-assemble into a variety of supramolecular structures like micelles and vesicles. Here, we propose an original way to self-assemble amphiphilic block copolymers into a supported bilayer membrane for defined coating of nanoparticles. The heart of the method rests on a change of the amphiphilicity of the copolymer that can be turned off and on by varying the polarity of the solvent. In this condition, the assembly process can take advantage of specific molecular interactions in both organic solvent and water. The higher gene silencing activity of the copolymer-modified complexes over the complexes alone shows the potential of this new type of nanoconstructs for biological applications, especially for the delivery of therapeutic biomolecules.BORDEAUX1-Bib.electronique (335229901) / SudocSudocFranceF

Organogels from trehalose difatty esters amphiphiles

International audienceSaccharide diesters have been recently shown to be excellent gelators of vegetable oils. In this paper, different fatty acid trehalose diesters were synthesized by a selective enzymatic transesterification performed only on the primary hydroxyl group of the trehalose. The resulting trehalose diesters demonstrated their ability to self-assemble in a large variety of edible vegetable oils with a minimum gelation concentration of 0.25 wt%/v. Microscopic analysis and X-ray scattering studies indicate that the gels are obtained by the self-assembly of trehalose diesters in crystalline fibers constituting the tridimensional network. The rheological study revealed that the properties of the gels depend on the kind of fatty acid grafted on the trehalose but are also influenced by the vegetable oil composition

Peptide Materials

Over the past three decades, the field of peptide-based materials has been rapidly expanding and evolving, becoming a multidisciplinary area, with new developments and applications being consistently discovered. The purpose of this Peptide Materials Special Issue is to highlight research presented at the first Gordon Research Conference on Peptide Materials in January, 2023. Consequently, we invited eminent scientists with primary research interests in Peptide Materials to contribute original research articles or short reviews in this area. This thematic issue is focused on the materials aspects of peptides and their derivatives and mimics, including both fundamental research in peptide design, synthesis, assembly, micellization, gelation, and coacervation, as well as disparate technological applications, including functional materials for energy storage, catalysis, drug delivery, regenerative medicine, adhesion, protein purification, and nanotechnology. As peptides are composed of amino acids─the fundamental building blocks of proteins─they serve as a natural bridge between small-molecule supramolecular assemblies and large biomacromolecular constructs. Their ability to adopt well-defined secondary and tertiary structures, undergo hierarchical self-assembly, and exhibit tunable biochemical properties and distinct structural features highlights their importance and relevance within the broader landscape of biomacromolecular research. The peptide materials field has become a well-established, interdisciplinary area that attracts chemists, chemical engineers, material scientists, physicists, and biomedical engineers. The papers collected in this special issue demonstrate the growing recognition of peptides, polypeptides, proteins, and their derivatives and mimics as a versatile and critical class of biomacromolecules, poised to drive continued growth and innovation across diverse scientific and technological disciplines

Cellulose-Assisted Formation of 2D Hybrid Halide Perovskite Nanocrystals with Enhanced Stability for Light-Emitting Devices

A common approach to enhance the stability of metal halide perovskites (MHPs) implemented in optical and optoelectronic devices is to incorporate polymer additives into the perovskite layer. A β-(1,4) cellulose oligosaccharide (COS) synthesized by mechanocatalytic depolymerization of cellulose has been incorporated to films of the BA2MA4Pb5I16 (BA = n-butylammonium and MA = methylammonium) two-dimensional (2D) Ruddlesden-Popper (RP) hybrid perovskite. Scanning Electron Microscopy (SEM) images displayed a three-fold reduction of the 2D RP perovskite grains (≈30–40 nm), close to the quantum confinement scale. The analysis of the dark J–V curves of single carrier devices by using the space charge limited current (SCLC) method resulted in a rise of the defect concentration. A notable 14-fold increase in the photoluminescence (PL) signal at high COS content is detected. Moreover, the analysis of the temperature dependence PL measurements (80–300 K) resulted in a larger exciton binding energy, Eb = 180 to 370 meV, at high COS content. Light emitting diodes of the 2D RP perovskites (PeLEDs) are fabricated w/o the COS compound. The stability test performed under operation (5 V) displays 20 times higher operational lifetimes at high COS content while the luminance is also increased in the devices with the COS compound

Controlling Polymersome Size through Microfluidic-Assisted Self-Assembly: Enabling 'Ready to Use' formulations for biological applications

The self-assembly of poly(ethylene glycol)-block-poly(trimethylene carbonate) PEG-b-PTMC copolymers into vesicles, also referred as polymersomes, was evaluated by solvent displacement using microfluidic systems. Two microfluidic chips with different flow regimes (micromixer and Herringbone) were used and the impact of process conditions on vesicle formation was evaluated. As polymersomes are sensitive to osmotic variations, their preparation under conditions allowing their direct use in biological medium is of major importance. We therefore developed a solvent exchange approach from DMSO (Dimethylsulfoxide) to aqueous media with an osmolarity of 300 mOsm.L-1, allowing their direct use for biological evaluation. We evidenced that the organic/aqueous solvent ratio does not impact vesicle size, but the total flow rate and copolymer concentration have been observed to influence the size of polymersomes. Finally, nanoparticles with diameters ranging from 76 nm to 224 nm were confirmed to be vesicles through the use of multi-angle light scattering in combination with cryo-TEM (Cryo-Transmission Electron Microscopy) characterization