The objective of GASP is the development of 100% biobased polylactide materials including cellulose nanostructures with designed barrier properties for oxygen, CO2, water or organic vapors. These materials are targeted on high added value applications in the packaging industry. GASP is deliberately positioned on fully biobased and biodegradable commercially available polymers. It volunteers thereby to contribute to the solutions needed for developing sustainable growth of manufacturing industries by innovation and accompanying their transition versus the use of renewable resources. Organic polymers have already high market share in the packaging sector and their comparatively low gas and vapor barrier properties are one of the limitations to expansion towards novel applications in specialties. Precisely low barrier properties are also one of the major hurdles for novel biodegradable and biobased polymers entering the high volume market packaging. Nanostructures allow for tailoring material properties on the macromolecular scale and offer thus opportunity for development of innovative composites. Nanocelluloses are now available in industrial amounts and their high barrier properties to oxygen have already been shown. However, their potential is not exploited industrially today because industrial know-how for transformation with common plastics converters methodology is lacking. GASP tackles the two major hurdles for the fabrication of biobased barrier polymers, i) lack of scientific knowledge on the role of the nanofiller/polymer interfaces and ii) lack of plastics processing knowledge for the creation of performing polymer composites. GASP proposes the following strategy: On the molecular scale, GASP aims to develop nanocellulose surface grafting processes for tailoring the nanocellulose/polymer interface with two goals i) compatibilizing both partners and ii) engineering the interfaces by grafting of nanocellulose surfaces with molecules able to selectively trap permeants for improving barrier properties. On the processing scale, GASP seeks to develop nanocellulose processing techniques in the aim to create optimized material architectures. For that goal a simulation driven approach will also be used to define the most appropriate architectures for improved barrier properties. To rise to this challenge a highly competitive consortium of industrial and academic actors has joined. Leading French academic laboratories in polymer processing (PIMM), gas barrier properties of nanocomposites and modeling (IMP), diffusion/solubility properties of polymers (PBS), food/polymer interactions (GENIAL), surface chemistry (ICMMO) and characterization and modification of nanocelluloses (LGP2) will work hand in hand with two start ups in creation of specific molecular traps (Ajelys) and production of tailor-made nanocelluloses (Inofib), and two companies specialized in thermoforming of food containers (CGL Pack) and film fabrication and complexing (Wipak). The outcomes of GASP will be on the academic level advancing the state of the art of our common knowledge on transport properties and mechanisms on very localized interfaces between nanostructures and polymers. The scientific results will be brought to a large community of users by communication in scientific congresses and teaching actions, professional events and science communication to public. On the industrial level, GASP aims on the creation of two pilot materials able to be transferred to industrial pilot scale processes and directly impacting the business of the associated companies. For the consumer GASP will pave the way towards renewable packaging materials complying with the highest standards of performance and safety.

-OMe-Glucuronoxylane is the main hemicellulose in hardwoods. Although it is very abundant (20 to 25% of the mass of dry wood), this polymer with particularly interesting chemical properties remains little valorised today. For several years, the LABCiS laboratory (UR22722) has been developing eco-extraction processes and exploring innovative ways to recover this polymer. The LABCiS laboratory is also an expert in phototherapy, in particular applied to the treatment of cancer or microbial infections. The Polymers, Biopolymers, Surfaces laboratory (PBS, UMR CNRS 6270) federates numerous skills around polymers and their interactions with living organisms in order to develop macromolecular chemistry strategies, coupled or not with physical, physicochemical and biological approaches, for the elaboration of innovative high-performance polymers. By joining forces within the framework of the HydroXyl-PACT project, the two laboratories LABCiS and PBS are pooling their expertise at the frontiers of several disciplines (organic chemistry, physics, biology) to develop new hydrogels based on 4-OMe-Glucuronoxylane. The challenges are twofold: - to develop, through eco-responsible chemistry approaches, innovative hydrogels with a wide range of applications based on a xylan that is very abundant and has great potential but is not very well valorised. - to propose an innovative multifunctional bioactive platform opening the way to new effective dressings for multi-resistant bacteria, a major public health problem. Indeed, the hydrogels will be functionalized by photosensitizers of natural or synthetic origin and by natural antibiotic molecules (phenols, polyphenols, aminosides...), which can be released under the effect of external stimuli, to lead to new materials studied for applications in photodynamic antimicrobial chemotherapy (PACT). Such hydrogels could be advantageously used in the manufacture of new generation dressings for the treatment of open wounds, combining photo-induced antimicrobial action on the surface, chemo-induced action in the core of the wound and improved healing power, as the hydrogel can absorb exudate and thus maintain a moist environment. Fine characterisation of the structures and rheological behaviour of the hydrogels will be carried out and a detailed study of the in vitro and in vivo antimicrobial activity will also be conducted on different bacterial strains and on open wound models.

The detection and quantification of water traces in liquids and relative humidity (RH) in gas are critical for many technological and industrial applications. Water photoluminescent (PL) sensors are increasingly investigated due to their high sensitivity and ability of in situ detection. However, new sustainable, reusable and recyclable sensors are highly desirable. The ALPS-Water project gathers three partners (IMN, SMS and PBS) and purposes to investigate the potentiality of new anhydrous alkali salts of the lanthanide-free polyoxometalate [SbW6O24]7- (SbW6), to reversibly scavenge and optically detect water in the air and in organic solvents. These materials are elaborated via low-energy and eco-friendly syntheses, and they exhibit high recycling potential. Upon exposure to water at room temperature, they rapidly convert to hydrates, resulting in strong PL quenching effects due to H-bonding interactions between SbW6 units and water molecules. Moreover, the anhydrous phases are regenerated by soft thermal treatments (T = 200 °C) and they robustly withstand repeatable hydration/dehydration procedures. In this series, Na7[SbW6O24] senses RH with a limit of detection (LOD) of 2.2% RH, and at least detect water traces in acetonitrile. Further investigations are necessary to streamline the reactivity of the anhydrous salts towards water that is rather complicated owing to the existence of intermediary hydrates with distinct PL responses. Thus, the project’s partners will mobilize complementary cultures, skills and resources to enrich this class of materials, to investigate phase relationships between (an)hydrated salts, and to optimize their sensing performances. The integration of alkali SbW6 salts into polymer matrices will be also investigated in order to elaborate new sensing devices with improved applicability. The first objective is to correlate chemical composition, crystal structure, and PL properties of the alkali SbW6 salts. This will be reached by performing a prospective research of new phases which will vary with the nature and the ratio of the alkali ions, and with their degree of hydration. New crystallization routes of intermediary hydrates will be developed thanks to experimental elaborations of binary and/or ternary phase diagrams between salts, water and/or anhydrous solvent. The crystal structures of the water-sensitive (an)hydrated/deuterated phases will be determined by performing advanced X-ray, neutron and electron diffraction analyses. Combined Maximum Entropy Method and DFT calculations will also allow accurately characterizing the H-bonding networks involving the SbW6 surface. The recycling procedures of salts will be also optimized. The second objective consists in streamlining the hydration/dehydration processes. Thanks to experimental techniques dedicated to the study of thermodynamic solid/vapor equilibria, i.e. gravimetric vapor sorption experiments and X-ray diffraction or microscopy under variable RH, the RH-dependent stability domains of each phase will be investigated. A kinetic study of the phase conversions will be also carried out to correlate the microstructure of solids with their hydration rates. The third objective is the characterization of the water sensing performances of the anhydrous phases as such or incorporated into polymer matrices. This will be realized by performing in situ PL experiments under variable RH in the air or water content in a wide range of organic solvents. This would allow correlating composition, crystal structure, particle size and morphology of the salts with their sensing parameters, i.e. LODs, limits of quantification (LOQs), detection ranges and detection rates. As a long-term prospect, this project may offer the great opportunity to develop new PL solids entering the exclusive inner circle of sustainable, reusable and shaped sensors able to rapidly detect (i) RH in air with LODs below 1% RH, and (ii) water traces in solvent media with LODs below 0.01% v/v.

The gold standard procedure for treatment after a severe nerve injury is to use nerve autograft but several drawbacks are raised. In recent years, advances have been made on the development of artificial nerve guides to replace the autograft, but no system has been able to consistently demonstrate adequate superiority. Moreover, in complex surgical reconstruction, the repaired nerve is sometimes hard to reach (due to a bone canal for example) or morphologically complex in the mean of multiple bifurcations (the repair of the brachial plexus for example). Recent years have seen the rise in silk-based materials as silk fibroin has been demonstrated to be a versatile natural polymer. Furthermore, silk fibroin is a natural, biocompatible, and biodegradable material that is readily chemically and biochemically. The Smart2Graph project introduces an adaptable foundation design of a more effective synthetic nerve guidance conduit for peripheral or central nerve repair. The project will be articulated around 3 main axes detailed in this proposal: (i) The synthesis and physico-chemical characterization of biodegradable silk fibroin and collagen matrices capable of being used as bio-ink. The presence throughout the polymer gel of graphene oxide and nanoparticles (especially magnetite) will be able to give specific features to these gels such as electroconduction, magnetism or electrically triggered drug release. (ii) These versatile matrices will then be tested for two potential processing techniques either additive manufacturing recreating aligned graphene sheets or self-alignment of graphene and iron oxide nanoparticles under electrical or magnetic fields. The aim is to obtain small (millimeter scale) tubes of polymers featuring guides of aligned graphene structures able to guide growing neurite fibers during nerve regeneration. (iii) The biocompatibility of these artificial nerves as well as their regenerative capacity will finally be tested in vitro in cultures of glial and neurons from the central and peripheral nervous system and later in vivo by grafting experiments in an animal model of facial nerve realized by clinicians. We are targeting two potential commercial deliverables. Firstly, we will develop 3D printed tube-like structures (mixed silk and collagen) with internal aligned graphene able to focus on the repair of complex nerve situation (bifurcation, brachial plexus,…). Secondly, we will work on injectable solutions with a self-assembling system aligning the graphene for hard to reach area (mostly bone canal, such as the alveolar inferior nerve, a branch of the facial nerve for example). The Smart2Graph project, through the quality and interactivity of its participants (with scientific, clinic and industrial partners), the technological innovation of the deliverables developed and the adequacy with the identified needs of the market, guarantees a rapid translation of the developed scientific results into innovative medical products (gel and 3D-printed scaffold) dedicated to regenerative medicine.

Post-translational modifications (PTM) are crucial to regulate cellular functions in all living organisms, on short time scales, especially in bacteria. However, little is known today about the actors involved in lysine acetylation (enzymes and modified proteins) and their role. We have generated exciting preliminary data showing that acetylation plays a crucial role in Acinetobacter baumannii pathogenesis and biofilms. Therefore, targeting the actors involved in acetylation can be a promising antibacterial strategy, as it has been shown to treat some cancers and latent viral infections. The aim of this project is to better understand the acetylation process and propose new molecules to combat biofilm formation and environmental persistence of Acinetobacter baumannii by targeting proteins involved in the addition or removal of acetylation.