Nanotechnology 34 (2023) 485701

Karima Belabbes, Matthieu Simon, Christopher Yusef Leon-Valdivieso, Mathilde Massonié, Audrey Bethry, Gilles Subra, Xavier Garric and Coline Pinese

 ABSTRACT

The design of a biomimetic scaffold is a major challenge in tissue engineering to promote tissue reconstruction. The use of synthetic polymer nano fi bers is widely described as they provide biocompatible matrices whose topography mimics natural extracellular matrix ( ECM ) . To closely match the biochemical composition of the ECM, bioactive molecules such as gelatin are added to the nano fi bers to enhance cell adhesion and proliferation. To overcome the rapid solubilization of gelatin in biological fl uids and to allow a lasting biological effect, the covalent crosslinking of this macromolecule in the network is crucial. The sol – gel route offers the possibility of gentle crosslinking during shaping but is rarely combined with electrospinning. In this study, we present the creation of Poly ( lactic acid )/ Gelatin hybrid nano fi bers by sol – gel route during electrospinning. To enable sol – gel crosslinking, we synthesized star-shaped PLA and functionalized it with silane groups; then we functionalized gelatin with the same groups for their subsequent reaction with the polymer and thus the creation of the hybrid nanonetwork. We evaluated the impact of the presence of gelatin in Poly ( lactic acid )/ Gelatin hybrid nano fi bers at different percentages on the mechanical properties, nanonetwork crosslinking, degradation and biological properties of the hybrid nano fi bers. The addition of gelatin modulated nanonetwork crosslinking that impacted the stiffness of the nano fi bers, resulting in softer materials for the cells. Moreover, these hybrid nano fi bers also showed a signi fi cant improvement in fi broblast proliferation and present a degradation rate suitable for tissue reconstruction. Finally, the bioactive hybrid nano fi bers possess versatile properties, interesting for various potential applications in tissue reconstruction.

Keywords: silylated star PLA, silylated gelatin, hybrid 3D network, bioactive scaffolds, tissue reconstruction

BIOMATERIALS SCIENCE 2022,10, 1776-1786

Hadda, Zebiri, Van Den Berghe Helene, Paunet Tom, Wolf-Mandroux Aurelie, Bethry Audrey, Taillades Hubert, Yohan Jean Noel, Yohan Jean Noël, Nelly Pirot, Botteron Catherine, Chammas Michel, Chammas Pierre-Emmanuel and Garric Xavier

 ABSTRACT

Peritendinous adhesions are complications known to occur up to 6 weeks after surgery and cause chronic pain and disability. Anti-adhesion barriers are currently the best option for prevention. In a previous study, we designed two biodegradable membranes, D-PACO1 and D-PACO2, based on new triblock copolymers and conducted in vitro evaluations. The membranes maintained filmogenic integrity, had degradation rates that promoted anti-adhesion and were biocompatible, suggesting their safe and effective use as anti-adhesion devices. To test this hypothesis, we conducted a preliminary in vivo study in a rat model of peritendinous adhesions and evaluated the membranes’ degradation rates, tendon healing and anti-adhesion effect compared to non-surgical and surgical control groups 2 and 10 weeks after surgery. Macroscopic evaluation showed membranes were effective in reducing the extent and severity of adhesions. Membranes acted as physical barriers at 2 weeks and underwent a complete or significant biodegradation at 10 weeks. D-PACO2 had a longer degradation rate compared to D-PACO1, was more effective in reducing adhesions and is expected to be more effective in promoting tendon healing. The tendency of D-PACO1 to promote tendon healing while D-PACO2 did not interfere with healing highlights the need to redesign the porosity of the D-PACO membranes for optimal nutrient diffusion, while maintaining their anti-adhesion effect and clinical usability. Preliminary findings revealed that adhesions form beyond the 6 weeks cited in the literature. In this study, adhesion formation continued for up to 10 weeks, underlining the need to increase the experimental period and sample size of future experiments evaluating anti-adhesion membranes.

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY 2022

Saxer, S.; Erdogan, O.; Paniagua, C.; Chavanieu, A.; Garric, X.; Darcos, V.

 ABSTRACT

Protein-polymer bioconjugates have shown great promise in biomedical and life science applications including drug delivery and diagnosis. The current bioconjugation strategies suffer from lack of efficiency and versatility. In this article, poly(styrene-alt-maleic anhydride) copolymers were first prepared by RAFT polymerization and characterized by different analytical techniques. Then, the poly(styrene-alt-maleic anhydride) precursors were functionalized with primary amine such as azidopropylamine and amino poly(ethylene glycol). The reaction of amino compounds with maleic anhydride was found to be a highly efficient, a versatile, and a facile chemical ligation reaction for the synthesis of macromolecules with quantitative yield under mild conditions. The main benefit is the incorporation of a wide range of functionality by easily changing the primary amine compound. For the amphiphilic graft copolymers based on poly(ethylene glycol), aggregation behavior in water was investigated. In a second part, azido-functionalized polystyrene copolymers were used to prepare a new protein-polymer bioconjugate by copper-free click chemistry reaction.