Development of hybrid bioactive nano ﬁbers composed of star Poly (lactic acid ) and gelatin by sol – gel crosslinking during the electrospinning process
Karima Belabbes, Matthieu Simon, Christopher Yusef Leon-Valdivieso, Mathilde Massonié, Audrey Bethry, Gilles Subra, Xavier Garric and Coline Pinese
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