Synthetic Polymer-based Electrospun Fibers: Biofunctionalization Strategies and Recent Advances in Tissue Engineering, Drug Delivery and Diagnostics

Background: Over the last decades, synthetic polymer-based electrospun nano/microfibers have emerged as potent materials in crucial biomedical applications such as tissue engineering, drug delivery and diagnostics. This is mainly attributed to versatility and reproducibility of the electrospinning (ES) process, as well as the high surface- to-volume ratio of the generated nanostructures. Appropriate functionalization with dedicated biomolecules (i.e. cell adhesive peptides, therapeutic molecules, bio-probes) is a critical requirement for the performances of such materials in their related application. Methods: We report on the different chemical methodologies for preparing biofunctionalized synthetic polymer fibers, on the basis of two main approaches: biomolecule introduction after ES process (post-ES) and before ES (pre-ES). We then focused on the latest implications of such materials in areas of tissue engineering, drug delivery and diagnostics. Results: This review describes the numerous immobilization strategies (either covalent or non-covalent) developed for designing biofunctionalized fibers, as well as their impact on their properties in dedicated application. The inputs of advanced conjugation tools (“clickable” chemistries, PEG linkers) for biofunctionalization are also highlighted. In the light of the literature, it appears that increasing research efforts are now devoted to multifunctional character and fiber combination with other materials (hydrogels, inorganic particles, microfluidic devices) for improved and tunable performances. Conclusion: Owing to flexibility and robustness of ES process as well as advances in conjugation and polymer/material engineering, high degree of control over biofunctionalization can now be achieved, to fit as best as possible the requirements of the targeted application. The performances reached up to now augur well for the future of such class of materials.