Electrospun matrices for localized drug delivery: Current technologies and selected biomedical applications

Electrospinning is a versatile technique to produce scaffolds with random or alligned fiber orientation and in various shapes. Such non-wovens can serve as multifunctional matrices for tissue engineering as well as drug delivery systems. Electrospinning allows for the preparation of unique matrices with nano- to micrometer sized fibers using diverse materials and numerous fabrication techniques. A variety of post-spinning modification techniques add to the large repertoire and enable development of tailored drug delivery systems. Herein we provide an overview on current developments regarding different techniques to manufacture electrospun matrices and achieve efficient drug loading and release. The delivery systems discussed employ a broad range of drugs from small molecules like antibiotics to protein drugs such as growth factors as well as nucleic acids for gene delivery or mRNA knockdown. We further highlight various biomedical applications, where the combined features of fibrous electrospun matrices and drug delivery function have resulted in first valuable results or seem to bear interesting prospects. In summary, electrospun scaffolds are highly versatile systems for the incorporation of various drugs and allow for significant variation with regard to scaffold material, spatial design, and surface modification. However, the multiplicity of options and parameters to vary during development of electrospun scaffold based drug delivery systems may also have contributed to the small number of the concepts that were successfully translated into therapeutic reality.