Development and Characterisation of Novel Coaxial Biopolymer Fibres

Implantable drug delivery systems have attracted a great deal of attention in recent years. In these applications, usually active agents (e.g., drugs, growth hormones, etc.), which are released in their environment, are loaded into a host hydrogel or polymeric fibre and thus may provide a healthy environment and enhance regeneration of the surrounding tissue. Although hydrogel structures have shown good efficiency in releasing the different types of drugs, it is worth mentioning that due to their burst release kinetics, they usually cannot be applied in controlled drug release systems. Therefore, there are many attempts to develop new structures to overcome this problem. In this work, we introduce a coaxial wet-spinning method to develop novel polycaprolactone (PCL)/alginate and PCL/chitosan coaxial fibres for future application for controlled drug delivery. A coaxial wet-spinning assembly strategy is proposed to readily prepare core-sheath fibrous structures. Fine and continuous coaxial fibres with the sheath of polycaprolactone and core of alginate or chitosan were prepared by necessary wet spinning conditions. By applying this procedure, coaxial fibres with a broad compositional range and controllable diameters were fabricated. The morphological and mechanical properties of these fibres were studied, with release profiles from the coaxial fibers determined using a model component. Our results suggest that unlimited length of designed coaxial PCL/alginate and PCL/chitosan fibres can be produced giving potential to create 3D textile structures. Moreover, these designed coaxial fibres could be potential candidates for tissue engineering with the feature of controlled drug delivery.