Electrospun hybrid biodegradable 3D scaffold for ACL regeneration

Regenerative medicine approaches for the regeneration of the anterior cruciate ligament (ACL) injury have been study since the 1950s. On this thesis work an electrospun hybrid biodegradable 3D scaffold for ACL regeneration is studied using polycaprolactone (PCL), iron wire and silk fibroin (SF). The electrospinning process of different models of each material was optimised and models were analysed by SEM observation, tensile test characterisation, degradation test and in vitro indirect cytotoxicity test. The electrospun scaffold presented fibers independent on the amount of iron wire present, demonstrating that the presence of Fe wire allows for the formation of fibers by electrospinning on top of it. The mechanical characteristics of the scaffold were independent of the amount of iron wire but showed a tendency of exhibiting higher values for an increasing time of electrospinning. During this thesis study the biocompatibility of the electrospun PCL and the problems with toxicity of the iron wire were assessed. Finally the stability of the PCL in a physiological-like environment and the fast degradation rate of the Fe wire are presented. From the obtained results it is possible to continue the research of the design here presented since the problems that are reported, such as lower mechanical properties, higher degradation rate and cytotoxicity of the scaffold, might be solved by the coating of the iron wire with a mechanical and chemical resistant polymer. The successfully electrospinning of the silk fibroin and the production of PCL models with the iron wire support structure are highlighted as two of the most important findings of this thesis work.