An efficient new method for electrospinning chitosan and heparin for the preparation of pro-angiogenic nanofibrous membranes for wound healing applications

Chronic skin wounds and surgical sutures need critical care and fast recovery, robust connection of blood vessels and effective restoration of circulation is necessary in progressive wound healing. Heparin is well known for its' anticoagulant properties, VEGF activation and antithrombosis action. Chitosan aid in the development of the vascular grafts due to its ECM like properties of blood vessels. For electrospinning of Heparin negatively charged and low molecular weight positively charges chitosan, the homogenous solution is required, they precipitate out during mixing due to opposite charges. In the current study, a an efficient strategy is developed for the electrospinning of chitosan and heparin in the presence of lysozyme. The insolubility/non-homogenous solution formation for electrospinning from charged chitosan and heparin fast acting was solved by using a small amount of N-cetyl-N,N,N-trimethyl ammonium bromide (CTAB) and the resulting solution produced very smooth nanofibers. Polycaprolactone (PCL) was found to be a suitable polymer for the electrospinning of chitosan and heparin using organic and inorganic solvents. Surface morphology of the synthesized fibers was investigated by scanning electron microscopy (SEM) and the presence of functional groups was investigated by FTIR. Degradation studies were performed which revealed that lysozyme loaded materials were degraded much faster as compared to other materials. The angiogenic and biocompatible potential of heparin with 1 mg/ml and 4 mg/ml lysozyme concentration was demonstrated by chorionic allantoic membrane (CAM) assay and it was estimated that 1 mg/ml (lysozyme) loaded CS/HA material was found to be an efficient biomaterial to stimulate angiogenesis.