Investigation of process parameters of electrohydro-dynamic jetting for 3D printed PCL fibrous scaffolds with complex geometries

Tissue engineering is a promising technology in the field of regenerative medicine with its potential to create tissues de novo. Though there has been a good progress in this field so far, there still exists the challenge of providing a 3D micro-architecture to the artificial tissue construct, to mimic the native cell or tissue environment. Both 3D printing and 3D bioprinting are looked upon as an excellent solution due to their capabilities of mimicking the native tissue architecture layer-by-layer with high precision and appreciable resolution. Electrohydrodynamic jetting (E-jetting) is one type of 3D printing, in which, a high electric voltage is applied between the extruding nozzle and the substrate in order to print highly controlled fibres. In this study, an E-jetting system was developed in-house for the purpose of 3D printing of fibrous scaffolds. The effect of various E-jetting parameters, namely the supply voltage, solution concentra-tion, nozzle-to-substrate distance, stage (printing) speed and solution dispensing feed rate on the diameter of printed fibres were studied at the first stage. Optimized parameters were then used to print Polycaprolactone (PCL) scaffolds of highly complex geometries, i.e., semi-lunar and spiral geometries, with the aim of demonstrating the flexibility and ca-pability of the system to fabricate complex geometry scaffolds and biomimic the complex 3D micro-architecture of na-tive tissue environment. The spiral geometry is expected to result in better cell migration during cell culture and tissue maturation.