Stereolithography 3D printing of microgroove master moulds for topography-induced nerve guidance conduits

Patients who have peripheral nerve damage from trauma or disease may suffer lifelong disability. Current interventions such as nerve allografts are inadequate due to limited availability of tissue and donor-site morbidity. Commercial nerve guidance conduits are used to bridge the damaged nerve gap and restore function. Typically, however, they lack cell-instructive guidance cues to promote directed regeneration. Tissue-engineered nerve guidance conduits that utilise micro- and nano-topographical architectures have been demonstrated to direct cell behaviour and contact guidance. This study uses projection micro-stereolithography-based three-dimensional (3D) printing to fabricate microgrooved (10–30 μm) master moulds to produce polydimethylsiloxane (PDMS) moulds and solvent cast polycaprolactone and polylactic acid films. The polymer microgrooves were successfully fabricated and were able to be formed into tubular nerve guidance conduits. The surface morphology, roughness, wettability, and thermal properties of the films were characterised. The microgroove topography improved proliferation and induced alignment of SH-SY5Y cells. This facile 3D printing approach is promising for the fabrication of nerve guidance conduits with topographical guidance cues as it obviates the need for using photolithographic techniques. Thus, this approach provides an alternative that is simpler, faster, cheaper, and offers greater design freedom.