The platform is built by inkjet-printing graphene oxide/growth-factor precursor inks onto electrospun poly(lactide-co-ε-caprolactone) (PLCL) fiber membranes, followed by reduction with ascorbic acid to form rGO/growth-factor micropatterns. The team screened printing-layer number, nozzle configuration, and electric-field strength, using band-width fidelity, continuity, overspray, and apparent conductivity combined with neural-cell readouts as evaluation metrics. A 4-layer double-nozzle condition produced a core printed-band width of 204.8 µm, close to the designed 200 µm, with 94.5% continuity and 0.50% overspray, while providing an apparent conductivity of 0.432 ± 0.038 S/cm, approximately 78.8% of the 10-layer condition.
In PC-12 cultures, 150 mV/cm direct-current stimulation was associated with greater βIII-tubulin-positive neurite-like outgrowth and alignment than without stimulation or at 300 mV/cm, reaching 19,060 ± 2,417 µm total neurite length per field at day 21. Dorsal root ganglion neurons extended aligned TUJ1-positive neurites along the printed tracks, and S16 Schwann cells expanded on neuregulin-1/rGO-patterned substrates under the same stimulation condition. RT-qPCR and western blotting showed higher levels of neuronal regeneration-associated and Schwann-cell-associated markers under 150 mV/cm than under unstimulated or higher-field conditions. The team suggests the platform can be used to evaluate printing parameters and defined topographical, electrical, and biochemical cues within tested neural cell models in vitro.