Fabrication of PLLA scaffold with gradient macro/micro/nano structure by electrophoretic deposition of carbon nanotube

• PLLA tissue engineering scaffold with gradient structure was fabricated.
• The gradient macro/micro/nano structure would mimic the natural tissue.
• Carbon nanotube coating was obtained by electrophoretic deposition method.
• The mechanism of electrophoretic deposition was discussed.

Natural tissues exhibit gradients across a spatial volume. To mimic such a gradient of natural tissue, poly (l-lactic acid) (PLLA) scaffolds with a functionally gradient structure (covered all macro, micro and nanoscale) was designed and fabricated by a thermally induced phase separation method combining electrophoretic deposition of carbon nanotube. The gradient structure was investigated by scanning electron microscope (SEM). The nanocomposite scaffolds after CNT coating still remain interconnectivity as high as the control PLLA scaffolds. The gradient scales from macro-scale (250–425 µm), subcellular scale structures (0.1–10 µm) to nanostructures (20–100 nm) in the scaffold are favor to control cellular environment and cell–matrix interactions.