PLA-based scaffolds for tissue engineering structured at both the micro- and nano-scale

A still unsolved problem in tissue engineering is the absence of fast, inexpensive and effective methods for producing scaffolds presenting multiple dimensional scales, i.e. concurrently possessing well defined micro- and nano-structures, a characteristic necessary to imitate the natural extracellular matrix. In this work we show that this goal is obtaineble coupling two very simple, inexpensive and rapid fabrication techniques, namely conventional FDM 3D-printing, for generating micro-structured scaffolds, and ASB-SANS, a fast, self-assembly-based wet processing method able to induce the formation of nanostructures on the surface of the printed base scaffolds. We realized four types of cylindric, 4x4mm (diameter/height) scaffold, i.e. A) fully solid, B) fully solid with nanostructures, C) microporous and D) microporous with nanostructures. The so-fabricated scaffolds were used to grow human gingival mesenchimal cells (hGFs) at different time scales (24 hours and one week). The growth results indicated that the scaffolds of type D (microporus with nanostructures) are the most effective in promoting the hGFs vitality, delivering a 30+% increase with respect to the fully solid scaffolds (type A) at both the 24 h and one week time scales. Estimated costs for the realized scaffolds are of less than 0.5 $ per piece, and the fabrication time is about half a day per single scaffold. These data, coupled to the already promising results shown by the hGFs growth tests, suggest that the here presented double dimensional scale approach could be of much help in the field of practical tissue engineering.