Easy fabrication of aligned PLLA nanofibers-based 2D scaffolds suitable for cell contact guidance studies

An easy, low-cost and fast wet processing-based method named ASB-SANS (Auxiliary Solvent-Based Sublimation-Aided NanoStructuring) has been used to fabricate poly(L-lactic acid) (PLLA) highly ordered and hierarchically organized 2D fibrillar patterns,with fiber widths between 40 and 500 nmand lengths exceeding tens of microns. A clear contact guidance effect of these nanofibrillar scaffolds with respect to HeLa and NIH-3T3 cells growth has been observed, on top of an overall good viability. For NIH-3T3 pronounced elongation of the cells was observed, as well as a remarkable ability of the patterns to guide the extension of pseudopodia. Moreover, SEM imaging revealed filopodia stemming from both sides of the pseudopodia and aligned with the secondary PLLA nanofibrous structures created by the ASB-SANS procedure. These results validate ASB-SANS as a technique capable to provide biocompatible 2D nanofibrillar patterns suitable for studying phenomena of contact guidance (and,more in general, the behavior of cells onto nanofibrous scaffolds), at very lowcosts and in an extremely easy way, accessible to virtually any laboratory.