Increasing electrospun scaffold pore size with tailored collectors for improved cell penetration

This study investigates the use of patterned collectors to increase the pore size of electrospun scaffolds for enhanced cell infiltration. The morphology of the patterned scaffolds was investigated by scanning electron microscopy, which showed that the collector pattern was accurately mimicked by the electrospun fibres. We observed an enlargement in the pore size and in the pore size distribution compared with conventional electrospinning. Mechanical testing revealed that the mechanical properties could be tailored, to some extent, according to the patterning and that the patterned scaffolds were softer than standard electrospun scaffolds. When NIH 3T3 fibroblasts were seeded onto patterned collectors improved cell infiltration was observed. Cells were able to penetrate up to 250 μm into the scaffolds, compared with 30 μm for the standard scaffolds. This increase in the depth of infiltration occurred as early as 24 h post-seeding and remained constant over 7 days.