Fig. 3.

Poly(ε-caprolactone) (PCL) sublayers. a Macroscopic inspection of PCL fibres at 21° angle co-deposited in both orientations (+/−21°). b, c, e, f Optical microscopy of fibres obtained after one cycle of PCL fibre deposition using individual orientations. b, c Single cycle of PCL fibre deposition at +/−21° angle using a clockwise (+21°) and an anti-clockwise (−21°) rod rotation, respectively. d Mascroscopic inspection of PCL fibres at 67° angle co-deposited in both orientations (+/−67°). e, f Single cycle of PCL fibre deposition at +/−67° angle using a clockwise (+67°) and anti-clockwise (+/−67°) rod rotation, respectively. g, h Stress–strain curves for longitudinal tensile testing conducted on PCL sublayers fabricated at deposition angles of +/−21° and +/−67°, respectively. PCL sublayers were manufactured using different number of cycles of intercalated PCL fibres deposited at opposite angles (+/−). Every fibre deposition cycle using a clockwise rotational direction is alternated with a second fibre deposition cycle using an anti-clockwise rotational direction (+/−); therefore, two cycles constitute one PCL fibre sublayer (see Fig. 1). Dotted lines correspond to average stress–strain curves for longitudinal tensile tested human coronary media layers (g) and human coronary adventitia layer (h). Human coronary control data were collected from previous studies¹¹. Three experiments were conducted for each condition and the averaged curves displayed in the plot