Page 88 - Tailoring Electrospinning Techniques for Regenerative Medicine - Marc Simonet

CHAPTER 4
Figure 4.5 Scanning electron microscope images of the LTE spun sca olds for which their mean fiber diameter was adjusted by the selection ofthesolventsystem:(a)10%PCLinCHCl3,(b)10%PCLwith1%PFinCHCl3,(c)10%PCLwith10%PFinCHCl3,(d)10%PLAinCHCl3,(e)10 % PLA with 1 % PF in CHCl3, (f) 10 % PLA with 10 % PF in CHCl3.
For these experiments, the target size (drum length = 50 mm), solution flow rate, and polymer concentration were kept constant to ensure that the same amount of polymer was deposited. This allowed us to directly attribute di erences in sca old thickness (due to a change in fiber sti ness) at a given spinning time to an increase/decrease in void space. [Note: a thickness of ~4 mm was measured for all sca olds directly a er spinning. This is the thickness of the polymer sca olds including ice crystals].
Intriguingly, the thickness of the low-temperature electrospun sca olds considerably depended on the fiber sti ness. Final sca old thickness increased with fiber sti ness for both PCL and PLA LTE architectures (Figure 4.6). We attribute this increase in sca old thickness to an increase in void space, since the amount of material that was spun within a given spinning time was identical. In strong contrast, the final sca old thickness was a ected neither by a change in fiber sti ness (through variation of fiber diameter) nor the choice of material (PCL vs. PLA) when using conventional electrospinning methods.
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