9. Store the sample in dark and acquire images using a confocal
microscope within 3 days. Figure 4f shows the immunostaining
of EA.hy926 cells on a single gelatin fiber.
4 Notes
1. To ensure a steady flow, remove any air bubbles in the syringe.
This can be done by withdrawing the piston to the volume
limit, and then slowly pushing the piston back to the position
where the solution fills the syringe. After the metallic tip is
attached to the syringe, push the piston until a droplet of the
solution is visible at the end of the tip. Remove the droplet
using tissue paper.
2. The stage should be lowered. This is to ensure a safety gap
between the stage and the metallic tip to avoid contact. Poking
the stage with the metallic tip can damage the precision of the
stage movement.
3. The selection of the initiator depends on the electrical conductivity of the polymer solution. Generally, both conductive (silicon wafer) and insulating initiators (glass slides) can be used for
solutions with high conductivities, such as PEO-water and
gelatin solutions. However, the applied voltage needs to be
sufficiently low when conductive initiators are used, in order
to avoid electric shorting of the system. Hence insulating
initiators are recommended. For solutions with low conductivities, such as PS-DMF solutions, conductive initiators are
needed. The polymer solutions and their conductivities are
listed in Table 1.
4. Ensure the two initiators are at the same height and are at least
1 mm higher than the collecting substrate. If the collecting
substrate is higher than the initiators, solution droplets will be
dispensed onto the substrate. If the initiators are at different
heights, the solution droplets will not be effectively initiated
and the fiber patterning will be hindered.
5. Always set the stage into motion before applying the voltage.
This is to avoid short-circuiting, which can cause damage to the
voltage supplier and fire hazard.
6. There are three factors contributing to the morphology of
patterned fibers: intrinsic polymer solution properties, extrinsic
operating parameters, and ambient factors. The intrinsic polymer solution properties include the parameters which reflect
the polymer entanglement. The most important parameter is
viscosity, which is listed in Table 1 for the solutions processed
using LEP. A high viscosity is essential to obtain continuous
and uniformly straight fiber patterns. Insufficient viscosity may
Low Voltage Electrospinning Patterning
133
microscope within 3 days. Figure 4f shows the immunostaining
of EA.hy926 cells on a single gelatin fiber.
4 Notes
1. To ensure a steady flow, remove any air bubbles in the syringe.
This can be done by withdrawing the piston to the volume
limit, and then slowly pushing the piston back to the position
where the solution fills the syringe. After the metallic tip is
attached to the syringe, push the piston until a droplet of the
solution is visible at the end of the tip. Remove the droplet
using tissue paper.
2. The stage should be lowered. This is to ensure a safety gap
between the stage and the metallic tip to avoid contact. Poking
the stage with the metallic tip can damage the precision of the
stage movement.
3. The selection of the initiator depends on the electrical conductivity of the polymer solution. Generally, both conductive (silicon wafer) and insulating initiators (glass slides) can be used for
solutions with high conductivities, such as PEO-water and
gelatin solutions. However, the applied voltage needs to be
sufficiently low when conductive initiators are used, in order
to avoid electric shorting of the system. Hence insulating
initiators are recommended. For solutions with low conductivities, such as PS-DMF solutions, conductive initiators are
needed. The polymer solutions and their conductivities are
listed in Table 1.
4. Ensure the two initiators are at the same height and are at least
1 mm higher than the collecting substrate. If the collecting
substrate is higher than the initiators, solution droplets will be
dispensed onto the substrate. If the initiators are at different
heights, the solution droplets will not be effectively initiated
and the fiber patterning will be hindered.
5. Always set the stage into motion before applying the voltage.
This is to avoid short-circuiting, which can cause damage to the
voltage supplier and fire hazard.
6. There are three factors contributing to the morphology of
patterned fibers: intrinsic polymer solution properties, extrinsic
operating parameters, and ambient factors. The intrinsic polymer solution properties include the parameters which reflect
the polymer entanglement. The most important parameter is
viscosity, which is listed in Table 1 for the solutions processed
using LEP. A high viscosity is essential to obtain continuous
and uniformly straight fiber patterns. Insufficient viscosity may
Low Voltage Electrospinning Patterning
133