Figure 4:

The use of auxiliary electrodes to improve fiber alignment and control over orientation during various electrospinning methods. A) Auxiliary copper ring setup and micrographs depicting a reduction in the bending instability. Reprinted with permission from Deitzel et al.⁸⁴ Copyright 2001, Elsevier. B) Use of auxiliary electrodes to increase the degree of alignment in the circumferential direction of a rotating mandrel. Reprinted with permission from Arras et al.⁴⁹ Copyright 2012, National Institute for Materials Science. C) Auxiliary electrodes parallel to a rotating collector to induce alignment perpendicular to the direction of rotation. Reprinted with permission from Arras et al.⁴⁹ Copyright 2012, National Institute for Materials Science. D) Knife-edge bar electrodes behind the collector to focus the electric field and improve alignment. Reprinted with permission from Teo et al.⁸⁹ Copyright 2005, IOP Publishing. E) Controlled orientation of aligned fibers through rotation of the auxiliary electrodes around the needle axis. Reprinted with permission from Grasl et al.⁹⁰ Copyright 2013, American Institute of Physics.