Table 1.
Materials systems used for different experiments.
Fig 1.
Digital images of the slit-fixture.
(a) Close-up of the slit-surface created by the central alignment of two troughs. (b) Slit-fixture connected to a solution reservoir base. (c) Schematic of the axial cross section of the slit-fixture illustrating compartmentalization of sheath and core solutions below the slit and co-localization of the solutions at the slit exit.
Fig 2.
Overview of slit-surface electrospinning using System A.
(a) Example of multiple electrospinning cone-jets formed across a slit-surface. (b) Electrospinning jet formed from sheath solution without core solution entrainment. (c) Same electrospinning jet as in (b), demonstrating the spontaneous entrainment of core solution. (d) Fully-formed electrospinning jet exhibiting a core-sheath structure. (e) Representative scanning electron microscopy image of fibers fabricated using slit-surface electrospinning. (f) Cross-sectional image showing core-sheath fiber structure. The arrow points to a dexamethasone drug particle.
Fig 3.
Representative scanning electron images depicting different types of core-sheath fibers fabricated using slit-surface electrospinning.
(a) bicomponent (System D) (b) hollow (System E); and (c) unelectrospinnable PDMS core—PLGA sheath (System F).
Fig 4.
Video capture images depicting the morphology of core/sheath cone-jets using System A.
Experiments were conducted at a constant sheath flow rate of 200 ml/h while varying the core solution flow rate. (a, b) Distinct core/sheath cone-jets were formed when the core flow rates were set to 40 and 20 ml/h, respectively. (c) Non-distinct core/sheath cone-jets were formed when the core flow rate was set to 60 ml/h.
Fig 5.
Video capture images depicting the morphology of core/sheath cone-jets of System B.
Experiments were conducted under different solution flow rates to demonstrate control of emitted core-sheath cone-jets. The core fluid stream narrows as the ratio of total solution velocity to core solution velocity is increased. (a) vsheath:vcore = 2.0, (b) vsheath:vcore = 5.5, and (c) vsheath:vcore = 7.0. (Width of image corresponds to field of view of 17 mm).
Fig 6.
Video capture images core/sheath cone-jets using System A emitted from differing sheath slit widths.
(a, b) Distinct core/sheath cone-jets were formed at slit widths of 1.5 and 2.2 mm, respectively. (c) Non-distinct core/sheath cone-jets were formed at a slit width of 3.0 mm.
Fig 7.
Video capture images of emitted core/sheath cone-jets using System C, whereby different sheath solution viscosities were employed.
(a) Distinct core/sheath cone-jets were formed when the sheath solution viscosity was greater than the core solution viscosity. (b) Non-distinct core/sheath cone-jets were formed when the sheath solution viscosity was less than the core solution viscosity.