Additive batch electrospinning patterning of tethered gelatin hydrogel fibres with swelling-induced fibre curling

Abstract

Limited methods exist to integrate patterning of free-spanning hydrogel microfibres as part of an additive manufacturing strategy. We demonstrate 3D additive batch electrospinning (3D-abES) workflow to efficiently produce layered hydrogel gelatin microfibres, tethered to 3D printed thermoplastic structures of various shapes. Enabled by the digital-design approach, multiple 3D printed fibre devices can be fabricated in a batch efficiently with minimised sample-to-sample variance. Customised fibre patterns and device geometries can be rapidly altered to fit with potential applications in 6- to 24- well plate formats. The diameter of as-produced dry fibres is in a range of ∼2−4 μm. With the intended device applications in aqueous environments, we investigate the effect of combinations of processing parameters on the gelatin fibre integrity, and its swelling behaviour when immersed in water. Aided by the parametric study, patterns of swelling-induced fibre curling, from straight to wavy, can be tuned. Our findings could serve as a guide to optimise the 3D fabrication and patterning of electrospun hydrogel-like fibres made of crosslinked hydrophilic polymers and oligomers, for cell culture or bio-sensing applications.