Electrospinning Regimes for Tissue-Engineering Scaffolds: A Quantitative Synthesis of Reported Process Parameters

Abstract

Electrospinning regimes are almost always reported as an applied voltage together with a working distance, which prevents direct comparison between laboratories because the same voltage produces different field strengths at different distances. This review collects the process parameters reported in thirteen studies of electrospun scaffolds for nerve, vascular, cardiac, cartilage, intervertebral-disc and bone tissue, converts them to a common basis, and analyses their distribution. When expressed as the normalised field strength E = U/H, the reported regimes occupy a narrow band: 0.56–2.00 kV cm⁻¹ with a mean of 1.12 ± 0.44 kV cm⁻¹ and a median of 1.09 kV cm⁻¹, the interquartile range being 0.80–1.25 kV cm⁻¹. Working distances range from 10 to 25 cm (median 15 cm) and feed rates from 0.6 to 12 mL h⁻¹ (median 1.5 mL h⁻¹), the latter spanning more than an order of magnitude. Fibre diameters reported for the same tissue class vary by up to an order of magnitude, and no correlation between normalised field strength and fibre diameter is detectable across the pooled data, indicating that diameter is controlled predominantly by the solution rather than by the field. The narrowness of the field-strength band is interpreted as an empirically converged process window, and its use as a first-approximation starting point for new polymer systems is proposed, together with a minimum reporting set that would make future studies comparable.