Figure modified from Almería et al. [16] to illustrate polydispersity of PLGA ES particles as a function of liquid flowrate (Q (μl/h)) and polymer volume fraction at the Rayleigh limit (ϕ). The Rayleigh limit is the point at which the electric stress and surface tension become unbalanced and the Taylor cone, or the flow in general, becomes unstable. Entanglement volume fraction, ϕent, is the volume fraction of polymer within the droplet that is large enough to form an entangled network of polymer chains. The overlap volume fraction, ϕch.ov, is the polymer volume fraction where the average distance between chains is equivalent to their radius in solution.