Electrospinning of PLA Nanofibers for Coronary Stents: Influence of Solution Properties and Process Parameters

ABSTRACT Electrospinning has been studied to deposit polylactic acid (PLA) nanofibers on complex coronary stent geometries. The rheological properties of PLA with two molecular weights were analyzed in various solvents, including chloroform, acetone, dichloromethane, and dimethylformamide, to determine the entanglement concentration. High molecular weight PLA dissolved in a 2:1 v/v chloroform: acetone was suitable to form bead‐free nanofibers with uniform morphology. A response surface methodology was implemented to evaluate electrospinning parameters (concentration, flow rate, and voltage). The thin film mat was examined by scanning electron microscopy (SEM) to determine the size of the fibers and the fiber diameter distribution. A concentration of 8% w/v, a voltage of 15 kV, and a flow rate of 0.02 mL/min produced bead‐free nanofibers with an average diameter of around 491 ± 150 nm on a flat surface. Additionally, a PLA thin film of nanofibers was deposited on a coronary stent geometry using a rotary motor, resulting in a bead‐free uniform film with fibers measuring approximately 817 ± 388 nm.