The improvement of cell infiltration in an electrospun scaffold with multiple synthetic biodegradable polymers using sacrificial PEO microparticles

Electrospinning is a fabrication technique to generate three dimensional scaffolds with a fiber structure that imitates extracellular matrix for tissue engineering constructs. The versatile characteristics of the electrospinning process yields designer scaffolds made of biodegradable polymers or natural proteins with controllable fiber diameters, biodegradation, and mechanical properties. A limitation of conventional electrospun scaffolds is the dense fiber packing with low porosity that leads to poor cell infiltration. Electrospraying sacrificial polyethylene oxide (PEO) microparticles in combination with electrospun scaffolds are a method to increase porosity. We report the effectiveness of electrospraying PEO microparticles to increase porosity of the most commonly used biodegradable polymers: polyglycolic acid (PGA), poly (lactic-co-glycolic) acid (PLGA), and polycaprolactone (PCL). The biodegradable polymer electrospun scaffolds with the sacrificial PEO microparticles were found to have improved cell proliferation and infiltration with human fibroblasts compared to conventional electrospun scaffolds. The mechanical properties of the more robust PGA and PLGA had minor changes, but the more elastic PCL was observed to be weaker and less stiff after the removal of the PEO microparticles. Therefore, this study found PEO microparticles can increase porosity and cell infiltration with stable mechanical properties for a wide variety of biodegradable polymers in electrospun scaffolds.