Engineering microscale-nanoscale surfaces to selectively support eukaryotic cell survival and colonization

Recently, scientists have been investigating novel materials and techniques for growing orthopedic tissue engineering needs. Due to problems (such as infection and long healing time) that titanium-based implants cause in vivo, new polymeric materials have been introduced. In this study, poly(ε-caprolactone) (PCL) micron fibrous scaffolds were fabricated using three different concentrations (8%, 12%, and 17%) of PCL dissolved in 1,1,1,3,3,3-Hexafluoro-2-propanol via several fabrication methods specifically electrospinning, rotary-jet spinning, and airbrush. Mechanical, biological, and morphological properties were determined. Most importantly, results showed that without the use of any antibiotics, by changing the fabrication method alone and the size of the fibers, antimicrobial properties were improved without sacrificing mechanical properties and osteoblast functions. Specifically, it was found that the antimicrobial properties were improved when using airbrushing compared to electrospun and rotary-jet spun scaffolds where up to a 50% decrease in bacterial density was observed. Moreover, between all of the PCL concentrations tested, 12% PCL scaffolds possessed the least bacterial density. It was found that osteoblast adhesion and proliferation were similar for all fabrication methods; however, osteoblast differentiation was higher on the electrospun and Rotary-jet spun PCL scaffolds after 7 and 14 days, respectively. 12% PCL possessed the best mechanical properties for orthopedic applications. Thus, based on the results, 12% PCL airbrushed scaffolds show the highest Young's modulus and the optimum antimicrobial properties. In general, 12% airbrushed PCL scaffolds are recommended since they cause the least probability of infection in the body and can support the tissue in regard to strength.