Nano-Graphene Oxide Functionalized Bioactive Poly(lactic acid) and Poly(ε-caprolactone) Nanofibrous Scaffolds

Abstract

A versatile and convenient way to produce bioactive poly(lactic acid) (PLA) and poly(ε-caprolactone) (PCL) electrospun nanofibrous scaffolds is described. PLA and PCL are extensively used as biocompatible scaffold materials for tissue engineering. Here, biobased nano graphene oxide dots (nGO) are incorporated in PLA or PCL electrospun scaffolds during the electrospinning process aiming to enhance the mechanical properties and endorse osteo-bioactivity. nGO was found to tightly attach to the fibers through secondary interactions. It also improved the electrospinnability and fiber quality. The prepared nanofibrous scaffolds exhibited enhanced mechanical properties, increased hydrophilicity, good cytocompatibility and osteo-bioactivity. Therefore, immense potential for bone tissue engineering applications is anticipated.

Keywords: PCL; PLA; biomineralization; graphene oxide; mechanical properties; scaffold.

Figure 1

(a) TEM images of poly(lactic acid) (PLA) and PLA-nGO1 fibers; (b) Fourier transform infrared (FTIR) spectra of PLA, PLA-nGO1, PLA-nGO2.5, and PLA-nGO5 fibers.

Figure 2

SEM images and the fiber size distribution of PLA, PLA-nGO1, PLA-nGO2.5, and PLA-nGO5 fibers.

Figure 3

XRD spectra of PLA, PLA-nGO1, PLA-nGO2.5, and PLA-nGO5 fibers.

Figure 4

(a) Stress-strain curves of PLA, PLA-nGO1, PLA-nGO2.5 and PLA-nGO5 fibers; (b) SEM images of PLA, PLA-nGO1, PLA-nGO2.5, and PLA-nGO5 fibers after tensile break.

Figure 5

(a) Water contact angle measurements on PLA, PLA-nGO1, PLA-nGO2.5, and PLA-nGO5 fibers; (b) The relative cell viability of PLA, PLA-nGO1, PLA-nGO2.5, and PLA-nGO5 fibers; (c) Optical microscopy images of PLA-nGO2.5 fibers after 4 days of cell culture; (d) SEM image of PLA-nGO2.5 fibers after 4 days of cell culture.

Figure 6

SEM images of PLA, PLA-nGO1, PLA-nGO2.5, and PLA-nGO5 fibers after 11 days of mineralization in simulated body fluid (SBF) and EDS spectra of PLA-nGO5 fibers after 11 days of mineralization in SBF.

Figure 7

SEM images of PLA, PLA-nGO1, PLA-nGO2.5, and PLA-nGO5 fibers after 24 days of mineralization in SBF.

Figure 8

(a) FTIR spectra of poly(ε-caprolactone) (PCL), PCL-nGO1, PCL-nGO2.5, and PCL-nGO5 fibers; (b) XRD spectra of PCL, PCL-nGO1, PCL-nGO2.5, and PCL-nGO5 fibers; (c) SEM images of PCL, PCL-nGO1, PCL-nGO2.5, and PCL-nGO5 fibers.

Figure 9

(a) Stress–strain curves of PCL, PCL-nGO1, PCL-nGO2.5, and PCL-nGO5 fibers; (b) SEM images of PCL, PCL-nGO1, PCL-nGO2.5, and PCL-nGO5 fibers after tensile break; (c) Optical microscopy images and SEM images of PCL-nGO1 and PCL-nGO2.5 after 4 days of cell culture; (d) Water contact angle measurements on PCL, PCL-nGO1, PCL-nGO2.5, and PCL-nGO5 fibers.

Figure 10

SEM images of PCL-nGO1, PCL-nGO2.5, and PCL-nGO5 fibers after 11 and 24 days of mineralization in SBF.