Albumin-induced exfoliation of molybdenum disulfide nanosheets incorporated polycaprolactone/zein composite nanofibers for bone tissue regeneration

The two-dimensional (2D) nanomaterial incorporated polymeric matrix is being widely used as a promising reinforcement material for next-generation bone tissue engineering application. In this study, the albumin-induced exfoliated 2D MoS2 nanosheets were incorporated into polycaprolactone (PCL)/zein (PZ) composite polymeric network via electrospinning technique, and the PCL/zein/MoS2 (PZM) composite nanofibrous scaffolds were fabricated. The incorporation of different concentrations of MoS2 into PZ composite was evaluated by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis/differential scanning calorimetry (TGA/DSC), mechanical strength (in dry and wet state), and contact angle test. Moreover, the in vitro biocompatibility, cell attachment, and proliferation behavior of the composite scaffolds were evaluated on preosteoblasts (MC3T3-E1) cell lines as a model. In addition, biomineral crystal deposition was determined via simulated body fluid (SBF) incubation and Alizarin Red S (ARS) assay. The results showed that the PZM composite nanofibrous scaffold exhibited improved fiber morphology and increased wettability, compared to the PZ. Furthermore, the PZM-0.02 composite nanofibrous scaffold showed improved Young's modulus for both dry and wet state compared to other scaffolds. The in vitro biocompatibility and alkaline phosphatase (ALP) assay showed better cell attachment, proliferation and differentiation on the PZM scaffold over the PZ only. In addition, the in vitro SBF biomineralization and ARS test showed improved calcium-phosphate deposition on the PZM composite scaffold. The overall results suggest that the albumin-induced exfoliated MoS2 nanosheets incorporated PZ polymeric nanofibrous scaffold may be a potential biomaterial for bone tissue engineering application.