High aspect ratio phospho-calcified rock candy-like cellulose nanowhiskers of wastepaper applicable in osteogenic differentiation of hMSCs.

The aim of this study was to prepare cellulose nanowhiskers (CNWs) from wastepaper powder (WPP), as an environmentally friendly approach for obtaining the source material, which is a highly available and low-cost precursor for cellulose nanomaterial processing. Acid hydrolysis and calcification treatments were employed for extraction of CNWs and preparation of novel phospho-calcified cellulose nanowhiskers (PCCNWs). CNWs and PCCNWs were analyzed through optical microscopy (OM), scanning electron microscopy (SEM), Fourier-transformed infrared spectra (FTIR) and X-ray diffraction analysis (XRD). Cell behaviors in the presence of CNWs and PCCNWs were studied by MTT assay and live-dead staining. Finally, the effect of these particles on osteogenic differentiation of stem cells was evaluated based on alkaline phosphatase activity (ALP), calcium mineralization as well as von Kossa and alizarin red staining. Based on the results, PCCNWs had a positive effect on osteogenic differentiation of human mesenchymal stem cells (hMSCs) and can be used for developing new approaches for bone tissue engineering.