Assessment of Osteogenic Differentiation Potential of Cytocompatible Rice Husk-Derived Lignin/Silica Nanohybrids for Bone Tissue Engineering

Currently, agro-industrial co-product and waste management by developing new materials have received immense attention. In this way, rice husk (RH), an inexorable co-product of rice mills, generates a considerable quantity worldwide. According to the rice husk chemical composition, it can be served as an excellent eco-friendly, a readily available, sustainable, and renewable precursor for high-value materials. Thus, we have successfully prepared lignin/silica nanohybrids (LiSNHs) using the RH as a bioprecursor through a facile approach in this present study. The RH-derived LiSNHs were characterized using an X-ray diffractometer, transmission electron microscope, and thermal gravimetric analysis. The cytocompatibility behavior of RH-derived LiSNHs was investigated using cell viability and acridine orange/ ethidium bromide staining assessment. Furthermore, we have examined the LiSNHs role on the osteogenic differentiation potential in human mesenchymal stem cells (hMSCs). TEM images of the LiSNHs display 5 - 35 nm in diameter tiny silica nanostructures conjugated on the lignin spheres with similar to 200 nm. The LiSNHs showed outstanding thermal stability in thermogravimetric analysis. The cell viability and microscopic examination indicate that LiSNHs do not cause any remarkable changes in cell viability and health. Interestingly, the LiSNHs triggers the osteogenic differentiation in hMSCs by up-regulation of BMP-2 and ALP genes expression. The overall study concludes that RH-derived LiSNHs possessed excellent cytocompatibility that enhanced osteogenic differentiation in hMSCs, an ideal for bioengineering applications. As well, the agro-industrial waste RH-derived LiSNHs is considered as a biomaterial for various biomedical applications.