Hydroxyapatite nanoparticles derived from mussel shells for in vitro cytotoxicity test and cell viability

Hydroxyapatite (HA) nanoparticles derived from mussel shells were prepared using the wet precipitation method and were tested on human mesenchymal and epithelial cells. Shells and HA powder were characterized via X-ray diffraction analysis (XRD) and scanning electron microscopy along with energy dispersive X-ray spectroscopy (SEM/EDX), high resolution transmission electron microscopy (HR-TEM) and Fourier transform infrared spectroscopy (FTIR). The in vitro cytotoxic properties of HA and mussel shells were determined using sulphorhodamine B (SRB) assays for MCF-7 cells (HepG2) and colon (Caco-2) cells. Cell viability tests confirmed the nontoxic effects of synthesized HA and mussel shells on human mesenchymal stem cells (h-MSCs) and epithelial cells. Toxicity values were less than 50% of the cell's validity ratio based on analyses using different concentrations (from 0.01 to 1,000 μg). The results indicate that MSC and epithelial cell attachment and proliferation in the presence of both HA and shell occurred. The proliferation capability was established after 3 and 7 days. SEM images revealed that stem cells and epithelial cells attached to the scaffold indicated full and complete integration between the cells and the material. It seems that due to the ion exchange between bovine serum albumin solutions (BSA) and HA, the FTIR data confirmed an increase in the amide I and amide II bands, which indicates the compatibility of the BSA helix structure. This study sheds light on the importance of merging stem cells and nanomaterials that may lead to improvements in tissue engineering to develop novel treatments for various diseases.