 The effective temperature on the isolation and characterization of hydroxyapatite, HAP, from tuna bone was evaluated at different temperatures ranging from 200 degrees celsius to 1200 degrees celsius. The calcined bones were then characterized using thermogravimetric analysis, TG, Fourier transform infrared spectroscopy, FTIR, X-ray diffraction, XRD, field emission scanning electron microscopy, FESEM, energy dispersive X-ray spectroscopy, EDX, and cytotoxicity assays. The FTIR and TGA results revealed the presence of both inorganic and organic matrices in raw bone and a preserved carbonated group in the derived HAP. The XRD results of the derived HAP were consistent with the Joint Committee on Powder Diffraction Standards, JCPDS 09-0432 1996 data. Additionally, FESEM results showed the formation of nanostructured HAP 80-300 nanometers at 600 degrees celsius and crystalline agglomerations were observed with. This article was authored by Jaya Chandran Venkatesan and Se Kwan Kim. We are article.tv, links in the description below.