In vitro study of Nano Hydroxyapatite/Streptomycin -Gelatin-Based Injectable Bone Substitute Associated- 3D printed Bone Scaffold for Spinal Tuberculosis Case

According to WHO (2018) Indonesia was placed in the third ranked of the highest number of TB sufferers worldwide. TB was caused by the Mycobacterium tuberculosis. This bacterial infection not only could affect the lungs, but also bone tissue, especially the spine, which then called as spinal tuberculosis. There had been many alternatives to overcome this case. One of them was by using Injectable Bone Substitutes (IBS) based on nano Hydroxyapatite (nanoHA), gelatin and streptomycin. The severe sponal tuberculosis case might cause the bone defect. Due to this bone defect, IBS alone would not be able to handle this issue. Thus, scaffold was needed to replace and support the infected bone. Besides, the combination between IBS paste and bone scaffold could help the bone tissue regeneration. The nanoHA and gelatin contents of the IBS paste provided the mineral which was need for bone tissue regeneration. While the bone scaffold would support those contents by providing the extracellular matrix for the new bone tissue attachment. The IBS associated- scaffold could be an alternative to deliver spinal tuberculosis' drug locally. This study aimed to evaluate the performance of this combination through antibacterial study and drug release test using UVVis spectrophotometer. As well as the cytotoxicity test to know the risk of these two materials within the body. The IBS was synthesized by mixing nano hydroxyapatite and 20 w/v% gelatin with ratio of 65:35 and 10% streptomycin addition as antibiotic agent. The mixture was added by hydroxypropyl methylcellulose as suspending agent. FTIR test showed that there was a chemical reaction occurred in the mixture. The performance of this combination showed that the released- streptomycin, qualitatively, could kill the Staphylococcus aureus trough the antibacterial test. Furthermore, it also had been proven that the IBS associated- scaffold could release an increasing streptomycin concentration over time. In addition, the combination showed a good result in cytotoxicity test where the cell viability was more than 50%. According to the results mentioned before, the IBS paste associated- scaffold was a promising breakthrough to overcome spinal tuberculosis case as a local drug deliver.