Chiang Mai Journal of Science

     Bone and joint tuberculosis is one of extrapulmonary tuberculosis that is commonly found globally. Treatment of bone tuberculosis typically involves long term oral medication and frequently causes side effects due to its systemic administration route. In order to mitigate the side effects and to increase the performance, the use of localized medication for sustained drug release was investigated. Three first-line anti-tuberculosis drugs were loaded into three-dimensional printed hydroxyapatite (3DP HA) by vacuum infiltration and then further infiltrated by low molecular weight polycaprolactone (PCL). It was observed that PCL uniformly coated on the surface and filled the inside pores of all infiltrated samples and did not much affect the drug loading content in the samples. Rifampicin (RIF) loaded samples, either non-infiltrated or infiltrated ones, displayed longer sustained release than those of isoniazid (INH) or pyrazinamide (PZA) loaded samples, but the release of infiltrated samples could be further enhanced in terms of released content and duration. These were related to the drug solubility and diffusion distance of drugs in the samples. Bioactivity of the drug-loaded samples was also not hampered as the apatite layer was seen to grow on the surface ascertaining its role as a dual functioned bone graft.