ساخت و مشخصه يابي پوشش¬هاي نانوكامپوزيتي سراميك-پليمري حاوي نانوذرات اكسيد روي و داروي دوكسوروبيسين بر داربست Ti6Al4V ساخته شده به روش ساخت افزايشي براي كاربردهاي سرطان استخوان

Drug-loaded implants can play an important role in the targeted treatment of bone cancer, especially when removing malignant tumors. The aim of this study was to fabricate an‎d characterize a bilayer calcium-phosphate coating containing zinc oxide/doxorubicin nanoparticles in a chitosan polymer matrix for targeted drug delivery an‎d reduced side effects by maintaining local drug release in the vicinity of the tumor. In this regard, first, a calcium-phosphate coating containing zinc oxide nanoparticles was applied to a porous Ti6Al4V scaffold fabricated by additive manufacturing method at two different porosity levels by plasma electrolytic oxidation (PEO). The coatings were characterized using X-ray diffraction pattern, scanning electron microscopy, contact angle, potentiodynamic polarization test, an‎d electrochemical impedance spectroscopy. Also, the bioactivity an‎d interaction of MG-63 cells with the coating were eva‎luated. The results showed that the coating thickness on the smaller porosity sample was approximately 1.8 times that on the larger porosity sample. The zinc oxide nanoparticles were uniformly dispersed in the coating, leading to a decrease in the hydro‎philic behavior of the coatings. In addition, both types of samples, by strengthening the barrier layer, improved the long-term corrosion behavior of the substrate, with a more prominent effect on the smaller porosity samples. In addition, after 14 days of immersion in the simulated body solution, no degradation of the coating was observed, an‎d cauliflower-shaped hydroxyapatite precipitates were distributed throughout the surface. MG-63 cells on the smaller porosity sample showed better proliferation an‎d morphology, an‎d their viability increased from 83.3 ± 1.4 (% control) in the uncoated sample to 94.9 ± 1.1 (% control). In the next step, the chitosan polymer coating containing doxorubicin was applied by immersion method an‎d eva‎luated using similar analyses an‎d infrared spectroscopy. The results showed that this layer sat well on the underlying coating an‎d concentrated in the surface depressions, improving the hydro‎philicity of the surface. Drug release study showed that the total amount of drug loaded in the sample with smaller porosity was higher than the other sample due to the presence of a larger specific surface area, approximately 0.13 mg. Also, the drug released after 6 days at neutral pH was 67%, which increased with increasing pore size an‎d decreasing pH. The viability of MG-63 cells for this sample decreased to 26.9 ± 1.1 (% control), indicating the high effectiveness of doxorubicin in inducing senescence an‎d death of cancer cells. Therefore, according to the characterizations performed, the sample with smaller porosity is an optimal sample for orthopedic applications after bone tumor removal.

مسعود عطاپور , ابوذر طاهري زاده

فاطمه داور , عبدالله صبوري , مريم رحمتي

رحمت اله عمادي , شيدا لباف , انوشه زرگر خرازي