Effect of zinc doped hydroxyapatite nanoparticles on radiosensitivity of cancer cells

In this study, zinc doped hydroxyapatite nanoparticles were synthesized and characterized for the first time in terms of the radiosensitivity profile. Zinc doped hydroxyapatites were produced in 4 different compositions in order to determine the best rate of doping. The samples used in all characterizations were calcined at 500 ° C for 2 hours and then sintered at 900 °C for 1 hour. X-ray diffraction patterns of the samples were found to overlap with the reference 09-0432 hydroxyapatite peaks. However, as the amount of zinc increased, beta tricalcium phosphate phases increased by 7.3%, 10%, 33% and 59% for 1%, 2%, 5% and 10 mol% zinc doped samples, respectively. As a result of fourier transform infrared spectroscopy analysis, all characteristic peaks of hydroxyapatites were observed in 1%, 2%, 5% zinc doped samples. However, for the 10% zinc doped samples, 1087 cm-1 band was lost which is showing the phosphate oxygen stretching bond. The particle sizes from the scanning electron microscope images were measured as 218, 245, 246, 302 and 352 nm for 1%, 2%, 5 % and 10% zinc doped powders, respectively. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays showed viability was after 72 hours according to pure hydroxapatite 50%, 38%, 160% and 150% for 1%, 2%, 5% and 10% zinc doped samples, respectively. An optimization study was performed to generate cell survival curves using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. According to the results of the study, it was determined that the most appropriate time was 6 and 8 days for the test. As a result of the characterization and vitablity tests, the 5% zinc added hydroxyapatite group was selected for use in the western blot test because of the high rate of beta tricalcium phosphate in 10% zinc doped hydroxyapatites. As a result of the study it was observed that 5% zinc doped hydroxyapatites were biocompatible and increased cell death rates when used with radiotherapy.