Structure and cell viability of Pd substituted hydroxyapatite nano particles

Abstract
Palladium (II) and Sulphate ions substituted with Hydroxyapatite (HAP) of the formula: [PdxCa10-x(PO4)(5.6)(SO4-2)(0.4)(OH)(2)] was synthesized using microwave assisted co-precipitation method. The formed specimens were investigated via x-ray diffraction (XRD), Fourier transform infra-red (FTIR) and Field emission scanning electron microscopy (FESEM). Lattice parameters were computed and showed that the ionic substitutions play a significant role in changing of HAP lattice. It was also shown that the co-substituent was totally incorporated in HAP structure. FESEM showed that the grain size decreased from 100 nm at x = 0.0 to 40 nm at x = 1.0 while the crystallite size which is calculated using XRD decreased from 30.7 nm at x = 0.0 to 11.6 nm at x = 1.0. Moreover, the cytotoxicity of Pd/S-HAP was investigated and it increased with increasing Pd2+ substitution. At x = 0.0, the cytotoxicity of HAP achieved 21.88% whereas the IC50 concentration was 3.07 mg ml(-1). In addition, the chemotherapeutic effect of sample at x = 1.0 was tested on lung cancer cells (A549) in vitro. The results revealed that cancer cells were inhibited compared with the control sample. This work may encourage more investigation on Pd/S-HAP as a promising material for cancer therapy.