Cerium-doped hydroxyapatite nanoparticles synthesized by the co-precipitation method

Abstract

The present work reports a simple adapted co-precipitation method for the synthesis of stable Ce-substituted Ca hydroxyapatite (HAp) nano­particles. The structural and morphological properties of the Ce-doped hydro­xyapatite (Ce:HAp) were characterized by X-ray diffraction (XRD), trans­mission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX). The optical properties of the Ce-doped hydroxyapatite were also investigated using Fourier transform infrared (FTIR) spectroscopy, Fourier transform Raman spectroscopy and photolumine­scence analysis. The results of the XRD studies revealed the progressive inc­rease in the a- and c-axes with increasing Ce concentration. In the FTIR studies of Ce:HAp pow­ders, a structure similar to that of hydroxyapatite was observed. The IR and Raman wavenumbers and the peak strengths of the bands asso­ciated with the P–O and O–H bonds decreased progressively with increasing Ce concentration. All the emission maxima could be attributed to 5d–4f tran­sitions of the Ce ions. The displacements of the maximum emission bands with increasing Cerium in the samples were in agreement with the results obtained by XRD studies. The Ce:HAp samples with xCe = 0.03 and 0.05 exhibited significant antibacterial activity against Staphylococcus aureus and Escherichia coli bacterial strains compared to Ce:HAp samples with xCe = 0 (pure HAp) and 0.01.