Preparation of Calcium Phosphate Nanoparticles: Study their Characterization and Antibacterial Activity

Calcium phosphate nanoparticles (CPNPs) have been synthesized by chemical precipitation method and were characterized by UV-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The antibacterial activity against multi-drug resistant (MDR) gram-negative bacteria Pseudomonas aeruginosa (P. aeruginosa) and Klebsiella pneumonia (K. pneumonia) was performed by well diffusion method, using different concentrations of CPNPs and different combinations of CPNPs with ciprofloxacin (CIP) (CIP-CPNP100, CIP-CPNP50, and CIP-CPNP25). The minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) were evaluated by the broth dilution method and optical density. Cytotoxicity of nanoparticles was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on polymorphonuclear cells. Results indicated that synthesized CPNPs sized 28.02 ± 3.2 nm in diameter as average, with distorted spherical shape appears as agglomerates. CPNPs showed no antibacterial activity against MDR bacteria, but combining them with CIP recorded antibacterial activity represented by inhibition zone against MDR bacteria. It was found that the inhibition zone increases when the concentration of CIP and particle size decreases. The MTT assay reveals the acceptable toxicity of the synthesized nanoparticles. The present study can be helpful to formulate nano-drug conjugates as antimicrobial agents in various fields of medical research.