Green Synthesis of Phosphorous-Containing Hydroxyapatite Nanoparticles (nHAP) as a Novel Nano-Fertilizer: Preliminary Assessment on Pomegranate (Punica granatum L.)

Nano-fertilizers are innovative materials created by nanotechnology methodologies that may potentially replace traditional fertilizers due to their rapid absorption and controlled distribution of nutrients in plants. In the current study, phosphorous-containing hydroxyapatite nanoparticles (nHAP) were synthesized as a novel phosphorus nano-fertilizer using an environmentally friendly green synthesis approach using pomegranate peel (PPE) and coffee ground (CE) extracts. nHAPs were physicochemically characterized and biologically evaluated utilizing the analysis of biochemical parameters such as photosynthetic activity, carbohydrate levels, metabolites, and biocompatibility changes in Punica granatum L. Cytocompatibility with mammalian cells was also investigated based on MTT assay on a Vero cell line. Dynamic light scattering (DLS) and zeta potential analysis were used to characterize the nHAPs for size and surface charge as well as morphology using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The nHAPs were found to have different shapes with average sizes of 229.6 nm, 120.6 nm (nHAPs_PPE) and 167.5 nm, 153 nm (nHAPs_CE) using DLS and TEM, respectively. Overall, the present results showed that the synthesized nHAPs had a negative impact on the selected biochemical, cytotoxic, and genotoxic parameters, indicating that the evaluation of nHAP synthesized by this approach has a wide range of applications, especially as a nano-fertilizer.