Figure 1.

Turbidity measurement at 320 nm of Fe/Mg-carbonate apatite (Fe/Mg-CA) nanoparticles (NPs) formed by mixing increasing concentrations of exogenous Mg²⁺ (0, 2, 4, 6, 8 and 10 mM) in a fixed concentration of exogenous Ca²⁺ (4 mM Ca²⁺) and two different (low and high) concentrations of Fe³⁺, 1 µM and 5 µM in 1 mL Dulbecco’s modified eagle medium (DMEM), followed by incubation at 37 °C for 30 min and supplementation with 10% fetal bovine serum (FBS).