Influence of adding Pluronic F127 in the electrolyte on the morphology, structure and biofilm adhesion of calcium phosphate coatings

In this work, we have investigated the addition of Pluronic F127 (PF127) into the electrolyte solution on the structure, morphology and antibacterial growth of calcium phosphate (CaP) coatings synthesized by an electrochemical method on Ti substrate. Different parameters of the deposition process were investigated, which were temperature, time and PF127 wt%. The coatings were characterized by X-ray diffraction (XRD), gravimetric analysis, Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In vitro antimicrobial assays against S. aureus were performed. XRD analysis confirmed the formation of dicalcium phosphate dihydrate (DCPD) or anhydrous dicalcium phosphate (DCPA) and octacalcium phosphate (OCP). The structure and morphology depended mainly on PF127 wt% and deposition temperature in lower deposition time. Interestingly, structure and morphology were not influenced by adding PF127 at higher deposition time using higher PF127 concentrations. The morphology by SEM changed from plate-like to fiber by varying the PF127 concentration as well as blocks at higher temperatures. Moreover, all coatings were crystalline, uniform and crack-free. Antibacterial assays showed that biofilm formation was prevented when a coating of PF127 is deposited on the surface. Bacterial growth depended on the phase and morphology of washed coatings. Thus, the structure, morphology and consequently bacterial growth resistance can be tailored by the use of PF127 in the electrochemical processing at shorter deposition times.