Polycaprolactone/clove oil/nano-carbonated hydroxyapatite nanofibrous scaffolds: Physicochemical properties and antibacterial activity for bone tissue engineering

This study aimed to synthesize polycaprolactone (PCL)/gelatin/nano-carbonated hydroxyapatite (n-CHAp) and PCL/clove oil/n-CHAp composite-based nanofibrous scaffolds and to analyze the effects of biocomposite variations on the morphology, crystallinity, chemical structure, and antibacterial activity of the scaffolds. The nanofibrous scaffolds were synthesized via electrospinning. Scaffold morphology was characterized using Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDS), the chemical structure was analyzed using Fourier Transform Infrared Spectroscopy (FTIR), and the crystal structure was analyzed using X-Ray Diffractometer (XRD). The antibacterial activity of the scaffolds was evaluated against Pseudomonas aeruginosa and Staphylococcus aureus using the Total Plate Count (TPC) method. The scaffolds primarily consisted of a continuous fibrous structure with fiber diameters ranging from 154 to 1282 nm, although only the finest fibers (154 –376 nm) closely resembled the natural extracellular matrix (ECM). FTIR analysis confirmed the presence of functional groups characteristic of PCL and gelatin, as well as phosphate and carbonate bands derived from n-CHAp, without the formation of new chemical bonds. Meanwhile, XRD results showed crystallite sizes ranging from 22.9 to 24.8 nm, with relatively constant PCL lattice parameters. Antibacterial testing revealed differences in activity among the formulations. The PCL/clove oil/n-CHAp formulation exhibited the highest numerical inhibition rate; however, its difference from the PCL/clove oil formulation was not statistically significant. Among the formulations studied, the PCL/clove oil/n-CHAp formulation exhibited the highest antibacterial activity, whereas the addition of gelatin and n-CHAp provided favorable physicochemical properties. Further mechanical and biological evaluations are required to determine the most suitable scaffold formulation for bone tissue engineering applications.