Antibacterial activity of microwave-hydroxyapatite and cellulose blend

The aim of the work was to synthesize a microwave-hydroxyapatite and cellulose nanocrystal (HApM/CNC) blend and investigate it for its antibacterial efficacy in water treatment applications. The blend was synthesized at varying ratios (100: 0, 80: 20, 60: 40, and 40: 60) and evaluated using disc diffusion, optical density (OD), and colony-forming unit (CFU) tests. Structural, functional group, and morphological analyses were conducted using X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). Antibacterial activity tests revealed enhanced antibacterial efficacy in the HApM/CNC blend. The inhibition zones for the blend measured 13.6 mm for E. coli and 17 mm for S. aureus, surpassing the 7.5 and 9.5 mm zones for pure HApM and the 10.5 and 10 mm zones for pure CNC, respectively. OD and CFU tests further corroborated these results, indicating a consistent pattern of increased antibacterial activity in the blends. XRD analysis revealed a calcium pyrophosphate phase associated with the employed microwave technique, further validated by FTIR spectra. SEM mophology confirmed the blend’s surface roughness, which improved antibacterial efficacy. The microwaved combustion created possible radical species thought to be the cause of the increased antibacterial activity seen. This study highlights the potential of HApM/CNC blends for effective antibacterial applications in water treatment.