Preparation and Characterization of Novel Antimicrobial Cu-Al Layered Double Hydroxide Filled Polyvinyl Alcohol/chitosan Nanofibers with Peroxidase-Mimic Activity

In this work, the Cu-Al layered double hydroxide/polyvinyl alcohol/chitosan composite (Cu-Al LDHs/PVA/CS) nanofibers were prepared through electrospinning technology. The characteristics of the synthesized materials were investigated using different methods, including field emission scanning electron (FESEM), Fourier -transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). Then, the enzyme-mimic activity of Cu -Al LDHs and Cu-Al LDHs/PVA/CS nanofibers was tested, and the results confirmed the peroxidase-like activ-ity of the prepared materials. Under the optimum conditions, kinetic parameters were calculated. The obtained Km values for Cu-Al LDHs were 0.169 mM (TMB) and 0.087 mM (H2O2), and for Cu-Al LDHs/PVA/CS nanofibers were 0.0.078 mM (TMB) and 0.037 mM (H2O2). These results confirmed the high affinity of Cu-Al LDHs/PVA/CS nanofibers toward their substrate, and the immobilization of LDHs on PVA/CS nanofibers enhances their peroxidase-mimic activity. On the other hand, the antibacterial activity of prepared materials was tested against B. subtilis and E. coli. The obtained results indicated a higher antibacterial activity of PVA/CS/Cu-Al LDHs than Cu-Al LDHs and PVA/CS nanofibers. Also, it was observed that PVA/CS/Cu-Al LDHs scaffolds have a stronger inhibitory effect on B. subtilis than E. coli. These composite nanofibers open new avenues toward using natural materials as potent antibacterial agents.