Biogenic Synthesis of Iron Oxide Nanoparticle Using Padina Pavonica Extract: Application for Photocatalytic Degradation of Congo Red Dye, Neurotoxicity and Antioxidant Activity

The current study focused on green synthesis of iron nanoparticles by Padina pavonica (Pa@FeNPs), removal activity of dye CR (Congo Red) and investigating antioxidant and neurotoxicity activities. The morphological and physical properties of Pa@FeNPs were characterized by FT-IR (Fourier Transform Infrared Spectroscopy), XRD (X-Ray Diffractometer), SEM (Scanning Electron Microscopy), EDX (X-Ray Spectroscopy), TEM (Transmission Electron Microscopy) and Zeta potential analyses. XRD and zeta potential analyses revealed a potential of-8.53 mV and formation of cubic crystals with an average dimension of 10.53-20.55 nm. The optimum conditions of pH, temperature, initial dye concentration and adsorbent amount for CR removal were found to be 4, 40°C, 20 ppm and 20 mg respectively. The CR removal percentage using Pa@FeNPs reached a very high efficiency of 95%. Langmuir Isotherm model (R2=0.99, 25°C) were best fitted to our data for evaluating dye adsorption behaviors of the Pa@FeNPs. Metal chelating activity in the aqueous extract of P. pavonica and Pa@FeNPs was found to be 74.71±2.16% and 64.95±0.42%, respectively. Inhibitory concentration 50 (IC50) values for P. pavonica aqueous extract and Pa@FeNPs were found to be 0.128 μg/mL and 400 μg/mL, respectively in the SH-SY5Y (Human neuroblastoma).