In this study, copper oxide nanoparticles (CuONPs) were synthesized using Mougeotia sp. green algae and used to extract toxic lead (Pb) from water samples. The Mougeotia extract was created through an intracellular process and then mixed with copper nitrate salt (Cu(NO3)2) to synthesize the CuONPs. Characterization of the CuONPs using SEM revealed that they are agglomerated, rough, and porous rod-like nanostructures. The roughness, particle size distribution, and average diameter were calculated more precisely via Atomic Force Microscopy (AFM) to be 78.17 nm. The XRD and FTIR tests confirmed the high crystallinity and purity of the synthesized CuONPs. A good consistency was determined via the UV-vis spectroscopy regarding the stability and purity of the synthesized heterogeneous nanoparticles. Pb ions extracted from 20 mL of water samples based on the electrostatic forces of 30 mg CuONPs at pH 6.5. Chemisorption (surface complexation) occurred between the negative surface charge of the CuONPs surface and the positively charged Pb2+. Finally, the complexation of CuO and Pb could be precipitated and magnetically separated from water in a conical test tube. After elution of the solid phase (Cu-O-Pb) with nitric acid 0.5 M (1 mL) and separation of the solid phase by a Whatman filter, Pb ions were back-extracted to the eluent and determined by magnetic solid phase micro extraction (MSPME) and electrothermal atomic absorption spectrometry (ET-AAS) after dilution with DW up to 2.0 mL. The LOD, linear range, working range, and enrichment factor were obtained at 0.15 μg L-1, 0.3-7.5 μg L-1, 0.5-21 μg L-1, and 9.84, respectively.
Al-Maliki et al. (Sun,) studied this question.