Microwave assisted green synthesized copper- carrageenan bionanocomposite for efficient removal of cefixime from defile water.

Water contamination, particularly by antibiotics, poses a significant threat to both natural resources and human health due to the rise of antibiotic-resistant microorganisms. Addressing this issue requires an eco-friendly and effective solution. In this study, we synthesized a Copper-Carrageenan bionanocomposite for the photocatalytic degradation of Cefixime (CF) using a green route, avoiding traditional chemical methods. The reduction of metal ions was achieved using Argemone albiflora leaf extract, a medicinal plant not consumed by humans or animals. κ-Carrageenan, a biopolymer, encapsulated the CuO nanoparticles. The bionanocomposite was synthesized in a one-pot reaction and characterized by XRD, FTIR, TEM, XPS, and UV-Visible spectroscopy. XRD, FTIR, and EDS confirmed the incorporation of CuO nanoparticles within the carrageenan matrix. The size of the synthesized nanoparticles ranged from 11.9 to 13.8 nm, and the encapsulated BNC particles ranged from 6.8 to 4.9 nm. The bionanocomposite efficiently degraded 91.85 % of CF in 90 min under optimal conditions. Kinetic studies revealed that the photocatalytic degradation follows pseudo-first-order kinetics. Degradation conditions such as time, pH, catalyst concentration, and drug concentration were optimized. A 20 mg/L BNC catalyst was used to degrade a 20 ppm CF solution. The degradation intermediates were analysed by LCMS, and the degradation mechanism is discussed in this work.