Solar Light-Assisted Oxidative Degradation of Ciprofloxacin in Aqueous Solution by Iron(III) Chelated Cross-Linked Chitosan Immobilized on a Glass Plate

The massive worldwide use of antibiotics leads to water pollution and increasing microbial resistance. Hence, the removal antibiotic residues is a key issue in remediation. Here, we report solar light-assisted oxidative degradation ciprofloxacin (CPF), using H2O2 aqueous solution, catalyzed by iron(III) chelated cross-linked chitosan (FeIII-CS-GLA) immobilized on glass plate. FeIII-CS-GLA catalyst was characterized FTIR 57Fe-Mössbauer spectroscopies as well X-ray diffraction, revealing structural motifs high-spin ferric character metal. Catalytic CPF investigated function light irradiation time, solution pH, concentration CPF, cross-linker dosage content FeIII-CS-GLA. system found serve an efficient with maximum at pH 3. specific ·OH scavenger mannitol significantly reduces rate, indicating that hydroxyl radicals play role. mechanism catalytic evaluated terms pseudo-first-order Langmuir-Hinshelwood kinetic models; adsorption onto surface evidenced field emission scanning electron microscopy coupled energy dispersive spectroscopy. can be reused multiple times only minor loss efficiency. Antimicrobial activity tests performed against both Gram-negative (Escherichia coli DH5?, Salmonella typhi AF4500) Gram-positive bacteria (Bacillus subtilis RBW) before after treatment confirmed complete CPF. These results establish rugged for photo-Fenton type solutions.