Removal of Cephalexin-Antibiotic from Drinking Water by Designing CaCl2 Incorporated Chitosan Co- Tragacanth Gum Composite Hydrogel

Background: The prevalence of antibiotic contaminants in aquatic environments presents a critical challenge to public health, necessitating the development of efficient removal methods. Emerging pollutants, especially antibiotics, have been implicated in the rise of antibiotic-resistant bacteria, threatening ecological balance and human well-being. Objective: This study aims to synthesize and evaluate the efficacy of a CaCl2-based composite hydrogel using chitosan as a biopolymer for the adsorption of antibiotic pollutants from water, targeting the improvement of water purification technologies in healthcare settings. Methods: Chitosan-based composite hydrogels were synthesized via free radical polymerization, incorporating CaCl2 and utilizing techniques such as Field Emission Scanning Electron Microscopy (FESEM) for morphology analysis, Energy-dispersive X-ray (EDX) analysis for elemental verification, Fourier-transform infrared spectroscopy (FTIR) for functional group identification, and X-ray diffraction (XRD) to determine crystallinity. Physicochemical parameters, including contact time, pH, temperature, reusability, and swelling behavior in various media, were systematically assessed to ascertain the hydrogel's adsorptive performance. Results: The synthesized hydrogels demonstrated a porous and rough surface ideal for adsorption, with an initial antibiotic removal rate of 80% within 30 minutes of contact time. FTIR analysis confirmed the presence of functional groups corresponding to absorption bands at 1053, 1415, 1601, 2600, 2900, 3300, and 3500 cm-1. EDX and XRD analyses affirmed the incorporation of CaCl2, with a crystalline phase characterized by sharp peaks. The hydrogel's maximum adsorption efficiency reached 95% at an optimized adsorbent dose of 0.05 g. Conclusion: The CaCl2-based composite hydrogel exhibits significant potential for the removal of antibiotic pollutants from water, suggesting a viable approach to mitigate the environmental impact of pharmaceutical contaminants and enhance human health by reducing the spread of antibiotic resistance.