Adsorption of amoxicillin by chitosan and alginate biopolymers composite beads.

Abstract

Amoxicillin is one of the most used antibiotics worldwide, and due to incomplete metabolism in the human body or inadequate disposal, it has been detected in the receiving water bodies. One of the major concerns is the promotion of antibiotic resistance, as well as its toxicity to aquatic organisms such as fish, invertebrates, and algae, and its ability to disrupt the natural microbial communities in water bodies. Moreover, water and wastewater treatment plants struggle to effectively treat water contaminated with amoxicillin. Consequently, new processes need to be explored to complement traditional water and wastewater treatments. Adsorption, being a relatively economical and simple technique, appears promising for this purpose. Numerous adsorbents are found in the literature to adsorb drugs, however, the fabrication of all these adsorbents involves various complex steps and substances when compared to the chitosan and alginate beads. Therefore, the objective of this study was to assess the adsorption of amoxicillin on chitosan and alginate beads. The optimal pH was found to be 4 for both beads. The kinetics study indicates that external diffusion governs adsorption for alginate, while internal diffusion governs adsorption for chitosan. Thermodynamic parameters demonstrated that adsorption is a spontaneous and endothermic process.