Chitosan-based adsorbents for adsorptive confiscation of antibiotic and NSAID contaminants from water bodies: a short review

The development in science and technology over the past few decades has changed the world a lot. In view of the changes caused in the environment, the results are disturbing. One such example is the bloom of the pharmaceutical industry which has lead to synthesis of many drugs which possess potency for curing a number of diseases. However, the accumulation of the unused drugs in semi-metabolized state in the natural water systems through manufacturing plants, hospitals or consumers at large, have led to a serious trouble. This review article aims to present a short summary of the various methods proposed for the removal of antibiotics and non-steroidal Anti-Inflammatory Drugs (NSAIDs) from aquatic systems through adsorbents synthesized using chitosan and its different structurally modified versions. Chitosan, being abundantly available in nature, has become the most preferable material as adsorbent for a variety of contaminants including dyes, heavy metals, fluoride, drugs, fertilizers, etc. Thus, we present three important structural modifications of chitosan namely crosslinked/grafted chitosan, chitosan hydrogels/microspheres and chitosan composites as potential adsorbents for commonly used antibiotics and drugs. The study also includes the optimized pH conditions for adsorption, isotherm, kinetics and mechanism of adsorption as well as maximum adsorption capacity obtained for the drug.

Graphic abstract