Designing of bentonite based nanocomposite hydrogel for the adsorptive removal and controlled release of ampicillin

In pharmacy, semisynthetic antibiotics with beta-lactam ring are the most prominently used drugs. The use of these drugs for humans and animals is continuously expanding. Their presence in the water system even at low concentrations can prove to be fatal to living beings. Also, they can even grow antibiotic-resistant bacteria and thus elimination of such drugs becomes very essential. Our study is focused on batch experiments for adsorptive removal of ampicillin (AMP) and its cumulative release in different solutions using xanthan gum-cl-poly(itaconic acid)/bentonite (XG-cl-poly(IA)/BN) nanocomposite hydrogel. It was synthesized by facile microwave method. The adsorption data of AMP was analyzed using various isotherm models such as Langmuir, Freundlich, Temkin and kinetic models such as Pseudo-first order, Pseudo-second order and Intraparticle diffusion. The maximum adsorption capacity as determined from Langmuir model was 245.09 mg/g at 318 K and solution pH 7. Also, XG-cl-poly(IA)/BN nanocomposite hydrogel was evaluated for AMP release in distilled water and at different pH solutions (2.2, 5.4, 7.4 and 9.4). The maximum AMP release was observed at pH 2.2 (37%).