Highly adsorptive removal of antibiotic and bacteria using lysozyme protein modified nanomaterials

•Lysozyme protein adsorption on nanosilica was controlled by both electrostatic and non-electrostatic interactions.•The lysozyme modified nanosilica (LMNS) increased LFX removal dramatically from 51.51% to 80.63%.•Optimum conditions for LFX removal were pH 8.0, contact time 90 min, adsorbent dosage 10 mg/mL.•Adsorption of LFX on LMNS was mainly governed by electrostatic attraction.•The removal efficiencies of E.coli and Bacillus removal using LMNS were greater than 90 %. In this paper, we studied adsorption of protein lysozyme on nanosilica and their applications for removal of levofloxacin (LFX) antibiotic and bacteria Escherichiacoli(E.coli) and Bacillus in water environment. Solution pH 10, contact time 120 min, nanosilica dosage 10 mg/mL and 1 mM KCl were the best conditions for lysozyme adsorption on nanosilica to form biomaterial, namely lysozyme modified nanosilica (LMNS). The optimal parameters for the removal of LFX using LMNS were determined to be 90 min of adsorption time, pH 8, and 10 mg/ml of adsorbent. Adsorptive removal of LFX dramatically increased in ideal circumstances, going from 51.51% to 80.63% when using LMNS. Two-step and Freundlich models were used to represent isothermal adsorption of LFX on LMNS at different strengths while a pseudo-second-order achieved the best fit for LFX adsorption kinetic on LMNS. The amount of LFX that adsorbs to LMNS reduced as salt concentration increased, suggesting that electrostatic interaction was primarily responsible for the adsorption. After four regenerations, LFX removal was greater than 60%, proving that LMNS is highly effective in removing LFX. The removal of E.coli and Bacillus were reached greater than 90 % that were much higher than other materials. Both electrostatic and hydrophobic interactions governed the removal of E.coli and Bacillus. Our results indicate that LMNS is an excellent bio-adsorbent for removal of antibiotic and bacteria in aqueous solution.