Fabrication of a core-shell-shell magnetic polymeric microsphere with excellent performance for separation and purification of bromelain

•A core-shell-shell structure magnetic polymeric microsphere was designed for the first time.•The microspheres showed excellent performance for separation and purification of bromelain.•The microspheres have the capability of thermal protection to the enzyme.•The microspheres exhibited high adsorption capacity, good stability and acceptable reusability.