Biomimetic mineralization of calcium carbonate/poly (sodium p-styrenesulfonate) for lysozyme immobilization

Porous calcium carbonate/poly (sodium p-styrenesulfonate) (Ca₂CO₃/PSS) microspheres were prepared using biomimetic mineralization method for lysozyme (Ly) adsorption. The morphology of Ca₂CO₃/PSS microspheres were characterized by scanning electron microscope (SEM), x-ray diffraction (XRD) and specific surface area (SSA). The Ly adsorption behavior was verified by Fourier transform infrared (FTIR) and in situ fluorescence microscope images. The effects of PSS concentration on Ly adsorption were investigated as well. It was found that Ca₂CO₃/PSS microspheres could adsorb Ly efficiently via porous structure and electrostatic interactions. The max adsorption efficiency and capacity were 87.6 ± 1.3% and 2.63 ± 0.04 mg/ 100 mg respectively when PSS concentration was 2 mg ml⁻¹. Additionally, UV/Vis spectra and fluorescence spectra further illustrated that the immobilized Ly maintained its original structure and scarcely affected by the adsorption and desorption process. This endeavor demonstrated that the easy, one-pot method was feasible to prepared Ca₂CO₃/PSS microspheres which could be used as effective and easy candidate for Ly fixation and separation. (paper)