Study On Magnetic Nanoparticle Antibacterial Materials With Multiple Action Mechanism

People’s healthy consciousness gradually grows with the improvement of living standard. The demand for antibacterial products is increasing. There are mainly three kinds of antibacterial strategies of adhesion resistance, contact killing, and biocide agent leaching. However, each antibacterial approach has its own advantages and defects in different circumstances. In this paper, two kinds of bi-functional antibacterial materials were prepared by combining contact killing with biocide agent leaching mechanism.Magnetic nanoparticles not only have unique magnetic property, but also have the characteristics of nanoparticles. It is an excellent carrier. Magnetic separation technology was introduced in the antibacterial materials, which could be used to separate and recycle antibacterial materials and greatly improved the utilization value of antibacterial materials.1. Quaternary ammonium/N-halamine-functionalized magnetic nanoparticles were prepared by soap-free emulsion polymerization. Magnetic nanoparticles were coated by two kinds of antibacterical polymer. The morphology and chemical composition of modified nanoparticles were characterized by thermogravimetric analysis (TGA), fourier transform infrared spectra (FT-IR), X-ray photoelectron spectra (XPS), and transmission electron microscope (TEM). The antibacterial experiment showed that the bi-functional antibacterial nanoparticles killed above 99.95% E. coli and above 99.99% S. aureus after contacting 15 min. The magnetic antibacterial nanoparticles retained excellent biocidal efficiency during five exposure/collect/recycle procedures.2. Quaternary ammonium/nano silver modified magnetic nanoparticles were prepared by layer-by-layer self assembly technology and in situ self reaction, and were characterized by scanning electron microscopy (SEM), fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and Zeta potential. The observed zone of inhibition for the immobilized Ag nanoparticles composites indicated that the biocidal nano silver were released from the composites in aqueous. The quaternary ammonium/nano silver modified magnetic nanoparticles killed above 99.74% E. coli and above 99.04% S. aureus after contacting 60 min. The magnetic antibacterial nanoparticles retained excellent biocidal efficiency during five exposure/collect/recycle procedures.