摘要
Contamination resulting from microbial adhesion on magnesium alloys is very common in many applications. Self-assembly technology was employed to prepare an antibacterial composite coating by fixing silver nanoparticles （AgNPs） onto the surface of magnesium alloys. The AgNPs were immobilized on the surface of 3-aminopropyltrimethoxysilane （APTMS）-modified magnesium alloy AZ31 （APTMS/Mg） through electrosta- tic inter-attraction between partially protonated amino groups and negatively charged citrate-capped AgNPs, resulting in the AgNPs attached APTMS/Mg （AgNPs/APTMS/Mg） substrate. The prepared Ag colloid and functionalized AZ31 alloy were characterized by ultraviolet-visible （UV-vis） spectroscopy, Fourier transform infrared （FTIR） spectroscopy, scanning electron microscopy （SEM）, and electrochemical methods. Finally, the bactericidal activity of AgNPs/APTMS/Mg substrate against Escherichia coli was assessed by the inhibition zone. The results demonstrated that Si-O-Si covalent bonds existed on the substrate with the formation of inorganic Si-O-Mg bonds. AgNPs were immobilized and well-dispersed, forming a uniform submonolayer on the silane film in two dimensions. The AgNPs/APTMS-pretreated AZ31 alloys exhibited better corrosion resistance and excellent antibacterial performance.
Contamination resulting from microbial adhesion on magnesium alloys is very common in many applications. Self-assembly technology was employed to prepare an antibacterial composite coating by fixing silver nanoparticles （AgNPs） onto the surface of magnesium alloys. The AgNPs were immobilized on the surface of 3-aminopropyltrimethoxysilane （APTMS）-modified magnesium alloy AZ31 （APTMS/Mg） through electrosta- tic inter-attraction between partially protonated amino groups and negatively charged citrate-capped AgNPs, resulting in the AgNPs attached APTMS/Mg （AgNPs/APTMS/Mg） substrate. The prepared Ag colloid and functionalized AZ31 alloy were characterized by ultraviolet-visible （UV-vis） spectroscopy, Fourier transform infrared （FTIR） spectroscopy, scanning electron microscopy （SEM）, and electrochemical methods. Finally, the bactericidal activity of AgNPs/APTMS/Mg substrate against Escherichia coli was assessed by the inhibition zone. The results demonstrated that Si-O-Si covalent bonds existed on the substrate with the formation of inorganic Si-O-Mg bonds. AgNPs were immobilized and well-dispersed, forming a uniform submonolayer on the silane film in two dimensions. The AgNPs/APTMS-pretreated AZ31 alloys exhibited better corrosion resistance and excellent antibacterial performance.
基金
supported by National Natural Science Foundation of China(No.51241001)
NSF of Shandong Province(No.ZR2011EMM004)
open foundation of State Key Laboratory for Corrosion and Protection(NoSKLCP21012KF03)
Taishan Scholarship Project of Shandong Province(No.TS20110828)
Basic Research Project of Qingdao Science and Technology Program(No.13-1-4-171-jch)
