Preparation, characterization, antimicrobial and cytotoxicity studies of copper/zinc- loaded montmorillonite.
BACKGROUND
A series of modified montmorillonites (Mt) including zinc-loaded Mt (Zn-Mt), copper-loaded Mt (Cu-Mt), copper/zinc-loaded Mt with different Cu/Zn ratio (Cu/Zn-Mt-1, Cu/Zn-Mt-2, Cu/Zn-Mt-3) were prepared by an ion-exchange reaction, and characterized using X-ray diffraction (XRD), fourier transformed infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The specific surface areas, antimicrobial activity and cytotoxicity of the modified Mt were investigated.


RESULTS
In the modified Mt, hydrated Cu ions and Zn ions were exchanged in the interlayer space of Mt and the particles were irregular shapes. The results showed that Cu/Zn-Mt enhanced antibacterial and antifungal activity compared with Zn-Mt and Cu-Mt possibly due to the synergistic effect between Cu and Zn. Among the Cu/Zn-Mt with different Cu/Zn raitos, Cu/Zn-Mt with a Cu/Zn ratio of 0.98 or 0.51 showed higher antimicrobial activity against gram-negative bacteria (Escherichia coli), gram-positive bacteria (Staphylococcus aureus),fungi (Candida albicans).Moreover, the antimicrobial activity of Cu/Zn-Mt was correlated with its specific surface area. Cytotoxicity studies on IPEC-J2 cell showed a slight cytotoxicity of Cu/Zn-Mt.


CONCLUSIONS
The current data provide clear evidence that in terms of its antimicrobial activity and relatively low toxicity, the Cu/Zn-Mt holds great promise for applications in animal husbandry.
Animal Science College, Zhejiang University, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, No.866, Yuhangtang Road, Hangzhou, 310058 People's Republic of China.
Lefei
L
Jiao
Animal Science College, Zhejiang University, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, No.866, Yuhangtang Road, Hangzhou, 310058 People's Republic of China.
Fanghui
F
Lin
Animal Science College, Zhejiang University, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, No.866, Yuhangtang Road, Hangzhou, 310058 People's Republic of China.
Shuting
S
Cao
Animal Science College, Zhejiang University, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, No.866, Yuhangtang Road, Hangzhou, 310058 People's Republic of China.
Chunchun
C
Wang
Animal Science College, Zhejiang University, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, No.866, Yuhangtang Road, Hangzhou, 310058 People's Republic of China.
Huan
H
Wu
Animal Science College, Zhejiang University, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, No.866, Yuhangtang Road, Hangzhou, 310058 People's Republic of China.
Miaoan
M
Shu
Animal Science College, Zhejiang University, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, No.866, Yuhangtang Road, Hangzhou, 310058 People's Republic of China ; Key Laboratory of Animal Nutrition and Feed in East China, Ministry of Agriculture, No.866, Yuhangtang Road, Hangzhou, 310058 People's Republic of China.
Caihong
C
Hu
Antimicrobial reagent; Modified montmorillonites; Synergistic antimicrobial effect