Du Wen-Li, Xu Ying-Lei, Xu Zi-Rong, Fan Cheng-Li
Institute of Feed Science, College of Animal Science, Zhejiang University, Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Hangzhou 310029, People's Republic of China.
Nanotechnology. 2008 Feb 27;19(8):085707. doi: 10.1088/0957-4484/19/8/085707. Epub 2008 Feb 4.
The present study was conducted to prepare and characterize chitosan nanoparticle loaded copper ions, and evaluate their antibacterial activity. Chitosan nanoparticles were prepared based on ionotropic gelation, and then the copper ions were loaded. The particle size, zeta potential and morphology were determined. Antibacterial activity was evaluated against E. coli K(88) by determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) in vitro. Results showed that the antibacterial activity was significantly enhanced by the loading of copper ions compared to those of chitosan nanoparticles and copper ions. The MIC and MBC of chitosan nanoparticle loaded copper ions were 21 times and 42 times lower than those of copper ions, respectively. To confirm the antibacterial mechanism, morphological changes of E. coli K(88) treated by chitosan nanoparticle loaded copper ions were dynamically observed with an atomic force microscope (AFM). It was found that chitosan nanoparticle loaded copper ions killed E. coli K(88) through damage to the cell membrane.
本研究旨在制备并表征负载铜离子的壳聚糖纳米颗粒，并评估其抗菌活性。基于离子凝胶法制备壳聚糖纳米颗粒，然后负载铜离子。测定了颗粒大小、zeta电位和形态。通过体外测定最低抑菌浓度（MIC）和最低杀菌浓度（MBC），评估了对大肠杆菌K(88)的抗菌活性。结果表明，与壳聚糖纳米颗粒和铜离子相比，负载铜离子显著增强了抗菌活性。负载铜离子的壳聚糖纳米颗粒的MIC和MBC分别比铜离子低21倍和42倍。为了确认抗菌机制，用原子力显微镜（AFM）动态观察了负载铜离子的壳聚糖纳米颗粒处理的大肠杆菌K(88)的形态变化。发现负载铜离子的壳聚糖纳米颗粒通过损伤细胞膜杀死大肠杆菌K(8)。
