title: Synthesis and characterization of dextran-capped silver nanoparticles with enhanced antibacterial activity.
abstract: Dextran-capped silver nanoparticles were synthesized by reducing silver nitrate with NaBH4 in the presence of dextran as capping agent. The characters of silver nanoparticles were investigated using UV-Vis spectrophotometer, nano-grainsize analyzer, X-ray diffraction, and transmission electron microscopy. Results showed that the silver nanoparticles capped with dextran were in uniform shape and narrow size distribution. Moreover, compared with polyvinylpyrrolidone (PVP)-capped silver nanoparticles, the dextran-capped ones possessed better stability. Antibacterial tests of these silver nanoparticles were carried out for Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Results suggested that the dextran-capped silver nanoparticles had high antibacterial activity against both Gram-positive and Gram-negative bacteria. In addition, the cytotoxicity in vitro of the dextran-capped silver nanoparticles was investigated using mouse fibrosarcoma cells (L929). The toxicity was evaluated by the changes of cell morphology and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay. Results indicated that these silver nanoparticles had slight effect on the survival and proliferation of L-929 cells at their minimal inhibitory concentration (MIC). After modified by dextran, the physiochemical properties of the silver nanoparticles had been improved. We anticipated that these dextran-capped silver nanoparticles could be integrated into systems for biological and pharmaceutical applications.
authors.affiliation: Department of Advanced Interdisciplinary Studies, Institute of Basic Medical Sciences and Tissue Engineering Research Center Academy of Military Medical Sciences, Beijing 100850, China.
authors.forename: Guili
authors.initials: G
authors.lastname: Yang
authors.forename: Qiuxia
authors.initials: Q
authors.lastname: Lin
authors.forename: Chunren
authors.initials: C
authors.lastname: Wang
authors.forename: Junjie
authors.initials: J
authors.lastname: Li
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Jin
authors.initials: J
authors.lastname: Zhou
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Changyong
authors.initials: C
authors.lastname: Wang
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry*; D001419:Bacteria / Q000187:drug effects*; D045744:Cell Line, Tumor; D003911:Dextrans / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D051379:Mice; D008826:Microbial Sensitivity Tests / Q000379:methods; D012834:Silver / Q000737:chemistry*; D012835:Silver Nitrate / Q000737:chemistry
chemical_list: D000900:Anti-Bacterial Agents; D003911:Dextrans; D012834:Silver; D012835:Silver Nitrate