Labeling Cells with Silver/Dendrimer Nanocomposites.

摘要

We have developed water-soluble, biocompatible, fluorescent, and photostable silver/dendrimer nanocomposites that have a potential to be used for in vitro cell labeling. A PAMAM(underline)E5.NH2 dendrimer was used as a template to prepare first a silver-dendrimer complex in an aqueous solution at biologic pH=7.4. Conversion into nanocomposite was achieved by irradiating the solution of the (Ag+)25-PAMAM(underline)E5.NH2 complex by UV light to reduce the bound Ag+ to zero- valent Ag0 atoms, which were simultaneously trapped in the dendrimer network. Results indicate that the (question mark)(Ag0)25-PAMAM (underline)E5.NH2(exclamation point) silver/dendrimer nanocomposite forms positively charged single particles of 4-5 nm under the experimental conditions used. The dendrimer nanocomposite proved to be fluorescent. Toxicity testing of (question mark)(Ag0)25-PAMAM (underline)E5.NH2(exclamation point) nanocomposite revealed a behavior similar to the template dendrimer. Intracellular internalization of the silver nanocomposite and cell labeling capabilities was confirmed by confocal microscopy.