Figure 9.

Microscopic images of HeLa (A–F) and J774A1 cells (G–L) treated with Au nanostructures. A–F) HeLa cells were treated with gold nanoclusters over 0, 1, or 12 h time. Cells were fixed, stained, and seen with an optical microscope (A,C,E) and with and scanning electron microscope (B,D,F). G–L) J774A1 macrophages were treated for 1 h and imaged using an optical microscope. AuNPs of 15 nm diameter stained the endocytic compartment of the cells black sparing the nucleus (K). Cytotoxicity of AuNPs against four cell lines (HeLa, SK‐Mel‐28, L929, and J774A1). M) HeLa cells were seeded at 2000 cells per well and were treated with AuNPs for 48 h and MTT tests were carried out for the evaluation of cell viability. N) IC₅₀ values of Au 1.4MS were lowest across all cell lines and that AuNPs of smaller or larger size were progressively less cytotoxic, revealing a size dependent cytotoxicity. Adapted with permission.^{[ 194 ]} Copyright 2007, Wiley.