Cytotoxicity, neutral/cationic complexes

Complexes 25a-25c contain a benzimidazolylidene NHC ligand coordinated to a gold(I) center as well as a second coordinated ligand, which is chlorido, triphenylphosphane, or the same NHC structure [100]. Interestingly, the cationic biscarbene derivative 25c is a substantially weaker inhibitor of TrxR than the neutral chlorido complex 25a and the cationic phosphane derivative 25b. However, both cationic complexes have higher cytotoxic activity than the neutral 25a. For the cationic complexes, an enhanced cellular uptake with an increased... 

Nolan and coworkers reported the cytotoxicity of different neutral and cationic complexes. The first series of systems studied were Au-IPr derivatives bearing biocompatible moieties such as amino acids (L-proline or L-cysteine, Figure 7.16) [17]. In parallel, a second series of systems was selected, as it is well-known in the literature that cationic gold complexes can induce apoptosis of cancer cell lines. The IC50 were measured with LNCaP (prostate carcinoma) and MDA MB231 (breast carcinoma). 

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