A role for in vitro cytotoxicity testing in the selection and development of metal-based pharmaceutical and materials products.

During the research and development process many similar chemicals or materials may be synthesized that accomplish the required task. The most promising examples then have to be selected for further development. This is primarily achieved by assessing performance in function tests. Where relative toxicity is important, cytotoxicity testing is an effective way of further ranking the potential products. Though cytotoxicity cannot be used to predict precisely in vivo toxicity, used in this fashion it can be successfully incorporated into the selection procedures of a product research and development programme. Four applications of cytotoxicity testing in an industrial research environment will be discussed. Primary screening of metal complexes for potential antitumour activity by evaluating selective cytotoxicity against a panel of human tumour-derived cell lines. The cytotoxicity of a class of novel gold-phosphine complexes with antibacterial activity was assessed against the CHO cell line in order to select compounds with a favourable in vitro therapeutic index. The VERO cell line was used to assess the cytotoxicity of a number of AgCl/TiO(2) compositions with antibacterial activity as part of a biomaterials programme designed to produce materials suitable for incorporation into medical devices. Cytotoxicity against the CHO cell line was used to select possible components for new liquid gold compositions for application to ceramic materials.