Photoactivated Biological Activity of Transition‐Metal Complexes

Abstract

Keywords: Photochemistry / CO releasing molecules / NO releasing molecules / Biological activity / Prodrugs / DNA cleavage Photochemical activation is a very attractive way to achieve precise spatial and temporal control of the biological action of transition-metal complexes that behave as inactive "prodrugs" in the dark. A significant amount of work has been devoted to metal complexes that act on DNA. In this area, focus has been on ruthenium and rhodium polypyridyl compounds, but copper, iron, cobalt, and vanadium complexes also find increasing application as photoactivable DNA cleaving agents, with excitation sometimes even possible in the near IR region. Most often, the activity of these systems is based on the formation of reactive radical species. Another

Photo-Controlled Release of NO and CO with Inorganic and Organometallic Complexes

“…Ruthenium nitrosyl complexes are generally quite robust, and this thermal stability as well as the known photo-lability of such species has drawn considerable attention to these as possible photoNORMs [20,63,67,[87][88][89][90][91][92][93][94][95][96][97][98][99][100][101]. .…”

The photochemistry of transition metal complexes using density functional theory

“…In recent years, an increasing number of photoactive metal complexes have been investigated for application as anti-cancer prodrugs [6,83]. Non-toxic precursors can be activated by light excitation to form cytotoxic species that act with novel mechanisms of action.…”

Near-IR mediated intracellular uncaging of NO from cell targeted hollow gold nanoparticles

“…One approach is to use light to trigger NO release (''uncaging'') from an otherwise inactive precursor, thus allowing precise control of the timing and location of this event. There are now numerous examples of NO uncaging using donor molecules photoactivated by UV-to-visible light; [4][5][6][7] however, strong absorptions of cellular components, especially DNA and hemes, interfere with application of these shorter wavelengths. 8 Given that near-infrared light penetrates more deeply and is relatively benign to tissue, these laboratories 9,10 and others 11,12 have been interested in designing systems that employ NIR wavelengths to trigger the photochemical uncaging of various bioactive small molecules.…”