Short-Circuiting the Molecular Wire: Cooperative Binding of Δ -[Ru(phen)_2dppz]~2+ and Δ-[Rh(phi)_2bipy]~3+ to DNA

摘要

In conclusion, we have strong spectroscopic evidence that Δ-[Ru(phen)_2dppz]~2+ and Δ-[Rh(phi)_2bipy]~3+ bind cooperatively to a [poly(dA-dT)]_2 duplex and that the remarkable quenching properties of Δ-RH can be quantitatively described by a coop- erative binding model where ET only occurs from donors bound adjacent to acceptors. This "short circuiting" offers an explana- tion for the Δ-RH-loading-invariant electron transfer rates found by others and the highly stereospecific quenching efficiency.