Efficient DNA photocleavage promoted by a Tb(III) complex

This work demonstrates the efficient photocleavage of DNA induced by a terbium complex. Mechanistic studies and DNA groove binding dependence were performed to better understand the photo-cleavage reaction, suggesting the presence of oxygen and carbon-centered radicals in the strand scission event. Furthermore, kinetic analyses were also achieved. The DNA photocleavage promoted by the title complex proceeds with a kobs of ~ 10.2 h− 1, a reaction rate useful in molecular biology practices, with a t1/2 of 4 min. This complex emerges as a new example of lanthanide compound with DNA cleavage ability by a non-hydrolytic mechanism.

Great efficiency in DNA cleavage promoted by Tb(tdzp)(acac)3 complex was achieved with UV-light illumination, without significant activity under dark conditions.Figure optionsDownload as PowerPoint slideHighlights
► The reported complex shows an efficient DNA cleavage activity under UV-A light.
► No activity was observed without UV-A light irradiation.
► During strand scission event radical species are produced.
► This complex is able to cleave DNA with a rate constant of 0.17 min− 1 which represents a half-life of only 4 min.