Photoluminescence quenching of [Ru(bpy)2(atatp)]2 + bound to a condensed DNA matrix

• [Ru(bpy)2(atatp)]2 +-bound DNA film is prepared by a self-standing cast method.
• The stabilized DNA shows anti-oxidative activity against reactive oxygen species.
• Photoluminescence of the cast film is quenched by H2O, O2, [Fe(CN)6]4 − and Cu2 +.
• The proposed oxygen sensor has a wide linear range and high reproducibility.

A novel [Ru(bpy)2(atatp)]2 + (bpy = 2,2′-bipyridine and atatp = acenaphtheno[1,2-b]-1,4,8,9-tetraazatriphenylene) can induce the condensation of herring sperm DNA to form an orange-red cast film via intercalation and electrostatic attraction. The thus-prepared cast film shows microsecond emission lifetimes and reversible luminescence tuning characteristics by oxygen and nitrogen with an on–off emission intensity ratio of 4.3. The photoluminescence of [Ru(bpy)2(atatp)]2 + bound to a DNA condensed matrix can be quenched by water, dissolved oxygen, copper(II) and ferrocyanide ions. The DNA binding is found to hardly alter the dynamic quenching of [Ru(bpy)2(atatp)]2 + by oxygen at a low DNA-to-Ru(II) molar ratio (r = 0.83), allowing [Ru(bpy)2(atatp)]2 + to keep a basically unchanged oxygen quenching constant, as well as endow the photo-induced electron transfer between [Ru(bpy)2(atatp)]2 + and copper(II) cations, and weaken the electrostatic attraction of [Ru(bpy)2(atatp)]2 + with ferrocyanide anions. In addition, the DNA condensation induced by [Ru(bpy)2(atatp)]2 + can protect the DNA oxidative damage against superoxide anion and hydroxyl radical toxicity. The present results could provide a versatile platform for better fabrication of optoelectronic devices.

An acenaphthene-containing Ru(II) complex can induce the condensation of DNA to cast a uniform orange-red film, which shows reversible luminescence tuning characteristics by dissolved oxygen.Figure optionsDownload as PowerPoint slide