Induced chiroptical properties of helical Eu(iii) complex by electrostatic interaction with DNA

Abstract

Circularly polarized luminescence (CPL) has significantly increased the interest in biological fields. In this research, a water-soluble Eu(III) complex with a helical complex structure, EuL^COOH, was incorporated in chiral DNA in aqueous solutions. The photoluminescence performance of this DNA/EuL^COOH hybrid system was investigated. Compared to EuL^COOH alone, emission intensity and emission lifetime were effectively improved in the presence of DNA. The major binding between EuL^COOH and DNA was proven to be the electrostatic interaction. Owing to this interaction, the chiral environment provided by DNA successfully induced CPL from EuL^COOH.