Insight on metal ions inducing chiral self-assembly of DNA in silica mineralization

The self-assembly of DNA provides an attractive approach to understanding structural formation mechanism in living organisms and to assisting applications in materials chemistry. Herein, we investigated the effect of metal ions on chiral self-assembly of DNA through the synthesis of chiral mesostructured silica via self-assembly of metal ions, DNA, and silica source. 31 types of multivalent cationic metal ions were found to induce formation of chiral impeller-like DNA-silica complexes due to the chiral stacking of DNA. The strength of the interaction between the metal ion and phosphate group of DNA was speculated for the chiral stacking of DNA due to close distance of adjacent DNA to assure mutual recognition. Theoretical calculations indicated that chiral packing of DNA depends on the stability of the bridging phosphate-metal ion-phosphate bonds of DNA based on electron delocalization in d-orbital conjugation of metal ions.