TY - JOUR

T1 - Ag−DNA Emitter: Metal Nanorod or Supramolecular Complex?

AU - Ramazanov, Ruslan R.

AU - Sych, Tomash S.

AU - Reveguk, Zakhar V.

AU - Maksimov, Dmitriy A.

AU - Vdovichev, Artem A.

AU - Kononov, Alexei I.

PY - 2016

Y1 - 2016

N2 - Ligand-stabilized luminescent metal clusters, in particular, DNA-based Ag clusters, are now employed in a host of applications such as sensing and bioimaging. Despite their utility, the nature of their excited states as well as detailed structures of the luminescent metal–ligand complexes remain poorly understood. We apply a new joint experimental and theoretical approach based on QM/MM-MD simulations of the fluorescence excitation spectra for three Ag clusters synthesized on a 12-mer DNA. Contrary to a previously proposed “rod-like” model, our results show that (1) three to four Ag atoms suffice to form a partially oxidized nanocluster emitting in visible range; (2) charge transfer from Ag cluster to DNA contributes to the excited states of the complexes; and (3) excitation spectra of the clusters are strongly affected by the bonding of Ag atoms to DNA bases. The presented approach can also provide a practical way to determine the structure and properties of other luminescent metal clusters.

AB - Ligand-stabilized luminescent metal clusters, in particular, DNA-based Ag clusters, are now employed in a host of applications such as sensing and bioimaging. Despite their utility, the nature of their excited states as well as detailed structures of the luminescent metal–ligand complexes remain poorly understood. We apply a new joint experimental and theoretical approach based on QM/MM-MD simulations of the fluorescence excitation spectra for three Ag clusters synthesized on a 12-mer DNA. Contrary to a previously proposed “rod-like” model, our results show that (1) three to four Ag atoms suffice to form a partially oxidized nanocluster emitting in visible range; (2) charge transfer from Ag cluster to DNA contributes to the excited states of the complexes; and (3) excitation spectra of the clusters are strongly affected by the bonding of Ag atoms to DNA bases. The presented approach can also provide a practical way to determine the structure and properties of other luminescent metal clusters.

U2 - 10.1021/acs.jpclett.6b01672

DO - 10.1021/acs.jpclett.6b01672

M3 - Article

VL - 7

SP - 3560−3566

JO - Journal of Physical Chemistry Letters

JF - Journal of Physical Chemistry Letters

SN - 1948-7185

IS - 18

ER -