Investigation of DOTA-Metal Chelation Effects on the Chemical Shift of (129) Xe

Chemphyschem. 2015 Dec 1;16(17):3573-7. doi: 10.1002/cphc.201500806. Epub 2015 Oct 7.

Abstract

Recent work has shown that xenon chemical shifts in cryptophane-cage sensors are affected when tethered chelators bind to metals. Here, we explore the xenon shifts in response to a wide range of metal ions binding to diastereomeric forms of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) linked to cryptophane-A. The shifts induced by the binding of Ca(2+) , Cu(2+) , Ce(3+) , Zn(2+) , Cd(2+) , Ni(2+) , Co(2+) , Cr(2+) , Fe(3+) , and Hg(2+) are distinct. In addition, the different responses of the diastereomers for the same metal ion indicate that shifts are affected by partial folding with a correlation between the expected coordination number of the metal in the DOTA complex and the chemical shift of (129) Xe. These sensors may be used to detect and quantify many important metal ions, and a better understanding of the basis for the induced shifts could enhance future designs.

Keywords: DOTA; NMR spectroscopy; cryptophane; metal-ion sensors; xenon.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Chelating Agents / chemistry*
  • Crystallography, X-Ray
  • Heterocyclic Compounds, 1-Ring / chemistry*
  • Metals, Alkaline Earth / chemistry*
  • Metals, Heavy / chemistry*
  • Models, Molecular
  • Molecular Structure
  • Xenon Isotopes / chemistry

Substances

  • Chelating Agents
  • Heterocyclic Compounds, 1-Ring
  • Metals, Alkaline Earth
  • Metals, Heavy
  • Xenon Isotopes
  • 1,4,7,10-tetraazacyclododecane- 1,4,7,10-tetraacetic acid