Dual Esterase- and Steroid-Responsive Energy Transfer Modulation of Ruthenium(II) and Rhenium(I) Complex Functionalized Gold Nanoparticles

Frankie Chi-Ming Leung; Vonika Ka-Man Au; Hai-Ou Song; Vivian Wing-Wah Yam

doi:10.1002/chem.201501808

Dual Esterase- and Steroid-Responsive Energy Transfer Modulation of Ruthenium(II) and Rhenium(I) Complex Functionalized Gold Nanoparticles

Chemistry. 2015 Nov 9;21(46):16448-54. doi: 10.1002/chem.201501808. Epub 2015 Sep 23.

Authors

Frankie Chi-Ming Leung¹, Vonika Ka-Man Au¹, Hai-Ou Song¹, Vivian Wing-Wah Yam²

Affiliations

¹ Institute of Molecular Functional Materials and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR (P. R. China).
² Institute of Molecular Functional Materials and Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong SAR (P. R. China). wwyam@hku.hk.

PMID: 26395881
DOI: 10.1002/chem.201501808

Abstract

A number of adamantane-containing ruthenium(II) and rhenium(I) complexes have been synthesized, characterized, and noncovalently functionalized with β-cyclodextrin-capped gold nanoparticles (β-CD-GNPs) through the host-guest interaction between cyclodextrin and adamantane. The resultant nanoconjugates have been characterized by transmission electron microscopy (TEM), energy-dispersive X-ray analysis (EDX), and 2D ROESY (1) H NMR experiments. The Förster resonance energy transfer (FRET) properties of the nanoconjugates can be modulated by both esterase-accelerated hydrolysis and competitive displacement of steroid, by monitoring the emission intensity and luminescence lifetime. The FRET efficiencies are found to vary with the nature of the chromophores and the length of the spacer between the transition metal complexes and the GNPs. This work constitutes a "proof-of-principle" assay method for the dual-functional detection of important classes of biomolecules, such as enzymes and steroids.

Keywords: esterase; gold nanoparticles; rhenium; ruthenium; steroids.