SERS chiral recognition and quantification of enantiomers through cyclodextrin supramolecular complexation

Chemphyschem. 2011 Jun 6;12(8):1529-35. doi: 10.1002/cphc.201000800. Epub 2010 Dec 15.

Abstract

We introduce here a simple approach in which a cyclodextrin, functionalized with thiols in the narrower rim, is assembled onto the silver surface of a SERS platform composed of polystyrene beads coated with silver nanoparticles. Trapping properties of the fabricated sensor are demonstrated through the retention of different enantiomers (R,R or/and S,S) of hydrobenzoin (HBZ), a molecule that has not been reported before in SERS because it has no affinity for coinage metal surfaces. Further, selective recognition of each enantiomer and semiquantification of its proportion in a racemic mixture are provided by the analysis of the SERS spectra of the HBZ-cyclodextrin complex, in full agreement with the surface selection rules.