Plasmonic circular dichroism using Au fine particles and riboflavin

We report circular dichroism (CD) induced in the visible region using a composite film containing Au fine parti‐cles and riboflavin. It is revealed that binding of chiral molecules to the surface of Au fine particles is not necessary for the plasmon‐induced CD. Moreover, we find that composite films containing dye and glucose instead of Au fine particles and riboflavin induces a CD signal at the wavelength, where the dye shows an absorption peak. The polarity of the CD signal is reversed by using the enantiomer of glucose. Mechanism of the absorption‐induced CD in the visible region is discussed (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)