Surface‐enhanced resonance raman spectroscopy of hypericin and emodin on silver colloids: SERRS and NIR FTSERS study

Abstract

Abstract SERS, SERRS and NIR FTSERS of emodin and hypericin are reported for the first time on aqueous silver colloid. Intense SERRS spectra can be obtained when using excitation lines at 514 nm for emodin and 598 nm for hypericin. FTIR and NIR FTRaman spectra from these molecules and their model compounds, anthrone and bianthrone, were recorded to assist in the assignment of the SERS bands. From the analysis of the SERS spectra a different orientation for each molecule can be deduced. © 1995 John Wiley & Sons, Inc.