SURFACE-ENHANCED RAMAN-SPECTROSCOPIC STUDY OF AMSACRINE AND AMSACRINE DNA INTERACTIONS

Surface-enhanced Raman scattering (SERS) spectroscopy has been employed to study the interaction of intercalating ligands with DNA. SERS was used to obtain spectra of acridine, aminoacridine, the 9-anilinoacridine amsacrine and related compounds at associated solution concentrations down to 1-mu-M. A major advantage of SERS was the near absence of fluorescence normally inherent in solution spectra of these compounds. SERS spectra of amsacrine-DNA complexes at various ligand/base pair ratios showed free ligand concentrations consistent with those calculated from the binding constant, and showed that the less strongly interacting acridine was largely unbound even at high ligand/base pair ratios.