Abstract
The interaction of anticancer drug hypocrellin B (HB) and mono-cysteine substituted hypocrellin B (MCHB) with calf thymus deoxyribonucleic acid (CT-DNA) has been investigated using spectral methods. The results of UV–visible spectra showed that the HB and MCHB can intercalate into the base-stacking domain of the CT-DNA double helix. Further studies based on fluorescence spectroscopy and circular dichroism (CD) spectroscopy also supported the intercalation mechanism.