Spectroscopic investigation on the interaction of DNA with superparamagnetic iron oxide nanoparticles doped with chromene via dopamine as cross linker

The interaction of DNA with iron oxide nanoparticles (SPIONs) was studied to find out the interaction mechanism and design new drug delivery systems.
The interaction of calf thymus DNA (ctDNA) with SPIONs doped with 2H-chromene via dopamine as cross linker (SPIONs@DA-Chr) was studied using the UV absorption spectroscopy, viscosity measurement, circular dichroism, fluorescence and FT-IR spectroscopic techniques.
UV absorption study showed hyperchromic effect in the spectra of DNA. Few changes were observed in the viscosity of ctDNA in the presence of different concentration of SPIONs@DA-Chr. The result of circular dichroism (CD) suggested that SPIONs@DA-Chr can change the secondary structure of DNA. Further, fluorescence quenching reaction of ctDNA with SPIONs@DA-Chr and competitive fluorescence spectroscopy studied by using methylene blue, have shown that the SPIONs@DA-Chr can bind to ctDNA through non-intercalative mode. FT-IR spectroscopy confirmed the binding of SPIONs@DA-Chr and ctDNA.
These results suggested that SPIONs@DA-Chr binds to DNA via groove binding mode.