Interaction of anticancer drug methotrexate with nucleic acids analyzed by multi-spectroscopic method

Methotrexate (MTX) as an antifolate, which is widely used as chemotherapeutic drugs. A high-dose MTX therapy has a direct toxicity influence on the non-germinal cells, especially the liver cells. It is known that the inject dose for adults is 10-36 mg and is half for children for routine use, while our experiments showed that the optimum dosage of MTX which enhanced the RLS intensities to the maximum is 4.54 ng ml(-1). The interaction of methotrexate (MTX)with nucleic acids in aqueous solution in the presence of cetyltrimethylammonium bromide (CTMAB), a kind of cationic surfactant similar to the Human cells, were investigated based on the measurements of resonance light scattering (RLS), UV-vis, fluorescence and NMR spectra, etc. The interaction has been proved to give a ternary complex of MTX-CTMAB-DNA in BR buffer (pH 9.30), which exhibits strong enhanced RLS signals at 339.5 nm. (C) 2008 Elsevier B.V. All rights reserved.