Figure 2. Magnetization of the copper ion modified DNA thin films.

(a) The variation of magnetic moment with magnetic field, m-H for piranha- treated glass (PG), 5 mM [Cu²⁺] in 1 × TAE/Mg²⁺ without DNA on PG (Cu Only) and various [Cu²⁺] DNA complexes. (b) The M-H curves for 5 mM [Cu²⁺] alone (Cu Only) and inset showing the pristine PG substrate. (c) M-H curves for various [Cu²⁺] used in the DNA thin films (the values shown are with the m values of PG subtracted) with ion concentrations 0, 3, 5, 10 and 20 mM marked as Cu0, Cu3, Cu5, Cu10 and Cu20 respectively.