The voltammetric behaviour of methylated guanine-MeGua-(1-methylguanine, 3-methylguanine, 7-methylguanine and 9-methylguanine) was investigated over a wide pH range by using differential pulse cathodic stripping voltammetry at hanging mercury drop electrode. Methylated guanine as well as guanine are weakly interacted with mercury, but in presence of copper ions (5.0 × 10−7 M) they adsorb at a HMDE to give one stripping peak. This peak appears to be due to adsorption of MeGua-Cu(I) complex. The dependence of the stripping peak on the various experimental conditions is considered.
Cathodic stripping behaviour suggests that MeGua can be determined by cathodic stripping voltammetry in presence of Cu(II) ions and their detection limits are comparable to those for guanine.