DNA-modified carbon paste electrode applied to the study of interaction between rifampicin (RIF) and DNA in solution and at the electrode surface.

Rifampicin (RIF) is an antibiotic widely used against tuberculosis and a DNA intercalator. The interaction of RIF with double-stranded (ds) and single-stranded (ss) calf thymus DNA was studied in solution as well as at the electrode surface by means of transfer voltammetry using differential pulse as stripping mode with carbon paste electrode (CPE) at 0.2M acetate buffer at pH 5.0 and at 0.2M phosphate buffer pH 7.4. Differentiations in the above-mentioned interaction at different pH values are presented and compared in order to optimize the detection of Rifampicin (RIF).