Electrochemical studies of tamsulosin hydrochloride using multiwalled carbon nanotube-modified glassy carbon sensor

A differential pulse voltammetric sensor for the determination of tamsulosin hydrochloride (TAM) using multiwalled carbon nanotubes (MWNTs)-Nafion-modified glassy carbon electrode (GCE) has been developed. MWNTs were dispersed in water with the help of Nafion and were used to modify the surface of GCE via solvent evaporation. At MWNT-modified electrode, TAM gave a well-defined oxidation peak at a potential of 1084 mV in 0.1-M acetate buffer solution of pH 5. Compared to the bare electrode, the peak current of TAM showed a marked increase and the peak potential showed a negative deviation. The determination conditions, such as the amount of MWNT-Nafion suspension, pH of the supporting electrolyte and scan rate, were optimised. Under optimum conditions, the oxidation peak current was proportional to the concentration of TAM in the range 1 × 10^-3 M-3 × 10^-7 M with a detection limit of 9.8 × 10^-8 M. The developed sensor showed good stability, selectivity and was successfully used for the determination of TAM in pharmaceutical formulations and urine samples.