Differential Pulse Voltammetric Assay of Antibacterial Drug Doxycycline Hyclate

The electrochemical oxidation of Doxycycline Hyclate has been carried out in Britton - Robinson buffer at carbon paste and glassy carbon electrodes. Doxycycline Hyclate exhibits a well-defined irreversible oxidation peak in a broad pH range (2-11). Differential pulse voltammetry was used to determine Doxycycline Hyclate in pure form. The peak current varied linearly in the following ranges: 2.0×10-7- 3.0×10-6 mol L-1 and 2.0×10-7 - 2.6×10-6 mol L-1 in case of carbon paste electrode and glassy carbon electrode, respectively. In case of carbon paste electrode the limits of detection (LOD) and quantification (LOQ) were 6.56×10-8 mol L-1 and 2.19×10-7 mol L-1, respectively. For glassy carbon electrode the LOD and LOQ were 9.55×10-8 mol L-1 and 3.18×10-7 mol L-1, respectively. The percentage recoveries were found in the following ranges: 99.58-101.16% and 99.46-100.98% for carbon paste electrode and glassy carbon electrode, respectively. The relative standard deviations were found in the following ranges: 0.53-1.79% and 0.48-1.96% in case of carbon paste electrode and glassy carbon electrode, respectively. Differential pulse voltammetry was successfully applied for the determination of Doxycycline Hyclate in pharmaceutical form.