Electrochemical Determination of Natural Drug Colchicine in Pharmaceuticals and Human Serum Sample and its Interaction with DNA

Colchicine (COLC) is a natural toxic product and secondary metabolite most commonly used to treat gout. In this study, its electrochemical behavior and determination was investigated by employing modification-free boron-doped diamond electrode (BDDE). Besides, its interaction with DNA was monitored using electrochemical methods. It was found that oxidation of this compound proceeds in two steps, where first sharp and well defined oxidation peak occurs at potential of around 1.19 V, and second one at around 1.37 V, in Britton-Robinson buffer solution at pH 7.5. Wide dynamic range from 1 to 100 μM was obtained with a detection limit (3σintercept/slope) of a 0.26 μM, based on the evaluation of first oxidation peak using differential pulse voltammetry. The proposed method was also found to be suitable for monitoring interaction of this drug with DNA as important segment for medical use. Concerning the validation, the analytical procedure shows excellent selectivity and sensitivity toward COLC detection and after method development it was successfully used for its quantification in pharmaceutical preparation and human serum sample, with satisfactory recovery. Obviously, this approach can be promising replacement for time-consuming and expensive separation methods.