Electrochemical behavior study and determination of isoniazidon the solgel electrode modified with carbon nanotubes

Isoniazid is considered as the first choice for treatment and recovery of phthisis diseases. The phthisis diseases are contagious and known as the main reason of human death in all over theworld. Therefore, determination of isoniazid, the Anti-T B drug, as first-line TB drugs and the main treatment regimen for tuberculosis in all over the world can be very valuable [1-2]. Therefore, design and development of a sensor with the aim of isoniazid determination can bevaluable in order to determination of this important material. However, electro oxidation of isoniazid on bare electrodes needs high over potentials and is kinetically slow. Therefore, various modified electrodes with the aim of improvement of the rate of electron transfer and overpotentialreducing were introduced. In modified electrodes, the surface of conventional electrodes were covered with thin layer of a chemical compounds, which cause in change in properties of electrode surface and electrochemical behavior of electro-active compounds [3].Recently carbon nanotubes have attracted more attention in chemistry specially in electroanalytical chemistry. Carbon nanotubes are unique tubular structures with diameter on nanometerand high ratio of length to width [4]. Because of high chemical stability, high surface area, unique electronic and mechanical properties, carbon nanotubes have attracted much attention. Carbon nanotubes could be act as electron transfer mediator between electro-active species andelectrode surface and therefore created a new approach for construction of sensors and biosensors [5]. In this study, the electrochemical behavior of isoniazid at a carbon nano tube modified sol-gel electrode has been studied using cyclic voltammetry and differential pulse voltammetrictechniques. High sensivity and diminution of the overpotential for isoniazid oxidation at nanotube modified sol-gel electrode a carbon is the main advantage of designed sensor.The numerous factors affecting the oxidation peak currents of isoniazid electrode were optimized to maximize the sensitivity. The modified electrode presented a linear response range for isoniazid from 0.05 to 1.8 mM, from 1 to 70 μM with detection limits8.58 μM and 0.13μM for Cyclic voltammetry and differential pulse voltammetry respectively. The results showed that themodified electrode has very high catalytic ability for electro oxidation of isoniazid. In addition, thise proposed modified electrode exhibited excellent sensitivity, reproducibility and stability. Moreover, the modified electrode wase used for determination of isoniazid in tablets and spikedserum as real sample.

کلیدواژه ها:

Isoniazid ، Sol – gel ، Modified electrode ، Carbon nanotubes