A cyclic voltammetric study on the electrochemical behavior and endurance of pyridoxine at cobalt hexacyanoferrate based carbon paste sensor in local available vitamin-B6 medications.

Cyclic voltammetric technique was used to study the electrochemical behavior of pyridoxine on surface ofcobalt hexacyanoferrate based carbon paste electrode in phosphate buffer solution of pH 6 at a scan rate 100mV/s. The voltametric parameters and experimental conditions were optimized for present study. On application of this sensor instead of bare carbon paste sensor, the oxidation peak current signal of pyridoxine indicated significant increase from 82.96 ?A to 343.2 ?A. The effects of pH and impurities of solutions on electrochemical characteristics of chemically improved sensor were studied. The magnitude of electrochemical parameters like current density ratio (ipa/ipc=1.31) and increasing peak potential’s gap (Epa- Epc) with rising analyte concentration as well as applied scan rate, predicted the irreversibility of the redox process, involving transfer of two electrons (pH effect) at interface. The effect of scan rate showed that the electrode process was both diffusion and adsorption controlled. The relationship between anodic peak current density and analyte concentration (5.0 ?M to 26.0 ?M) was found linear with a correlation coefficient, ‘R’=0.9998 (n =10) and a standard deviation ‘S’ = 0.01535. The linear regression equation was found as “ip (?A) = 0.09668C (?M) + 1.04561”.The detection and quantification limits were found 4.8 × 10?7M and 1.56 x 10-6 M by this method, respectively. The recovery results determined by the application of analytical standard curve using the non-spiked and the spiked sample solutions of locally available vitamine-B6 medicines were found in good agreement to that of recent reported literature values for pyridoxine, cyclicvoltametrically. Interference studies suggested an excellent selectivity of the proposed method toward vitamine-B6.