Determination of Catechol Using Flow Injection -Electrochemical Detection with Banana Paste Electrode: Application to Adrenaline Determination


This work involves indirect determination of catechol compounds using flow-injection electrochemical detector. The detector based on the three-electrodes system, banana paste [which contained the polyphenyl oxidase (PPO) enzyme] as working electrode, auxiliary electrode Pt wire and silver/silver chloride, saturated potassium chloride Ag/AgCl .sat.KCl as reference electrode. The PPO enzyme in banana paste motivates the oxidation of the two hydroxyl groups in catechol to the o-quinone which is then reduced at(-0.65)V back to catechol. The reduction current was recorded and it is proportional to concentration of catechol. The technique has been applied to adrenaline hormone