Voltammetric determination of captopril employing platinum electrode modified with iron (III) hexacyanoferrate (II) film

Environment contamination with drugs even at concentrations in the order mg L-1 and ng L-1 culminates in environmental and public health problems because these substances are biologically active. For this reason, the pursuit of instrumental methods for the determination of these substances has been the main target of several investigators. Captopril, an antihypertensive drug employed for the treatment of heart failure, has been identified by means of electrochemical technique. To this end, a platinum electrode modified with an iron (III) hexacyanoferrate (II) film (Prussian blue) associated with the cyclic voltammetry mode has been utilized. Our results have furnished a linear correlation coefficient (r) of 0.998 with a standard deviation (SD) of 0.007 μA, a detection limit (based on the 3 SD/m ratio) in 7 µmol L-1, and a quantification limit (based on the relationship 10 SD/m) of 23.3 µmol L-1.