Electrochemical determination of prolintane in pharmaceutical formulations and in human urine

The oxidative behavior of 1‐[1‐(phenylmethyl)butyl]pyrrolidine, prolintane, was studied at a glassy carbon electrode using linear‐sweep and differential‐pulse voltammetry. The oxidation process was shown to be irreversible using 0.04 M Britton–Robinson buffer and was diffusion‐adsorption controlled. Two voltammetric methods were developed for the determination of prolintane using different techniques: linear‐sweep and differential‐pulse voltammetry. The peak current varied linearly with prolintane concentrations in the range of 1.0 × 10 −5 −2.5 × 10 −4 M, with a detection limit of 8.5 × 10 −6 and 4.0 × 10 −6 M, and with relative standard deviations of 2.1 % and 3.1 %, respectively. The methods were applied to commercial preparations, giving relative errors less than 3.1 % and relative standard deviations lower than 4.8 % ( n = 10). Determination of prolintane (down to the 8.5 × 10 −8 M level) can be performed by using a preconcentration step prior to the determination by differential‐pulse voltammetry in 0.04 M Britton–Robinson buffer (pH 8.0) with preconcentration potential of 0.0 V. The detection limit was found to be 6.2 × 10 −8 M (4 min preconcentration) and the relative standard deviation for 2.5 × 10 −7 M prolintane ( n = 5) was 4.6 %. Applicability to human urine analysis is illustrated (recovery 98 ± 2 %). Standard additions method can be used to determine prolintane in real samples of urine.