Voltammetric Characterization and Quantification of the Cocaine Analog Nitracaine

Abstract

Synthetic cocaine analogs are designer drugs that recently emerged as non-controlled substitutes for their parent drug. Among them, nitracaine is of particular concern for its psychoactive effect. In this work, we present a thorough characterization of the electrochemical behavior of nitracaine, with a final quantification performed by differential pulse voltammetry (DPV) in ethanol/lithium perchlorate 0.1 M. The selectivity of the method and reproducibility of results were assessed. LOQ of 0.3 μg mL⁻¹ and a linear dynamic range of up to 400 μg mL⁻¹ were obtained. In addition, recoveries from 85 % to 101 % were achieved on both simulated and real samples. For nitracaine analysis in urine, a clean-up and a preconcentration step by solid phase extraction (SPE) using the adsorbent Florisil have been developed and optimized through the Design of Experiments (DoE) strategy, thus achieving an enrichment factor of 20.