Novel screen-printed sensors with chemically deposited boron-doped diamond and their use for voltammetric determination of attention deficit hyperactivity disorder medication atomoxetine

Abstract

A novel lab-made disposable screen-printed sensor with chemically deposited boron-doped diamond (LM-SP/BDDE) was characterized by scanning electron microscopy (SEM), Raman spectroscopy, and compared to bulk boron-doped diamond electrode (BDDE) and commercially available screen-printed sensor with BDD working electrode (SP/BDDE). The sensors were applied for the determination of atomoxetine (ATX), a pharmaceutically active ingredient used to treat symptoms of attention deficit hyperactivity disorder (ADHD). Using bulk BDDE and a newly developed differential pulse voltammetric (DPV) method with optimized pre-treatment, DPV parameters, and in Britton-Robinson buffer of pH 2, obtained limit of detection (LOD) was 3.7×10−8 mol L−1. Subsequently, this new method was successfully transferred to the tested SP/BDDE sensors and verified on analysis of an ATX-containing drug Strattera 60MG with excellent repeatability (relative standard deviation (RSD) < 2.5% (n = 5)). Moreover, elimination voltammetry with linear scan (EVLS) uncovered multiple (3-5) diffusion-controlled irreversible oxidation steps at all tested sensors.