Ultra-sensitive determination of serotonergic antidepressant vortioxetine in pharmaceutical and blood samples at the boron-doped diamond electrode

In this work, an ultra-sensitive voltammetric method for the determination of serotonergic antidepressant vortioxetine (VTX) was developed using an anodically pretreated boron-doped diamond electrode and square-wave voltammetry (SWV). In this modification-free platform, VTX was irreversibly oxidized at 1.09 V (vs. Ag/AgCl (3.0 mol/L KCl)) in Britton-Robinson buffer solution (pH 4.0). Under optimized instrumental parameters of SWV, the oxidation current of VTX increased linearly in the concentration range of 9.99 - 148 nmol/L, obtaining a limit of detection of 2.35 nmol/L. The method was successfully applied to commercially available Brintellix (R) tablets, and the results obtained were statistically similar to those obtained by a spectrophotometric method. Additionally, the simultaneous determination of VTX and amiloride was demonstrated and applied in blood rat serum. The method proved not to suffer from matrix interference providing excellent recoveries.