Electroanalytical sensing of antidiabetic drug linagliptin by using square-wave voltammetry on the boron-doped diamond electrode

This research paper presents an electroanalytical investigation utilizing voltammetry to quantify the antidiabetic drug linagliptin with an unmodified boron-doped diamond electrode. Using cyclic voltammetry, linagliptin exhibited a single, distinct, irreversible oxidation peak at around + 1.03 V (vs. Ag/AgCl) in a 0.1 mol dm⁻³ phosphate buffer solution at pH 7.4. The square-wave voltammetry technique achieved acceptable linearity at approximately + 0.94 V in PBS (pH 7.4). The methodology demonstrated linearity within the concentration range of 1.0 and 50.0 μg cm⁻³ (equivalent to 2.1 × 10^–6–1.1 × 10^–4 mol dm⁻³) and yielded a limit of detection of 0.28 μg cm⁻³ (equivalent to 5.9 × 10^–7 mol dm⁻³). The investigation of the proposed method's applicability was ultimately conducted through the sensing of linagliptin in drug formulations. The established methodologies can serve as viable alternatives to other analytical techniques due to their cost-effectiveness, user-friendliness, efficiency, and ability to yield reliable and repeatable results.

Graphical abstract