Application of boron-dopped diamond electrode for examination of electrochemical properties and quantity determination of daptomycin

In the presented master thesis study, a novel electrochemical method was developed for the determination of Daptomycin, a lipopeptide antibiotic whose clinical use has significantly increased in recent years. The method is based on the use of a boron-doped diamond (BDD) electrode, which was electrochemically activated in a sulfuric acid medium. Cyclic voltammetry (CV) measurements revealed that Daptomycin undergoes an irreversible oxidation process at approximately +1.05 V on the surface of the BDD electrode. For quantitative analysis, a linear calibration curve was obtained in the concentration range of 0.05–1.35 μg/mL using 0.5 M sulfuric acid as the supporting electrolyte. The resulting equation was Ip(μA) = 1.05 C[DAP] (μg/mL) + 0.096 with a high correlation coefficient (r = 0.995, n = 9). The limit of detection for the method was calculated as 0.01 μg/mL. The accuracy of the proposed method was evaluated by applying the standard addition–recovery approach to human urine samples. The analyses yielded an average recovery rate of 96.14% for Daptomycin.