LAUSR

In this work, we investigated the electrochemical behavior of cisplatin at boron‐doped diamond (BDD) thin‐film electrodes using cyclic voltammetry. Flow injection analysis with amperometric detection (FIA‐EC) was used to determine the detection figures of merit. No electrode surface modification or conventional pretreatment was required to activate the BDD electrodes. Diffusion‐limited oxidation of cisplatin, dissolved in 0.1 M HClO4, occurred at 1.3 V (vs. Ag/AgCl (3M KCl)) in cyclic voltammetric measurements and at 1.5 V in hydrodynamic voltammetric measurements. FIA‐EC peak current responses were reproducible over 10 consecutive injections of 100 μM cisplatin (relative standard deviation (RSD) = 2.7%) at 1.5 V. The FIA‐EC peak current increased linearly with the cisplatin concentration from 1 to 100 μM (r2 = 0.988). The minimum detectable concentration was experimentally determined to be 0.5 μM (S/N = 3). Detection of cisplatin in spiked human urine was also investigated using FIA‐EC. Other electrochemically active species present in the urine specimen interfered with cisplatin detection at 1.5 V. These interferents were separated from cisplatin in the spiked urine specimen using solid‐phase extraction (SPE) sample pretreatment and ion exclusion chromatography. Both ultraviolet/visible (UV/Vis) and amperometric detection were compared. Cisplatin was detected 8.9 min after injection using a UV/Vis photodiode array (PDA) and 9.3 min after injection using BDD in an amperometric detector placed in series. Overall, BDD electrodes are a good choice for the reproducible and sensitive electrochemical detection of cisplatin using FIA‐EC or ion exclusion chromatography prior to amperometric detection. Ion exclusion chromatography (IEC) adds selectivity for the electrochemical detection of cisplatin in urine specimens.