a sensitive electrochemical dna biosensor for determination of capecitabine anticancer drug based on ss-dna/rgo/mos2/carbon paste electrode

The present research utilized a simplified procedure for developing a novel electrochemical sensor based on a carbon paste electrode (cpe) modified with single-stranded dna (ss-dna), reduced graphene oxide and molybdenum disulfide. unmodified (bare cpe) and modified (ss-dna/rgo/mos2/cpe) electrodes were characterized by scanning electron microscopy (sem), edx analysis and cyclic voltammetry (cv). characterization data confirm the good conductivity and electrocatalytic nature with more electrochemically active sites in ss-dna/rgo/mos2/cpe compared to bare cpe in determination of capecitabine (cap) analysis in real samples. two linear ranges have been obtained for the cap concentration within the ranges of 0.01-10 μm with and 10-60 μm, with a detection limit of 0.0108 μm and limit of quantification of 0.036 μm. lower linear concentration range, 0.01-10 μm showed sensitivity of 276.85 am-1cm-2, and another from 10 μm to 60 μm with a sensitivity of 5.88 am-1cm-2. the performance of the modified electrode was tested in human serum samples and obtained satisfactory recovery results. the selectivity and practical ability of ss-dna/rgo/mos2/cpe to determine cap in the presence of different interfering species were investigated. the results show the selective, reliable and accurate response of ss-dna/rgo/mos2/cpe as cap electrochemical sensor.