Highly sensitive electrochemical sensor based on Pt nanoparticles/carbon nanohorns for simultaneous determination of morphine and MDMA in biological samples

Morphine and 3,4-methylenedioxymethamphetamine (MDMA or Ecstasy) are two majorly abused drugs worldwide, which are harmful to human health and social stability. Therefore, it is necessary to detection morphine and MDMA rapidly and sensitively. In this study, a highly sensitive electrochemical sensor for simultaneous determination of morphine and MDMA was developed based on high surface area carbon nanohorns decorated with Pt nanoparticles (CNHs@PtNPs). Under the optimized conditions, CNHs@PtNPs nanocomposite with three-dimensional structure exhibits good electrocatalytic activity toward morphine and MDMA. Differential pulse voltammetry peak currents increase linearly with analyte concentration. At the potential of 0.2 V and 1.0 V (vs. SCE), the fabricated electrode shows excellent sensing performance for morphine and MDMA with a wide linear range between 0.05 and 25.4 μmol L⁻¹, and detection limit of 0.02 μmol L⁻¹ and 0.018 μmol L⁻¹, respectively. Furthermore, the sensor exhibits good selectivity, repeatability and stability. Our developed method is also successfully applied to the highly sensitive determination of morphine and MDMA in human serum and urine samples with satisfactory results.