An electrochemical and theoretical approach for the development of a sensitive flower-like nanosensor as serotonin receptor antagonist tropisetron

Abstract Tropisetron (TRP) is a first-generation serotonin (5-hydroxytryptamine or 5-HT) receptor antagonist with antiemetic properties that are primarily used to prevent chemotherapy-induced nausea and vomiting. An ultrasensitive electrochemical nanosensor was developed by using surfactant 1-(2,4-dinitrophenyl)-dodecanoylthiourea (DAN) along with ZnO as a modifier on the screen-printed electrode (SPE) for the picomolar detection of TRP. The proposed nanosensor for TRP detection was characterized by electrochemical techniques such as impedance spectroscopy, cyclic voltammetry (CV), and square wave voltammetry (SWV). For optimization, the effect of several factors such as scan rate, the concentration of the modifier, accumulation time, pH, supporting electrolytes, and deposition potential was investigated. The limit of detection was found to be 84 pM using DAN/ZnO/SPE. Reasonable percentage recoveries for the human serum sample analysis with less than 2.0 % RSD values validated the proposed nanosensor. Furthermore, the designed nanosensor showed exceptional stability, sensitivity, accuracy, and reproducibility, suggesting our proposed nanosensor's potential candidature for detecting TRP in working samples. The interaction between the modified electrode surface and TRP was discussed with the quantum chemical parameters obtained using the density functional theory (DFT).