Electrochemical Behavior of Neratinib at a Boron-Doped Diamond Electrode: Role of Tween 20 in Interfacial Signal Enhancement.

Neratinib (NER) is an irreversible tyrosine kinase inhibitor employed in the therapy of HER2-positive breast cancer. In the present research, the electrochemical oxidation of NER at a boron-doped diamond electrode (BDDE) was surveyed with particular emphasis on the act of surfactant-mediated interfacial influences. Cyclic and differential pulse voltammetry were used to characterize the oxidation behavior of NER and to establish an analytical approach for its determination. Among the explored anionic, cationic, and nonionic surfactant species, Tween 20 produced the most proper electrochemical reply, obviously augmenting the anodic peak current and improving signal stability. Electrochemical impedance spectroscopy (EIS) further represented that Tween 20 considerably revised the electrolyte/BDDE interface, increasing the charge-transfer resistance of the ferri/ferrocyanide redox probe from 510 to 1822 Ω. Importantly, this increment in interfacial resistance comprised concurrently with enhancement of the NER voltammetric response, indicating that Tween 20 does not act through a nonspecific acceleration of electron-transfer kinetics. Conversely, the monitored signal enhancement is consistent with affirmative NER-surfactant interplays and a modified interfacial microenvironment that assists the electrochemical accessibility of NER. Scan-rate and pH-dependent investigations defined that NER undergoes an irreversible, predominantly diffusion-controlled oxidation involving proton-coupled electron transfer. Under the optimized experimental conditions at pH 7.02 containing 100 μM Tween 20, the DPV signal was linear the NER concentration between 0.03-1.50 μM (16.7-836 ng mL