Electrochemical sensing of 5-fluorouracil by using graphyne coupled with carbon nanotube

5-Fluorouracil (FU), an uracil derivative, has emerged as a cornerstone chemotherapy agent for malignancies including esophageal cancer. Herein, we report the construction of a high-performance electrochemical sensor via modification of a glassy carbon electrode with a graphyne/carbon nanotube (GHY/CNT) nanocomposite. Operating in pH 7.0 phosphate buffer, this GHY/CNT sensor enables precise FU detection using differential pulse voltammetry. Critical operational parameters, including catalyst loading and supporting electrolyte pH as well as enrichment time, were systematically evaluated and optimized to enhance electrochemical responsiveness. Notably, the sensor exhibits robust anti-interference capacity, maintaining stable performance even in the presence of common interfering substances. Under optimal conditions, the sensor demonstrates a wide linear response range (0.01 – 16 µM) to FU concentrations, coupled with a low detection limit (2 nM). When applied to human urine sample analysis, the sensor yields satisfactory recovery rates, validating its real-world applicability. Collectively, the GHY/CNT-based sensor showcases exceptional sensitivity, repeatability, reproducibility, and stability, highlighting its promising potential for clinical FU monitoring.