Nonhydrolytic sol–gel derived imprinted polymer–multiwalled carbon nanotubes composite fiber sensors for electrochemical sensing of uracil and 5-fluorouracil

The present work describes an exciting method for the generation of stable silica–molecularly imprinted polymer (MIP) composite fibers, via a non-hydrolytic sol–gel simple route, using carboxylated multiwalled carbon nanotubes. The modified MIP-composite fibers were used as an electrochemical sensor for the selective and sensitive analysis of ultra-trace level of 5-fluorouracil and uracil in aqueous, blood plasma, and pharmaceutical samples. Such sensors could be considered cost-effective, renewable, disposable, and reliable for in-field and clinical studies, without any cross-reactivity and matrix effect from real samples [limit of detection (3σ, aqueous solution); 1.30 ng mL−1, 5-fluorouracil and 0.56 ng mL−1, uracil].

► Generation of silica–MIP composite fibers, via a NHSG route, using MWCNTs-COOH. ► In situ synthesis of NHSG–MIP–MWCNTs composite via AGET-ATRP technique. ► Highly selective and sensitive analysis of Ura and 5-FU in real samples. ► Sensors are cost-effective, disposable, and reliable for in-field studies. ► LOD; 1.30 ng mL−1, 5-fluorouracil and 0.56 ng mL−1, uracil in aqueous medium.