Hematite nanoparticle decorated MIL-100 for the highly selective and sensitive electrochemical detection of trace-level paraquat in milk and honey

An octahedral metal-organic framework, MIL-100, was synthesized by a hydrothermal method followed by high-temperature calcination. Thereafter, hematite nanoparticles were assembled on its surface to form Fe2O3-MIL-100, which was used to develop an electrochemical sensor for the sensitive detection of paraquat (PQ). The Fe2O3-MIL-100-based electrochemical sensor showed appreciable sensing performance under optimized conditions, with a linear response in the range of 0.01–30 μM and a limit of detection of 2.6 nM. The Fe2O3-MIL-100-based electrode produced an excellent current response to PQ even after 20 d of storage. Notably, the Fe2O3-MIL-100-based electrochemical sensor exhibited high sensitivity and selectivity for PQ detection in milk and honey samples. Therefore, the fabricated sensor can be an effective tool for the rapid detection of PQ in foods.