Direct detection of ethyl carbamate in baijiu by molecularly imprinted electrochemical sensors based on perovskite and graphene oxide

Ethyl carbamate (EC), a carcinogen commonly found in Baijiu, requires an efficient detection method for quality control and monitoring. This study introduces a novel molecularly imprinted electrochemical sensor for sensitive and selective EC detection. We proposed a simple sol-gel method for the growth of perovskite-structured lanthanum manganate (LaMnO₃) on graphene oxide (GO). A non-enzymatic electrochemical sensor was developed by coating a molecularly imprinted polymer synthesized via precipitation polymerization onto the surface of LaMnO₃@GO. LaMnO₃, with its superior three-dimensional nanocube structure, demonstrated excellent electrocatalytic activity, while the addition of GO provided a large specific surface area. The results indicate that the developed sensor exhibits exceptional recognition ability and electrochemical activity, which is attributed to the high affinity of LaMnO₃@GO@MIP for EC. The sensor displays a broad linear range from 10 to 2000 μM, with a detection limit as low as 2.18 μM and long-term durability of 28 days. Notably, it demonstrates excellent selectivity, reproducibility, and stability even under different interference conditions. The sensor was successfully used to determine EC in real Baijiu samples. Overall, the sensor has broad application prospects for detecting trace contaminants in the field of food safety.