Computational chemistry-based hapten design and antibody production for the immunochromatographic assay of maleic hydrazide in food and environmental samples

Maleic hydrazide (MH), a selective herbicide and plant growth inhibitor, poses risks to ecological balance and human health due to its widespread use. In this study, we developed a simple, reliable, and rapid detection method for MH. Four haptens were analyzed using computational chemistry simulations, and a matrix effect-enhanced screening method was used to obtain the anti-MH monoclonal antibody, with a half-maximal inhibitory concentration (IC₅₀) of 0.157 μg/mL. An immunochromatographic assay was developed for detecting MH in lake water, soil, onion, garlic, potato, and tobacco samples. The IC₅₀ values ranged from 0.590 to 9.419 mg/kg, with a detection limit of 0.047–1.614 mg/kg. Spiked recovery and real sample analyses demonstrated results consistent with instrumental methods, achieving recoveries of 89.2 %–111.3 % and CV < 7 %. These findings confirm the method's suitability for detecting MH in food and environmental samples, fulfilling the requirements for on-site rapid detection in resource-limited settings.