Immunoassays are nowadays being employed for rapid contaminant analysis in clinical, environmental, and agrochemical samples. A thorough characterization of the antibody‒antigen interaction can bring light to the immunoreagent selection process in order to develop sensitive and robust tests. Thus, determination of equilibrium and reaction rate constants is usually recommendable. However, this can be quite tricky for low molecular weight compounds, and competitive strategies are commonly followed to estimate apparent affinity values. In the present study, a collection of monoclonal antibodies to penthiopyrad was raised for the first time, and apparent equilibrium constants were assessed by the Langmuir model using three different competitive enzyme-linked immunosorbent assay formats. The obtained K_D values from antibody-coated assays were quite close to the corresponding K_D values calculated from surface plasmon resonance (SPR) evaluation. These studies were employed to select a pair of immunoreagents for immunoassay development. The K_D value for penthiopyrad of the selected antibody obtained by SPR was 0.28 nM. The optimized direct assay showed an IC₅₀ value for penthiopyrad of 0.42 nM (0.15 ng mL⁻¹) in buffer. The limit of quantification for grape, must, and wine samples was 10 ng mL⁻¹. An excellent correlation was found when immunochemical results were compared with those from LC-MS/MS. As an application case, it was determined that 58% of penthiopyrad was still found in wine after fermentation.

如今，免疫分析已用于临床，环境和农业化学样品中的快速污染物分析。抗体与抗原相互作用的全面表征可以为免疫试剂选择过程带来启发，从而开发出灵敏而强大的测试方法。因此，通常建议确定平衡和反应速率常数。然而，这对于低分子量化合物而言可能非常棘手，并且通常遵循竞争策略来估计表观亲和力值。在本研究中，首次提出了针对戊硫吡喃的单克隆抗体，并通过Langmuir模型使用三种不同的竞争性酶联免疫吸附测定形式评估了表观平衡常数。获得的K _D抗体包被的检测值与表面等离振子共振（SPR）评估计算得出的相应K _D值非常接近。这些研究被用于选择一对用于免疫测定开发的免疫试剂。通过SPR获得的所选抗体的戊硫吡喃酮的K _D值为0.28 nM。优化的直接分析显示在缓冲液中戊硫吡thio的IC ₅₀值为0.42 nM（0.15 ng mL ^-1）。葡萄，葡萄汁和葡萄酒样品的定量极限为10 ng mL ^-1。当将免疫化学结果与LC-MS / MS的结果进行比较时，发现了极好的相关性。作为一个应用案例，确定发酵后的葡萄酒中仍发现58％的戊硫吡喃。