Paclobutrazol (PBZ) is a plant growth regulator (PGR) widely used in fruit and vegetable cultivation. However, due to the severe toxicity of PBZ, a sub-ppm level maximum residue limit (MRL) was established worldwide. Therefore, it is significant to propose a rapid, sensitive and high throughput screening method for monitoring the PBZ residues in foods. In this study, a simple and sensitive indirect competitive Enzyme-linked immunosorbent assay (icELISA) was established for PBZ detection in fruits basing polyclonal antibody. For both economy and pollution prevention, a microwave-solvent-free method was used to synthesize the PBZ hapten with high efficiency. The detection conditions, such as coating antigen concentration, antibody concentration, organic reagent concentration, ionic strength and pH, were optimized. Under the optimized conditions, this method showed high sensitivity and specificity. The detection range is 1.27-138.23 ng/mL, half-maximum inhibition concentration (IC50) is 13.26 ng/mL, and the IC20 was lower than the reported ELISAs for PBZ. Additionally, this method had high accuracy and precision. The recoveries were ranged from 88.78% to 96.80% in PBZ spiked apple samples with RSD below 4%. All the results showed that the polyclonal antibody based icELISA could be useful for PBZ screening in fruit samples.

中文翻译：

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基于多克隆抗体的间接竞争酶联免疫吸附测定法，用于筛选水果中的多效唑。

多效唑（PBZ）是一种植物生长调节剂（PGR），广泛用于水果和蔬菜种植。但是，由于PBZ的严重毒性，因此在全球范围内建立了低于ppm级的最大残留限量（MRL）。因此，重要的是提出一种快速，灵敏和高通量的筛选方法，以监测食品中的PBZ残留。在这项研究中，建立了一种简单，灵敏的间接竞争性酶联免疫吸附测定法（icELISA），用于基于多克隆抗体的水果中PBZ检测。为了经济和防止污染，使用无微波溶剂的方法高效地合成了PBZ半抗原。优化了检测条件，如包被抗原浓度，抗体浓度，有机试剂浓度，离子强度和pH。在优化条件下 该方法显示出高灵敏度和特异性。检测范围为1.27-138.23 ng / mL，半最大抑制浓度（IC50）为13.26 ng / mL，IC20低于已报道的PBZ ELISA。另外，该方法具有较高的准确性和精度。在RSD低于4％的PBZ加标苹果样品中，回收率的范围为88.78％至96.80％。所有结果表明，基于多克隆抗体的icELISA可用于水果样品中的PBZ筛选。