Highly sensitive and selective immunosensors are widely applied to detect small molecules. Organic solvents extraction of small molecules in samples is generally required when the small molecules have poor solubility in water. Immunosensing assays should tolerate at least some organic solvents to rapidly detect small molecules on-site. Herein, the effect of four organic solvents (methanol, acetone, acetonitrile, and n-hexane) on the homogenous and heterogeneous interactions between two small molecules (bisphonel A, BPA and aflatoxin M1, AFM1) and their respective antibodies was studied using an optofluidic immunosensing platform. To evaluate this influence on the immunoassay of small molecules, indirect competitive immunoassays of BPA and AFM1 were conducted under organic solvents of various concentrations. Antibody-antigen binding reaction and inhibition depends on the concentration and water-miscibility of organic solvents as well as chemical features. The homogenous or heterogeneous binding reaction of small molecules and their antibodies was nearly not influenced by water-immiscible n-hexane, even at a concentration of 40% (v/v). The quantitative immunoassay of small molecules could be carried out in water-miscible organic solvents of low concentration, including methanol, acetone, and acetonitrile. However, increasing the concentration of these organic solvents variably affects immunoassay of small molecules. The effect of the three water-miscible organic solvents with relatively high concentrations on the homogenous binding reaction is more significant than the heterogeneous binding reaction. The homogenous binding reaction between small molecules and their antibodies could be inhibited completely by acetone and acetonitrile solutions at high concentrations. The susceptibility of the binding reaction between different small molecules and their antibodies responded for different organic solvents vary. To rapidly detect small molecule on-site, an organic solvent should be carefully selected according to its extraction efficiency and effect on the immunoassay.

中文翻译：

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基于光流免疫传感平台的有机溶剂对小分子免疫检测的影响

高度灵敏和选择性的免疫传感器已广泛应用于检测小分子。当小分子在水中的溶解度较差时，通常需要有机溶剂萃取样品中的小分子。免疫传感测定法应至少能耐受某些有机溶剂，以便在现场快速检测出小分子。在本文中，使用光流体研究了四种有机溶剂（甲醇，丙酮，乙腈和正己烷）对两个小分子（双电话A，BPA和黄曲霉毒素M1，AFM1）与它们各自的抗体之间均相和异相相互作用的影响免疫传感平台。为了评估这种对小分子免疫测定的影响，在各种浓度的有机溶剂中进行了BPA和AFM1的间接竞争性免疫测定。抗体-抗原结合反应和抑制作用取决于有机溶剂的浓度和与水的混溶性以及化学特征。小分子及其抗体的同质或异质结合反应几乎不受水不混溶的正己烷的影响，即使浓度为40％（v / v）。小分子的定量免疫分析可以在低浓度的与水混溶的有机溶剂中进行，包括甲醇，丙酮和乙腈。但是，增加这些有机溶剂的浓度会影响小分子的免疫测定。三种相对较高浓度的可与水混溶的有机溶剂对均相结合反应的影响比均相结合反应更为显着。高浓度的丙酮和乙腈溶液可以完全抑制小分子与其抗体之间的均相结合反应。对于不同的有机溶剂，不同小分子与其抗体之间结合反应的敏感性不同。为了在现场快速检测小分子，应根据有机溶剂的提取效率和对免疫测定的影响精心选择有机溶剂。