本项目提出了一种食品中微量蛋白质的高灵敏阻抗免疫检测新方法。该方法首先利用带有一抗的免疫磁球在样本中对被测物进行捕捉，然后进行磁分离，之后在外加磁场作用下，在带有检测抗体的电极表面快速富集磁球并进行免疫反应，最后利用磁球的几何尺寸，采用简便、稳定的阻抗法进行高灵敏检测。项目研究的具体内容包括：1）微纳磁球的电频谱特性；2）不同磁球在外加磁场作用下运动及对免疫反应影响的建模研究；3）阻抗测量结构的优化；4）过敏原多目标筛查阵列等。该方法能够对复杂食品样本进行有效预处理富集，具有磁球免疫反应速度快、阻抗检测灵敏度高、装置简单、检测结果稳定、易定量等优点，能够满足食品快速检测筛查的需要。在项目的实施过程中，选用越来越引起人们关注的食物过敏原（卵白蛋白等）作为检测目标。同时，该方法也可以方便地拓展到食品样本中其他大分子蛋白的检测中去。根据我们的了解，目前国内外还未有相似方法的研究报道。

In this project we propose a novel impedimetric immunoassay method for the detection of trace proteins in food samples. In this approach, firstly the target proteins in the sample are captured on the magnetic beads with antigen/antibody reaction. Then, under the effect of external magnet, the magnetic beads are enriched on the electrode surface through the second antibody which is immobilised on the electrode. Finally, impedimetric measurement is employed to determine the concentration of magnetic beads, which is related to the concentration of target protein in the sample. In this project, we will investigate 1) the electrical frequency properties of micro/nano magnetic beads; 2) modelling the movements of magnetic beads under the effect of external magnetic field; 3) the optimization of impedance measuring structure; 4) the screening of multi-allergens in the sample through impedimetric array. This method is capable of handling complex food samples. And it has the advantages such as short response time, high sensitivity, and simple measurement setup, which facilitates its applications on rapid screening of food samples. In this project, food allergen (ovalbumin etc.) is selected as detection target. At the same time, this method can also be easily extended to the detection of other macromolecular proteins in food samples. To our knowledge, there is no report of such method in the literatures up to now.