The way of immobilization of the monoclonal antibody (type IgG) on the electrode surface has a significant effect on the amount of the immobilized protein and in consequence on current signal of protein. Herein, we demonstrate that the application of appropriately functionalized phenyl film allowed us to control the orientation of the antibody (Ab) molecules on the electrode surface. The influence of Ab orientation on the efficiency of antigen-antibody interaction was tested with an example blood plasma protein (ferritin; Ft). To control the orientation of Ab molecules the phenyl films containing –COOH or –NH₂ groups were applied. Contrary to aminoethylophenyl layer, the carboxyphenyl film guaranteed the shortest distance between the redox center of the protein and the electrode surface. Additionally, the application of an external magnetic field together with magnetic nanoparticles allowed achieving the best orientation to observe well-defined ferritin current signals. The proposed method of ferritin detection can be successfully used in the concentration range of Ft between 0.1 and 30 µg dL⁻¹. The detection limit for a carboxyphenyl film was estimated as 0.40 ± 0.04 and 0.13 ± 0.04 µg dL⁻¹ for impedance and voltammetric measurements, respectively. In turn, for an aminoethylophenyl film the detection limit was 0.03 ± 0.002 (electrochemical impedance spectroscopy; EIS) and 0.02 ± 0.002 µg dL⁻¹ (differential pulse voltammetry, DPV). The interday precision (reproducibility) was calculated (4.10 ÷ 9.10% RSD) together with the intraday precision / repeatability (3.20 ÷ 8.0% RSD) for the studied samples. The functionality of the sensor has been tested on rat blood samples. Based on the performed investigations it can be stated that the developed sensor was characterized by high selectivity and good sensitivity.

将单克隆抗体（IgG型）固定在电极表面的方式对固定蛋白质的量有很大影响，因此对蛋白质的电流信号也有很大的影响。在此，我们证明了适当官能化的苯基膜的应用使我们能够控制电极表面上的抗体（Ab）分子的取向。用示例血浆蛋白（铁蛋白； Ft）测试了Ab取向对抗原-抗体相互作用效率的影响。为了控制Ab分子的取向，含–COOH或–NH ₂的苯基膜组被应用。与氨基乙基苯基层相反，羧基苯基薄膜可确保蛋白质氧化还原中心与电极表面之间的最短距离。另外，外部磁场与磁性纳米粒子的施加允许实现最佳取向，以观察明确定义的铁蛋白电流信号。所提出的铁蛋白检测方法可以在Ft的浓度范围介于0.1和30 µg dL ^-1之间成功使用。羧基苯基薄膜的检出限估计为0.40±0.04和0.13±0.04 µg dL ^-1分别用于阻抗和伏安测量。继而，对于氨基乙基苯基膜，检测极限为0.03±0.002（电化学阻抗谱； EIS）和0.02±0.002μgdL ^-1（差分脉冲伏安法，DPV）。计算出所研究样品的日间精度（可重复性）（4.1​​0÷9.10％RSD）以及日内精度/重复性（3.20÷8.0％RSD）。该传感器的功能已在大鼠血液样本上进行了测试。基于所进行的研究，可以说开发的传感器具有高选择性和良好灵敏度的特征。