The use of green-synthesized Fe₃O₄/Ag composites nanoparticles (NPs) on the surface plasmon resonance (SPR) system induced by the electric field generates the effect of electrooptic-localized surface plasmon resonance (EO-LSPR). EO-LSPR is the promising method to increase dispersibility, generate plasmons, bind to biomolecular targets, modify the refractive index, and increase the SPR signal. Green synthesis of Fe₃O₄/Ag NPs has several advantages, including being environmentally friendly, cost-effective, and sustainable. This research successfully investigated the EO-LSPR properties of green-synthesized Fe₃O₄/Ag NPs with various Ag concentrations. Green synthesis of Fe₃O₄/Ag composites NPs was prepared utilizing Moringa oleifera by an aqueous solution method. The EO-LSPR phenomenon was investigated by applying various voltages in the Kretschmann configuration with a layer arrangement of a prism/Au thin film/NPs/air with a wavelength of 632.8 nm. Transmission electron microscope results show that the average size of Fe₃O₄/Ag particles is around 16.72 ± 7.30 nm. The scanning electron microscopy-energy dispersive x-ray results showed that Ag was distributed on the surface of Fe₃O₄. The addition of Ag concentration decreased the saturation magnetization while the coercivity field increased. The SPR angle of the prism/Au thin film/air layer structures is 44.66°. After depositing with Fe₃O₄/Ag with an Ag concentration of 60 millimolar, the LSPR angle shifted by 0.98°. Under an electric field, the LSPR angle shifted to 1.00°, 1.17°, and 1.22° of 2 volts, 4 volts, and 6 volts, respectively. The results show that applying the electric field induces the LSPR angle of Fe₃O₄/Ag NPs to shift to a larger angle. Applying an electric field causes a change in the material's refractive index. The greater the applied electric field, the more significant the LSPR angle shifts. The significant shifts in the LSPR angle due to the application of an electric field indicate that the EO-LSPR system using green-synthesized Fe₃O₄/Ag composites NPs could be a promising alternative to increase the performance of SPR biosensors in the future.

利用绿色合成的Fe ₃ O ₄ /Ag复合纳米粒子(NPs)在电场诱导的表面等离子体共振(SPR)系统上产生电光局域表面等离子体共振(EO-LSPR)效应。EO-LSPR 是提高分散性、产生等离子体、与生物分子靶标结合、改变折射率和增强 SPR 信号的有前途的方法。_{Fe 3} O ₄ /Ag NPs的绿色合成具有环境友好、成本效益和可持续等优点。本研究成功研究了不同Ag浓度的绿色合成Fe ₃ O _{4 /Ag NPs的EO-LSPR特性。}以辣木为原料，采用水溶液法绿色合成Fe ₃ O _{4 /Ag复合纳米粒子。}通过在波长为 632.8 nm 的棱镜/Au 薄膜/NPs/空气的层排列的 Kretschmann 配置中施加各种电压来研究 EO-LSPR 现象。透射电镜结果表明Fe ₃ O ₄ /Ag颗粒的平均尺寸约为16.72±7.30 nm。_{扫描电镜-能量色散X射线结果表明Ag分布在Fe 3} O ₄表面。Ag浓度的添加降低了饱和磁化强度，同时增加了矫顽力场。棱镜/Au薄膜/空气层结构的SPR角为44.66°。沉积Ag浓度为60毫摩尔的Fe ₃ O _{4 /Ag后，局域表面等离子体共振角偏移了0.98°。}在电场下，局域表面等离子体共振角分别偏移至1.00°、1.17°和1.22°，电压分别为2伏、4伏和6伏。结果表明，施加电场会导致Fe ₃ O ₄ /Ag NPs的局域表面等离子体共振角向更大的角度移动。施加电场会导致材料的折射率发生变化。施加的电场越大，局域表面等离子体共振角移越显着。由于施加电场而引起的局域表面等离子体共振角度的显着变化表明，使用绿色合成的 Fe ₃ O ₄ /Ag 复合纳米粒子的 EO-LSPR 系统可能是未来提高 SPR 生物传感器性能的有前景的替代方案。