Optical fiber-based surface plasmon resonance (OF-SPR) sensors have demonstrated high versatility and performances over the last years, which propelled the technique to the heart of numerous and original biosensing concepts. In this work, we contribute to this effort and present our recent findings about the detection of breast cancer HER2 biomarkers through OF-SPR optrodes. 1 cm-long sections of 400 μm core-diameter optical fibers were covered with a sputtered gold film, yielding enhanced sensitivity to surface refractive index changes. Studying the impacts of the gold film thickness on the plasmonic spectral response, we improved the quality and reproducibility of the sensors. These achievements were correlated in two ways, using both the central wavelengths of the plasmon resonance and its influence on the bulk refractive index sensitivity. Our dataset was fed by additional biosensing experiments with a direct and indirect approach, relying on aptamers and antibodies specifically implemented in a sandwich layout. HER2 biomarkers were specifically detected at 0.6 μg/mL (5.16 nM) in label-free while the amplification with HER2-antibodies provided a nearly hundredfold signal magnification, reaching 9.3 ng/mL (77.4 pM). We believe that these results harbinger the way for their further use in biomedical samples.

在过去的几年中，基于光纤的表面等离振子共振（OF-SPR）传感器已经证明了其高通用性和高性能，这使该技术成为众多原始生物传感概念的核心。在这项工作中，我们为这项工作做出了贡献，并介绍了有关通过OF-SPR电极检测乳腺癌HER2生物标志物的最新发现。直径为400μm的1厘米长截面的光纤被溅射的金膜覆盖，从而提高了对表面折射率变化的敏感性。研究金膜厚度对等离子体光谱响应的影响，我们提高了传感器的质量和可重复性。使用等离振子共振的中心波长及其对体折射率灵敏度的影响，可以通过两种方式关联这些成就。我们的数据集通过直接和间接的其他生物传感实验得到补充，这些方法依赖于以三明治形式专门实现的适体和抗体。HER2生物标记物在无标记物中的特异性浓度为0.6μg/ mL（5.16 nM），而使用HER2抗体的扩增提供了近百倍的信号放大倍数，达到9.3 ng / mL（77.4 pM）。我们认为，这些结果为进一步将其用于生物医学样品开辟了道路。