In this paper, we report a D-type optical fiber biosensor for human immunoglobulin G (HIgG) detection based on surface plasmon resonance (SPR). The SPR phenomenon was both simulated by COMSOL and observed experimentally. To fabricate the sensor, the cladding of a multimode optical fiber (MMF) was polished using a grinding wheel to obtain a D-type cross-section. Next, a gold film was sputtered on the surface of the MMF. The optimal gold layer thickness and grinding depth were determined through simulations. As per the experimental results, the optimized sensor exhibited high refractive index (RI) sensitivity, which ranged from 1590.9 nm/RIU to 3513.3 nm/RIU for RI values of 1.343 to 1.373. Subsequently, Poly dimethyl diallyl ammonium chloride (PDDA) and Poly(sodium-p-styrenesulfonate) (PSS) were deposited four times in sequence to form polyelectrolyte self-assembled multilayers for the surface functionalization of the fiber. HIgG and goat anti-HIgG (GaHIgG) were chosen as the bioconjugate pair for evaluating the functionality of the fabricated biosensor, and the sensitivity to IgG was determined to be 91 nm/(mg/ml). The specificity of the biosensor was also verified through comparison tests performed using gelatin, horse IgG, and swine IgG. The obtained results confirmed the suitability of the biosensor for use in various biochemical applications.

在本文中，我们报告了一种基于表面等离振子共振（SPR）的用于人体免疫球蛋白G（HIgG）检测的D型光纤生物传感器。SPR现象通过COMSOL进行了模拟并通过实验观察到。为了制造传感器，使用砂轮对多模光纤（MMF）的包层进行抛光，以获得D型横截面。接着，将金膜溅射在MMF的表面上。通过模拟确定最佳的金层厚度和研磨深度。根据实验结果，优化后的传感器表现出高折射率（RI）灵敏度，对于RI值1.343至1.373，其灵敏度介于1590.9 nm / RIU至3513.3 nm / RIU之间。后来，聚二甲基二烯丙基氯化铵（PDDA）和聚对苯乙烯磺酸钠（PSS）依次沉积四次，以形成用于表面功能化的聚电解质自组装多层。选择HIgG和山羊抗HIgG（GaHIgG）作为生物偶联物对，以评估制成的生物传感器的功能，对IgG的敏感度确定为91 nm /（mg / ml）。通过使用明胶，马IgG和猪IgG进行的比较测试，也验证了生物传感器的特异性。所获得的结果证实了该生物传感器适用于各种生化应用。选择HIgG和山羊抗HIgG（GaHIgG）作为生物偶联物对，以评估制成的生物传感器的功能，对IgG的敏感度确定为91 nm /（mg / ml）。通过使用明胶，马IgG和猪IgG进行的比较测试，也验证了生物传感器的特异性。所获得的结果证实了该生物传感器适用于各种生化应用。选择HIgG和山羊抗HIgG（GaHIgG）作为生物偶联物对，以评估制成的生物传感器的功能，对IgG的敏感度确定为91 nm /（mg / ml）。通过使用明胶，马IgG和猪IgG进行的比较测试，也验证了生物传感器的特异性。所获得的结果证实了该生物传感器在各种生化应用中的适用性。