A strategy for amplifying the signal of surface plasmon resonance (SPR) biosensors is reported. Biotinylated phenylalanine (Biotin-Phe) monomers were rapidly self-assembled into nanoparticles in a mild environment. The self-assembled nanoparticles were then used as the carriers of streptavidin-antibody complexes by the streptavidin-biotin interaction. The signal was amplified because of the high molecular weight of the nanoparticle-streptavidin-antibody conjugate. With prostate-specific antigen as a model analyte, the target concentration as low as 1 pg mL−1 was readily measured. The results of the nanoparticle-enhanced SPR biosensor for analysis of serum samples are well consistent with those achieved by the enzyme-linked immunosorbent assays. This work is valuable for designing of various optical and electronic biosensors through the streptavidin-biotin interaction. Graphical abstract Graphical abstract

中文翻译：

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自组装生物素-苯丙氨酸纳米粒子用于表面等离子体共振生物传感器的信号放大

报道了一种放大表面等离子体共振 (SPR) 生物传感器信号的策略。生物素化苯丙氨酸 (Biotin-Phe) 单体在温和的环境中迅速自组装成纳米颗粒。然后通过链霉亲和素-生物素相互作用将自组装纳米颗粒用作链霉亲和素-抗体复合物的载体。由于纳米颗粒-链霉亲和素-抗体偶联物的高分子量，信号被放大。使用前列腺特异性抗原作为模型分析物，可轻松测量低至 1 pg mL-1 的目标浓度。用于分析血清样品的纳米颗粒增强型 SPR 生物传感器的结果与酶联免疫吸附测定所获得的结果非常一致。这项工作对于通过链霉亲和素-生物素相互作用设计各种光学和电子生物传感器很有价值。图形摘要图形摘要