We are presenting an electrochemical immunosensor for the determination of Galectin-3 (Gal-3), a biomarker of heart failure. A glassy carbon electrode (GCE) was modified with a film of a composite made from the N-doped graphene nanoribbons immobilized Fe-based-Metal-organic frameworks deposited with Au nanoparticles ([email protected]). Primary antibody against Gal-3 (Gal-3-Ab₁) was immobilized on the Au nanoparticles on the surface of the modified GCE which then was blocked with bovine serum albumin. Signal amplification is crucial for obtaining low detection limits in biosensors. Here, a relatively simple and ultrasensitive sandwich-type electrochemical immunosensor based on novel signal generation and amplification was developed for the determination of Gal-3. A kind of novel redox-active species, AuPt-Methylene blue (MB) (AuPt-MB) nanocomposites, was synthesized by a one-pot method for the first time. Wherein, MB as a kind of the electron transfer mediators in an amperometric biosensor is responsible for electron production and signal amplification. The rod-like AuPt-MB nanohybrids displayed uniform morphology and good electrochemical activity and can combine with the second antibodies against Gal-3 (Gal-3-Ab₂). And the AuPt-MB-Ab₂ coupled with the [email protected]₁ to form the sandwich type format that can greatly enhance the biosensor's sensitivity. Under optimal conditions, the designed immunosensor exhibited a linear concentration range from 100 fg mL⁻¹ to 50 ng mL⁻¹, with a low detection limit of 33.33 fg mL⁻¹ (S/N = 3) for Gal-3 in spiked serum. Additionally, the designed immunosensor showed acceptable selectivity, reproducibility and stability. The satisfactory results in analyzing human serum samples indicated potential application promising in monitoring biomarkers.

我们提出了一种电化学免疫传感器，用于测定心力衰竭的生物标记物Galectin-3（Gal-3）。玻碳电极（GCE）用复合材料薄膜改性，该复合材料薄膜由N掺杂的石墨烯纳米带固定化的，沉积有Au纳米粒子的Fe基金属有机骨架制成（[电子邮件保护]）。抗Gal-3（Gal-3-Ab _1的一抗将其固定在修饰的GCE表面上的Au纳米颗粒上，然后将其用牛血清白蛋白封闭。信号放大对于在生物传感器中获得低检测限至关重要。在这里，开发了一种基于新型信号产生和扩增的相对简单和超灵敏的夹心型电化学免疫传感器，用于测定Gal-3。首次通过单锅法合成了一种新型的氧化还原活性物质，AuPt-亚甲基蓝（MB）（AuPt-MB）纳米复合材料。其中，MB作为安培生物传感器中的一种电子传递介质，负责电子的产生和信号的放大。棒状AuPt-MB纳米杂化物表现出均匀的形态和良好的电化学活性，并且可以与针对Gal-3（Gal-3-Ab₂）。AuPt-MB-Ab ₂与[电子邮件保护] ₁结合形成三明治式格式，可以大大提高生物传感器的灵敏度。在最佳条件下，设计的免疫传感器的线性浓度范围为100 fg mL ^-1至50 ng mL ^-1，加标血清中Gal-3的检测限低至33.33 fg mL ^-1（S / N = 3） 。另外，设计的免疫传感器显示出可接受的选择性，再现性和稳定性。分析人血清样品的令人满意的结果表明在监测生物标志物方面的潜在应用前景广阔。