Maebashi Institute of Technology, Gunma 371-0816, Japan.
Analyst. 2012 Aug 21;137(16):3781-6. doi: 10.1039/c2an35667h. Epub 2012 Jul 4.
To monitor protein-glycoprotein interactions on magnetic beads, the present study developed an electrochemical assay of the binding between concanavalin A (ConA) and ovalbumin (OVA). The system was a powerful model that could be used to evaluate cell junctions. ConA with an electroactive daunomycin was immobilized on 6 different sizes of magnetic beads (diameter: 1.0-8.9 μm) through a cross-linking agent. Six sizes of OVA-beads (diameter: 1.0-8.9 μm) were also prepared using a similar method. The binding was evaluated using an oxidation peak of ConA with daunomycin because ConA recognized OVA with α-mannose residues. When binding took place on the beads' surface, the peak current was decreased due to the electroactive moieties being covered with OVA. When ConA/daunomycin-OVA binding was evaluated, the change of the peak current obtained by the beads (diameter: 8.9 μm) modified with ConA and daunomycin was the greatest in the presence of OVA-modified beads (diameter: 2.5 μm). In contrast, particle agglomeration was observed for the smallest beads (diameter: 1.0 μm) with ConA/daunomycin and OVA. The results suggested that ConA-OVA binding depended on the size of beads. Thus, this method could be applied to measure protein-glycoprotein interactions on the cell surface.
为了监测磁珠上的蛋白质-糖蛋白相互作用，本研究开发了一种用于检测伴刀豆球蛋白 A（ConA）与卵清蛋白（OVA）之间结合的电化学分析方法。该系统是一种强大的模型，可用于评估细胞连接。通过交联剂将具有电化学活性的道诺霉素固定在 6 种不同大小的磁珠（直径：1.0-8.9μm）上。同样使用类似的方法制备了 6 种大小的 OVA 珠（直径：1.0-8.9μm）。由于 ConA 识别 OVA 上的α-甘露糖残基，因此可以通过 ConA 与道诺霉素的氧化峰来评估结合。当结合发生在珠的表面时，由于电活性部分被 OVA 覆盖，峰电流会减小。当评估 ConA/daunomycin-OVA 结合时，在存在 OVA 修饰珠（直径：2.5μm）的情况下，用 ConA 和 daunomycin 修饰的珠（直径：8.9μm）获得的峰电流变化最大。相比之下，对于具有 ConA/daunomycin 和 OVA 的最小珠（直径：1.0μm），观察到颗粒聚集。结果表明，ConA-OVA 结合取决于珠的大小。因此，该方法可用于测量细胞表面上的蛋白质-糖蛋白相互作用。
