Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa 464-8601, Japan.
Biomaterials. 2011 Feb;32(6):1455-64. doi: 10.1016/j.biomaterials.2010.10.057. Epub 2010 Nov 23.
To enhance the sensitivities and antigen-binding capacities of immunosensors, oriented immobilization of antibodies on the surface of the sensor chip is critical, but to date, this has not been adequately achieved. We describe a way of adsorbing immunoglobulin (Ig) proteins onto 32-nm bio-nanocapsules (BNCs) through IgG Fc-binding domains derived from Staphylococcus aureus protein A (ZZ-BNC). This arrangement permits approximately 60 molecules of mouse total IgG bind to ZZ-BNC and all the IgG Fv regions to be displayed outwardly for the effective binding of antigens. ZZ-BNCs adsorbed onto the gold surface of the sensor chip of the quartz crystal microbalance (QCM) could markedly enhance the sensitivity and antigen-binding capacity of the chip. On the sensor chip of surface plasmon resonance (SPR), antibodies on the ZZ-BNCs showed higher affinities to each antigen than those on protein A. The BNC-coated sensor chip is very stable, and should prove useful for various immunosensor applications due to oriented immobilization of antibodies.
为了提高免疫传感器的灵敏度和抗原结合能力，抗体在传感器芯片表面的定向固定至关重要，但迄今为止，这一点尚未得到充分实现。我们描述了一种通过金黄色葡萄球菌蛋白 A（ZZ-BNC）衍生的 IgG Fc 结合结构域将免疫球蛋白（Ig）蛋白吸附到 32nm 生物纳米胶囊（BNC）上的方法。这种排列方式允许大约 60 个鼠总 IgG 分子结合到 ZZ-BNC 上，并且所有 IgG Fv 区域都向外展示，以有效结合抗原。吸附在石英晶体微天平（QCM）传感器芯片金表面上的 ZZ-BNC 可以显著提高芯片的灵敏度和抗原结合能力。在表面等离子体共振（SPR）传感器芯片上，ZZ-BNC 上的抗体对每种抗原的亲和力均高于蛋白 A 上的抗体。由于抗体的定向固定，BNC 涂层的传感器芯片非常稳定，应该对各种免疫传感器应用有用。
