Kuramitz Hideki, Piruska Aigars, Halsall H Brian, Seliskar Carl J, Heineman William R
Department of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221-0172, USA.
Anal Chem. 2008 Dec 15;80(24):9642-8. doi: 10.1021/ac801289t.
A new binding assay for a protein and its ligand based on a spectroelectrochemical method was demonstrated using avidin-biotin and 17beta-estradiol-antiestradiol antibody. The sensor consists of a selective film coated on an optically transparent electrode (OTE) consisting of indium tin oxide (ITO). Attenuated total reflection (ATR) was used for optical detection. The binding event of the ligand to the protein was detected using the ligand labeled with the electroactive dye Nile blue (NB). The spectroelectrochemical behaviors of NB and the labeled ligand were investigated using various ion-exchange films, such as perfluorosulfonated ionomer (Nafion), Nafion-silica, poly(acrylic acid) (PAA)-silica, poly(styrenesulfonic acid) (PSSA)-silica, and heparin-silica films, which were spin-coated on the ITO electrode. The optical signal was monitored to follow the accumulation of labeled ligand in the film and its electrochemical modulation. The signal from the labeled ligand possesses three modes of selectivity based on charge-selective partitioning, the chosen electrolysis potential, and the particular wavelength for measuring absorbance. The interaction between the labeled ligand and its protein was observed by the decrease in the changes of optical response of the labeled ligand, indicating the specific binding of labeled ligand to the protein.
利用抗生物素蛋白-生物素和17β-雌二醇-抗雌二醇抗体，基于光谱电化学方法建立了一种用于蛋白质及其配体的新型结合测定法。该传感器由涂覆在由氧化铟锡（ITO）构成的光学透明电极（OTE）上的选择性薄膜组成。采用衰减全反射（ATR）进行光学检测。使用标记有电活性染料尼罗蓝（NB）的配体检测配体与蛋白质的结合事件。使用各种离子交换膜，如全氟磺酸离子聚合物（Nafion）、Nafion-二氧化硅、聚丙烯酸（PAA）-二氧化硅、聚苯乙烯磺酸（PSSA）-二氧化硅和肝素-二氧化硅膜，研究了NB和标记配体的光谱电化学行为，这些膜通过旋涂在ITO电极上。监测光信号以跟踪标记配体在膜中的积累及其电化学调制。来自标记配体的信号基于电荷选择性分配、选定的电解电位和用于测量吸光度的特定波长具有三种选择性模式。通过标记配体光响应变化的降低观察到标记配体与其蛋白质之间的相互作用，表明标记配体与蛋白质的特异性结合。
