School of Public Health, Southeast University, Nanjing 210009, China.
Anal Chim Acta. 2010 Jan 25;658(2):128-32. doi: 10.1016/j.aca.2009.11.007. Epub 2009 Nov 10.
A solid-state electrochemiluminescence sensing platform based on ferrocene-labeled structure-switching signaling aptamer (Fc-aptamer) for highly sensitive detection of small molecules is developed successfully using adenosine as a model analyte. Such special sensing platform included two main parts, an electrochemiluminescence (ECL) substrate and an ECL intensity switch. The ECL substrate was made by modifying the complex of Au nanoparticle and Ruthenium (II) tris-(bipyridine) (Ru(bpy)(3)(2+)-AuNPs) onto Au electrode. An anti-adenosine aptamer labeled by ferrocene acted as the ECL intensity switch. A short complementary ssDNA for the aptamer was applied to hybridizing with the aptamer, yielding a double-stranded complex of the aptamer and the ssDNA on the electrode surface. The introduction of adenosine triggered structure switching of the aptamer. As a result, the ssDNA was forced to dissociate from the sensing platform. Such structural change of the aptamer resulted in an obvious ECL intensity decrease due to the increased quenching effect of Fc to the ECL substrate. The analytic results were sensitive and specific.
基于二茂铁标记的结构切换信号适体（Fc-适体）的固态电化学发光传感平台，成功地用于以腺苷为模型分析物的小分子的高灵敏度检测。该特殊传感平台包括两个主要部分，电化学发光（ECL）基底和 ECL 强度开关。ECL 基底通过将金纳米粒子和钌（II）三（联吡啶）（Ru（bpy）（3）（2+）-AuNPs）复合物修饰到 Au 电极上制成。用二茂铁标记的抗腺苷适体作为 ECL 强度开关。适体的短互补 ssDNA 用于与适体杂交，在电极表面产生适体和 ssDNA 的双链复合物。腺苷的引入引发了适体的结构切换。结果，ssDNA 被迫从传感平台解离。由于 Fc 对 ECL 基底的淬灭效应增加，适体的这种结构变化导致 ECL 强度明显降低。分析结果具有灵敏性和特异性。
