Department of Chemistry, School of Physical and Mathematical Science, University of Kerala, Thiruvananthapuram, Kerala, 695581, India.
Anal Methods. 2024 Oct 17;16(40):6899-6906. doi: 10.1039/d4ay01240b.
Fluorescence anisotropy (FA) is a versatile and efficient platform for developing biosensors that rely on the rate of rotations of fluorescence molecular entities in biochemical systems. However, by virtue of its intricate complexity, FA is a neglected and less explored area for developing biosensors. Herein, we experimented with the possibility of developing a fluorescence anisotropic probe to detect cardiac troponin I (cTnI), the gold standard biomarker for acute myocardial infarction, target-specific monoclonal antibody-conjugated gold nanoclusters. The successful detection of cTnI antigen in clinically relevant concentration with a low detection limit of 0.91 ng mL was achieved. The specific molecular interaction between the cTnI antigen and its monoclonal antibody tagged at the surface of gold nanoclusters has restricted the free rotation of gold nanoclusters and increased the FA value. This incremental increase in FA can be correlated to the concentration of cTnI antigen in the sample, thereby achieving the quantitative linear detection of cTnI.
荧光各向异性（FA）是开发生物传感器的一种通用且高效的平台，它依赖于生物化学系统中荧光分子实体的旋转速度。然而，由于其复杂的结构，FA 在开发生物传感器方面是一个被忽视且研究较少的领域。在此，我们尝试利用荧光各向异性探针来检测心肌肌钙蛋白 I（cTnI），这是急性心肌梗死的金标准生物标志物，目标特异性单克隆抗体偶联的金纳米簇。我们成功地以 0.91ng/mL 的低检测限检测到临床相关浓度的 cTnI 抗原。cTnI 抗原与其标记在金纳米簇表面的单克隆抗体之间的特异性分子相互作用限制了金纳米簇的自由旋转并增加了 FA 值。这种 FA 的增量增加可以与样品中 cTnI 抗原的浓度相关联，从而实现对 cTnI 的定量线性检测。
