Department of Bioengineering, Bilecik Şeyh Edebali University, 11230, Bilecik, Turkey.
Department of Chemistry, Kütahya Dumlupınar University, 43100, Kütahya, Turkey.
Talanta. 2022 Jan 15;237:122897. doi: 10.1016/j.talanta.2021.122897. Epub 2021 Oct 4.
The spectroscopic ellipsometry (SE), and attenuated internal reflection spectroscopic ellipsometry (TIRE) are promising methods in label-free biosensing applications. An ellipsometer running under surface plasmon resonance (SPR) conditions has unique advantages over other SPR-based methods in terms of sensitivity and real-time/label-free measurement capability. In this study, both SE and TIRE-based brevetoxin B (BTX) sensors were developed using two anti-BTX aptamers reported before. A new aptamer sequence was also derived from these two antiBTX aptamers using predictive modeling tools and an exclusion method. All three antiBTX aptamers' analytical performances were quite competitive in terms of both detecting range and detection limits. However, the selectivity of the previously reported aptamers against analogs of BTX was poor at low detection ranges, especially for okadaic acid. Furthermore, the selectivity of the derived aptamer was lower than its predecessors. The sensors were capable of detecting BTX in the range of 0.05 nM-1600 nM in the TIRE and 0.5 nM-2000 nM in the SE configuration. The detection limits of the sensors were 1.48 nM (1.32 ng/mL) and 0.80 nM (0.72 ng/mL) for SE and TIRE configurations, respectively. Both configurations have been used successfully to detect BTX standards spiked into real fish and shrimp samples.
光谱椭圆偏振术（SE）和衰减全内反射光谱椭圆偏振术（TIRE）是无标记生物传感应用中的有前途的方法。在表面等离子体共振（SPR）条件下运行的椭圆偏振仪在灵敏度和实时/无标记测量能力方面与其他基于 SPR 的方法相比具有独特的优势。在这项研究中，使用以前报道的两种抗 BTX 适体开发了基于 SE 和 TIRE 的 BTX 传感器。还使用预测建模工具和排除方法从这两种抗 BTX 适体中衍生出一种新的适体序列。所有三种抗 BTX 适体在检测范围和检测限方面都具有相当的竞争力。然而，以前报道的适体对 BTX 类似物的选择性在低检测范围内较差，尤其是对 okadaic 酸。此外，衍生适体的选择性低于其前身。传感器能够在 TIRE 中检测 0.05 nM-1600 nM 的 BTX，在 SE 配置中检测 0.5 nM-2000 nM 的 BTX。传感器的检测限分别为 SE 和 TIRE 配置中的 1.48 nM（1.32 ng/mL）和 0.80 nM（0.72 ng/mL）。两种配置都已成功用于检测添加到真实鱼类和虾类样品中的 BTX 标准品。
