PDF(Pubmed)
Abstract：
This study introduces an innovative electrochemical aptasensor designed for the highly sensitive and rapid detection of Legionella pneumophila serogroup 1 (L. pneumophila SG1), a particularly virulent strain associated with Legionellosis. Employing a rigorous selection process utilizing cell-based systematic evolution of ligands by exponential enrichment (cell-SELEX), we identified new high-affinity aptamers specifically tailored for L. pneumophila SG1. The selection process encompassed ten rounds of cell-SELEX cycles with live L. pneumophila, including multiple counter-selection steps against the closely related Legionella sub-species. The dissociation constant (Kd) of the highest affinity sequence to L. pneumophila SG1 was measured at 14.2 nM, representing a ten-fold increase in affinity in comparison with the previously reported aptamers. For the development of electrochemical aptasensor, a gold electrode was modified with the selected aptamer through the formation of self-assembled monolayers (SAMs). The newly developed aptasensor exhibited exceptional sensitivity, and specificity in detecting and differentiating various Legionella sp., with a detection limit of 5 colony forming units (CFU)/mL and an insignificant/negligible cross-reactivity with closely related sub-species. Furthermore, the aptasensor effectively detected L. pneumophila SG1 in spiked water samples, demonstrating an appreciable recovery percentage. This study shows the potential of our aptamer-based electrochemical biosensor as a promising approach for detecting L. pneumophila SG1 in diverse environments.
摘要：
这项研究介绍了一种创新的电化学传感器，旨在高灵敏度和快速检测嗜肺军团菌血清群1（L.嗜肺SG1)，一种与军团菌病有关的特别强毒株。采用严格的选择过程，利用基于细胞的指数富集配体系统进化（cell-SELEX），我们确定了专门为嗜肺乳杆菌SG1定制的新的高亲和力适体。选择过程包括10轮细胞-SELEX周期与活的嗜肺乳杆菌，包括针对密切相关的军团菌亚种的多个反选择步骤。对嗜肺乳杆菌SG1的最高亲和序列的解离常数(Kd)测量为14.2nM,与先前报道的适体相比，亲和力增加了十倍。为了开发电化学传感器，通过形成自组装单层(SAMs)用所选择的适体修饰金电极。新开发的aptasensor表现出卓越的灵敏度，以及检测和区分各种军团菌的特异性。,检测限为5个菌落形成单位（CFU）/mL，与密切相关的亚种的交叉反应性微不足道/可忽略不计。此外，aptasensor有效检测到加标水样中的嗜肺乳杆菌SG1，显示出可观的恢复百分比。这项研究显示了我们的基于适体的电化学生物传感器作为在不同环境中检测嗜肺乳杆菌SG1的有前途的方法的潜力。
